Location: Chay, 1997 @ 4b95873501e3 / chay_1997.cellml

Author:
Hanne <Hanne@hanne-nielsens-macbook.local>
Date:
2010-05-11 13:53:27+12:00
Desc:
Integrated clickalbe SVG to session file, aded images in ai and svg format
Permanent Source URI:
https://models.cellml.org/workspace/chay_1997/rawfile/4b95873501e328e3160c51597720ef4eb45391e4/chay_1997.cellml

<?xml version="1.0"?>
<!--
This CellML file was generated on 29/10/2007 at 13:15:07 using:

COR (0.9.31.801)
Copyright 2002-2007 Dr Alan Garny
http://COR.physiol.ox.ac.uk/ - COR@physiol.ox.ac.uk

CellML 1.0 was used to generate this cellular model
http://www.CellML.org/
--><model xmlns="http://www.cellml.org/cellml/1.0#" xmlns:cmeta="http://www.cellml.org/metadata/1.0#" xml:base="" cmeta:id="chay_1997" name="chay_1997">
   
<documentation xmlns="http://cellml.org/tmp-documentation">
<article>
  <articleinfo>
  <title>Extracellular And Intracellular Calcium Effects On Pancreatic Beta-Cells</title>
  <author>
    <firstname>Catherine</firstname>
          <surname>Lloyd</surname>
    <affiliation>
      <shortaffil>Oxford University</shortaffil>
    </affiliation>
  </author>
</articleinfo>
  <section id="sec_status">
    <title>Model Status</title>
    <para>
           This model is able to reproduce the figures presented in the Chay 1997 paper and this version has a PCEnv session file associated with it. The value for the variable 'Ca_o' in the component 'calcium_current' can be altered to 0, 2.5, 5 or 7.5 mM to reproduce figures 5 a,b,c,d, respectively.
          </para>
<para>
ValidateCellML verfies this model as valid CellML with fully consistent units.
</para>
  </section>
  <sect1 id="sec_structure">
<title>Model Structure</title>

<para>
When exposed to a threshold concentration of glucose, pancreatic beta-cells exhibit a complicated pattern of electrical activity.  Bursts of action potential spikes (the "active" phase) are observed, separated by a "silent" phase of membrane repolarisation.  At even higher glucose concentrations, continuous action potentials are seen.  This electrical activity is influenced by the extracellular calcium concentration ([Ca<superscript>2+</superscript>]<subscript>o</subscript>).  Specifically, in a mouse pancreatic beta-cell in a medium containing a moderate amount of glucose, an increase in [Ca<superscript>2+</superscript>]<subscript>o</subscript> lowers the repolarisation potential, raises the plateau potential and shortens the spike and plateau durations.  The mechanisms underlying these affects are not well understood.
</para>

<para>  
In her 1997 paper, Teresa Chay elucidates the role of extracellular calcium concentration in influencing electrical activity, intracellular calcium concentration, and the luminal calcium concentration in the intracellular calcium store of pancreatic beta-cells.  She studies the extracellular calcium effect using a mathematical model which includes seven currents across the plasma membrane and two calcium fluxes across the membrane of the endoplasmic reticulum (ER) (see <xref linkend="fig_cell_diagram"/> below).
</para>

<para>
The complete original paper reference is cited below:
</para>

<para>
Effects of extracellular Calcium on Electrical Bursting and Intracellular  and Luminal Calcium Oscillations in Insulin Secreting Pancreatic Beta-Cells, Teresa Ree Chay, 1997, 
            <emphasis>Biophysical Journal</emphasis>
          , 73, 1673-1688.  <ulink url="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&amp;db=PubMed&amp;list_uids=9284334&amp;dopt=Abstract">PubMed ID: 9284334</ulink>  
</para>

<para>
The raw CellML description of the model can be downloaded in various formats as described in <xref linkend="sec_download_this_model"/>
</para>

<informalfigure float="0" id="fig_cell_diagram">
<mediaobject>
  <imageobject>
    <objectinfo>
      <title>diagram of the mitochondrial Ca2+ handling model</title>
    </objectinfo>
    <imagedata fileref="chay_1997.png"/>
  </imageobject>
</mediaobject>
<caption>A schematic representation of the current and fluxes captured by the Chay 1997 pancreatic beta-cell model.  This diagram shows the plasma membrane currents associated with burst and spike oscillations: the fast current, I<subscript>fast</subscript>; the calcium current, I <subscript>Ca<superscript>2+</superscript>
            </subscript>; the cationic nonselective inward current, I<subscript>NS</subscript>; the delayed-rectifying K<superscript>+</superscript> current, I<subscript>K(dr)</subscript>, the calcium-sensitive K<superscript>+</superscript> current, I<subscript>K(Ca)</subscript>; the ATP-sensitive K<superscript>+</superscript> current, I<subscript>K(ATP)</subscript>; and the Na<superscript>+</superscript> leak current, I<subscript>Na(L)</subscript>.  The ER intracellular Ca<superscript>2+</superscript> store is also shown with its associated transmembrane calcium fluxes: calcium release, J<subscript>rel</subscript>; and calcium uptake by the Ca<superscript>2+</superscript>-ATPase, J<subscript>pump</subscript>.</caption>
</informalfigure>

</sect1>
</article>
</documentation>
   <units name="per_second">
      <unit exponent="-1" units="second"/>
   </units>
   <units name="millivolt">
      <unit prefix="milli" units="volt"/>
   </units>
   <units name="per_millivolt">
      <unit exponent="-1" units="millivolt"/>
   </units>
   <units name="micromolar">
      <unit prefix="micro" units="mole"/>
      <unit exponent="-1" units="litre"/>
   </units>
   <units name="microS_per_cm2">
      <unit prefix="micro" units="siemens"/>
      <unit exponent="-2" prefix="centi" units="metre"/>
   </units>
   <units name="microF_per_cm2">
      <unit prefix="micro" units="farad"/>
      <unit exponent="-2" prefix="centi" units="metre"/>
   </units>
   <units name="nanoA_per_cm2">
      <unit prefix="nano" units="ampere"/>
      <unit exponent="-2" prefix="centi" units="metre"/>
   </units>
   <units name="nanoA_per_micromolar_per_cm2">
      <unit prefix="nano" units="ampere"/>
      <unit exponent="-1" units="micromolar"/>
      <unit exponent="-2" prefix="centi" units="metre"/>
   </units>
   <units name="micromolar_cm2_per_nanoA_per_second">
      <unit exponent="-1" prefix="nano" units="ampere"/>
      <unit units="micromolar"/>
      <unit exponent="2" prefix="centi" units="metre"/>
      <unit exponent="-1" units="second"/>
   </units>
   <units name="millijoule_per_mole_kelvin">
      <unit prefix="milli" units="joule"/>
      <unit exponent="-1" units="mole"/>
      <unit exponent="-1" units="kelvin"/>
   </units>
   <units name="coulomb_per_mole">
      <unit units="coulomb"/>
      <unit exponent="-1" units="mole"/>
   </units>
   <component name="environment">
      <variable cmeta:id="environment_time" name="time" public_interface="out" units="second"/>
   </component>
   <component name="membrane">
      <variable cmeta:id="membrane_V" initial_value="-38.34146" name="V" public_interface="out" units="millivolt"/>
      <variable initial_value="8314" name="R" public_interface="out" units="millijoule_per_mole_kelvin"/>
      <variable initial_value="310" name="T" public_interface="out" units="kelvin"/>
      <variable initial_value="96485" name="F" public_interface="out" units="coulomb_per_mole"/>
      <variable initial_value="1" name="Cm" units="microF_per_cm2"/>
      <variable name="time" public_interface="in" units="second"/>
      <variable name="i_K_dr" public_interface="in" units="nanoA_per_cm2"/>
      <variable name="i_K_Ca" public_interface="in" units="nanoA_per_cm2"/>
      <variable name="i_K_ATP" public_interface="in" units="nanoA_per_cm2"/>
      <variable name="i_fast" public_interface="in" units="nanoA_per_cm2"/>
      <variable name="i_Ca" public_interface="in" units="nanoA_per_cm2"/>
      <variable name="i_NS" public_interface="in" units="nanoA_per_cm2"/>
      <variable name="i_NaL" public_interface="in" units="nanoA_per_cm2"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <apply>
               <diff/>
               <bvar>
                  <ci>time</ci>
               </bvar>
               <ci>V</ci>
            </apply>
            <apply>
               <divide/>
               <apply>
                  <minus/>
                  <apply>
                     <plus/>
                     <ci>i_K_dr</ci>
                     <ci>i_K_Ca</ci>
                     <ci>i_K_ATP</ci>
                     <ci>i_fast</ci>
                     <ci>i_Ca</ci>
                     <ci>i_NS</ci>
                     <ci>i_NaL</ci>
                  </apply>
               </apply>
               <ci>Cm</ci>
            </apply>
         </apply>
      </math>
   </component>
   <component name="fast_current">
      <variable cmeta:id="fast_current_i_fast" name="i_fast" public_interface="out" units="nanoA_per_cm2"/>
      <variable initial_value="600" name="g_fast" units="microS_per_cm2"/>
      <variable initial_value="80" name="V_fast" units="millivolt"/>
      <variable name="time" private_interface="out" public_interface="in" units="second"/>
      <variable name="V" private_interface="out" public_interface="in" units="millivolt"/>
      <variable name="m_infinity" private_interface="in" units="dimensionless"/>
      <variable name="h" private_interface="in" units="dimensionless"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <ci>i_fast</ci>
            <apply>
               <times/>
               <ci>g_fast</ci>
               <apply>
                  <power/>
                  <ci>m_infinity</ci>
                  <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">3</cn>
               </apply>
               <ci>h</ci>
               <apply>
                  <minus/>
                  <ci>V</ci>
                  <ci>V_fast</ci>
               </apply>
            </apply>
         </apply>
      </math>
   </component>
   <component name="fast_current_m_gate">
      <variable name="m_infinity" public_interface="out" units="dimensionless"/>
      <variable initial_value="-25" name="Vm" units="millivolt"/>
      <variable initial_value="9" name="Sm" units="millivolt"/>
      <variable name="V" public_interface="in" units="millivolt"/>
      <variable name="time" public_interface="in" units="second"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <ci>m_infinity</ci>
            <apply>
               <divide/>
               <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">1</cn>
               <apply>
                  <plus/>
                  <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">1</cn>
                  <apply>
                     <exp/>
                     <apply>
                        <divide/>
                        <apply>
                           <minus/>
                           <ci>Vm</ci>
                           <ci>V</ci>
                        </apply>
                        <ci>Sm</ci>
                     </apply>
                  </apply>
               </apply>
            </apply>
         </apply>
      </math>
   </component>
   <component name="fast_current_h_gate">
      <variable initial_value="0.214723" name="h" public_interface="out" units="dimensionless"/>
      <variable initial_value="12.5" name="lamda_h" units="per_second"/>
      <variable name="tau_h" units="second"/>
      <variable name="h_infinity" units="dimensionless"/>
      <variable initial_value="-48" name="Vh" units="millivolt"/>
      <variable initial_value="-7" name="Sh" units="millivolt"/>
      <variable name="V" public_interface="in" units="millivolt"/>
      <variable name="time" public_interface="in" units="second"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <apply>
               <diff/>
               <bvar>
                  <ci>time</ci>
               </bvar>
               <ci>h</ci>
            </apply>
            <apply>
               <divide/>
               <apply>
                  <minus/>
                  <ci>h_infinity</ci>
                  <ci>h</ci>
               </apply>
               <ci>tau_h</ci>
            </apply>
         </apply>
         <apply>
            <eq/>
            <ci>h_infinity</ci>
            <apply>
               <divide/>
               <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">1</cn>
               <apply>
                  <plus/>
                  <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">1</cn>
                  <apply>
                     <exp/>
                     <apply>
                        <divide/>
                        <apply>
                           <minus/>
                           <ci>Vh</ci>
                           <ci>V</ci>
                        </apply>
                        <ci>Sh</ci>
                     </apply>
                  </apply>
               </apply>
            </apply>
         </apply>
         <apply>
            <eq/>
            <ci>tau_h</ci>
            <apply>
               <divide/>
               <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">1</cn>
               <apply>
                  <times/>
                  <ci>lamda_h</ci>
                  <apply>
                     <plus/>
                     <apply>
                        <exp/>
                        <apply>
                           <divide/>
                           <apply>
                              <minus/>
                              <ci>Vh</ci>
                              <ci>V</ci>
                           </apply>
                           <apply>
                              <times/>
                              <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">2</cn>
                              <ci>Sh</ci>
                           </apply>
                        </apply>
                     </apply>
                     <apply>
                        <exp/>
                        <apply>
                           <divide/>
                           <apply>
                              <minus/>
                              <ci>V</ci>
                              <ci>Vh</ci>
                           </apply>
                           <apply>
                              <times/>
                              <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">2</cn>
                              <ci>Sh</ci>
                           </apply>
                        </apply>
                     </apply>
                  </apply>
               </apply>
            </apply>
         </apply>
      </math>
   </component>
   <component name="calcium_current">
      <variable cmeta:id="calcium_current_i_Ca" name="i_Ca" public_interface="out" units="nanoA_per_cm2"/>
      <variable initial_value="1" name="K_Ca" private_interface="out" public_interface="out" units="micromolar"/>
      <variable initial_value="2" name="P_Ca" units="nanoA_per_micromolar_per_cm2"/>
      <variable initial_value="2500" name="Ca_o" units="micromolar"/>
      <variable name="R" public_interface="in" units="millijoule_per_mole_kelvin"/>
      <variable name="F" public_interface="in" units="coulomb_per_mole"/>
      <variable name="T" public_interface="in" units="kelvin"/>
      <variable name="time" private_interface="out" public_interface="in" units="second"/>
      <variable name="V" private_interface="out" public_interface="in" units="millivolt"/>
      <variable name="Ca_i" private_interface="out" public_interface="in" units="micromolar"/>
      <variable name="f_infinity" private_interface="in" units="dimensionless"/>
      <variable name="d" private_interface="in" units="dimensionless"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <ci>i_Ca</ci>
            <apply>
               <divide/>
               <apply>
                  <times/>
                  <apply>
                     <divide/>
                     <apply>
                        <times/>
                        <ci>P_Ca</ci>
                        <ci>d</ci>
                        <ci>f_infinity</ci>
                        <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">2</cn>
                        <ci>F</ci>
                        <ci>V</ci>
                     </apply>
                     <apply>
                        <times/>
                        <ci>R</ci>
                        <ci>T</ci>
                     </apply>
                  </apply>
                  <apply>
                     <minus/>
                     <ci>Ca_o</ci>
                     <apply>
                        <times/>
                        <ci>Ca_i</ci>
                        <apply>
                           <exp/>
                           <apply>
                              <divide/>
                              <apply>
                                 <times/>
                                 <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">2</cn>
                                 <ci>F</ci>
                                 <ci>V</ci>
                              </apply>
                              <apply>
                                 <times/>
                                 <ci>R</ci>
                                 <ci>T</ci>
                              </apply>
                           </apply>
                        </apply>
                     </apply>
                  </apply>
               </apply>
               <apply>
                  <minus/>
                  <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">1</cn>
                  <apply>
                     <exp/>
                     <apply>
                        <divide/>
                        <apply>
                           <times/>
                           <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">2</cn>
                           <ci>F</ci>
                           <ci>V</ci>
                        </apply>
                        <apply>
                           <times/>
                           <ci>R</ci>
                           <ci>T</ci>
                        </apply>
                     </apply>
                  </apply>
               </apply>
            </apply>
         </apply>
      </math>
   </component>
   <component name="calcium_current_d_gate">
      <variable initial_value="0.0031711238" name="d" public_interface="out" units="dimensionless"/>
      <variable initial_value="2.5" name="lamda_d" units="per_second"/>
      <variable name="tau_d" units="second"/>
      <variable name="d_infinity" units="dimensionless"/>
      <variable initial_value="-10" name="Vd" units="millivolt"/>
      <variable initial_value="5" name="Sd" units="millivolt"/>
      <variable name="V" public_interface="in" units="millivolt"/>
      <variable name="time" public_interface="in" units="second"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <apply>
               <diff/>
               <bvar>
                  <ci>time</ci>
               </bvar>
               <ci>d</ci>
            </apply>
            <apply>
               <divide/>
               <apply>
                  <minus/>
                  <ci>d_infinity</ci>
                  <ci>d</ci>
               </apply>
               <ci>tau_d</ci>
            </apply>
         </apply>
         <apply>
            <eq/>
            <ci>d_infinity</ci>
            <apply>
               <divide/>
               <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">1</cn>
               <apply>
                  <plus/>
                  <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">1</cn>
                  <apply>
                     <exp/>
                     <apply>
                        <divide/>
                        <apply>
                           <minus/>
                           <ci>Vd</ci>
                           <ci>V</ci>
                        </apply>
                        <ci>Sd</ci>
                     </apply>
                  </apply>
               </apply>
            </apply>
         </apply>
         <apply>
            <eq/>
            <ci>tau_d</ci>
            <apply>
               <divide/>
               <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">1</cn>
               <apply>
                  <times/>
                  <ci>lamda_d</ci>
                  <apply>
                     <plus/>
                     <apply>
                        <exp/>
                        <apply>
                           <divide/>
                           <apply>
                              <minus/>
                              <ci>Vd</ci>
                              <ci>V</ci>
                           </apply>
                           <apply>
                              <times/>
                              <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">2</cn>
                              <ci>Sd</ci>
                           </apply>
                        </apply>
                     </apply>
                     <apply>
                        <exp/>
                        <apply>
                           <divide/>
                           <apply>
                              <minus/>
                              <ci>V</ci>
                              <ci>Vd</ci>
                           </apply>
                           <apply>
                              <times/>
                              <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">2</cn>
                              <ci>Sd</ci>
                           </apply>
                        </apply>
                     </apply>
                  </apply>
               </apply>
            </apply>
         </apply>
      </math>
   </component>
   <component name="calcium_current_f_gate">
      <variable name="f_infinity" public_interface="out" units="dimensionless"/>
      <variable name="K_Ca" public_interface="in" units="micromolar"/>
      <variable name="Ca_i" public_interface="in" units="micromolar"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <ci>f_infinity</ci>
            <apply>
               <divide/>
               <ci>K_Ca</ci>
               <apply>
                  <plus/>
                  <ci>K_Ca</ci>
                  <ci>Ca_i</ci>
               </apply>
            </apply>
         </apply>
      </math>
   </component>
   <component name="cationic_nonselective_inward_current">
      <variable cmeta:id="cationic_nonselective_inward_current_i_NS" name="i_NS" public_interface="out" units="nanoA_per_cm2"/>
      <variable initial_value="5" name="g_NS" units="microS_per_cm2"/>
      <variable initial_value="50" name="K_NS" units="micromolar"/>
      <variable initial_value="-20" name="VNS" units="millivolt"/>
      <variable name="Ca_lum" public_interface="in" units="micromolar"/>
      <variable name="V" public_interface="in" units="millivolt"/>
      <variable name="time" public_interface="in" units="second"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <ci>i_NS</ci>
            <apply>
               <times/>
               <apply>
                  <divide/>
                  <apply>
                     <times/>
                     <ci>g_NS</ci>
                     <apply>
                        <power/>
                        <ci>K_NS</ci>
                        <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">2</cn>
                     </apply>
                  </apply>
                  <apply>
                     <plus/>
                     <apply>
                        <power/>
                        <ci>K_NS</ci>
                        <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">2</cn>
                     </apply>
                     <apply>
                        <power/>
                        <ci>Ca_lum</ci>
                        <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">2</cn>
                     </apply>
                  </apply>
               </apply>
               <apply>
                  <minus/>
                  <apply>
                     <divide/>
                     <apply>
                        <minus/>
                        <ci>V</ci>
                        <ci>VNS</ci>
                     </apply>
                     <apply>
                        <minus/>
                        <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">1</cn>
                        <apply>
                           <exp/>
                           <apply>
                              <times/>
                              <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="per_millivolt">0.1</cn>
                              <apply>
                                 <minus/>
                                 <ci>VNS</ci>
                                 <ci>V</ci>
                              </apply>
                           </apply>
                        </apply>
                     </apply>
                  </apply>
                  <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="millivolt">10</cn>
               </apply>
            </apply>
         </apply>
      </math>
   </component>
   <component name="delayed_rectifier_K_channel_current">
      <variable cmeta:id="delayed_rectifier_K_channel_current_i_K_dr" name="i_K_dr" public_interface="out" units="nanoA_per_cm2"/>
      <variable initial_value="-75" name="V_K" public_interface="out" units="millivolt"/>
      <variable initial_value="600" name="g_K_dr" units="microS_per_cm2"/>
      <variable name="time" private_interface="out" public_interface="in" units="second"/>
      <variable name="V" private_interface="out" public_interface="in" units="millivolt"/>
      <variable name="n" private_interface="in" units="dimensionless"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <ci>i_K_dr</ci>
            <apply>
               <times/>
               <ci>g_K_dr</ci>
               <apply>
                  <power/>
                  <ci>n</ci>
                  <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">4</cn>
               </apply>
               <apply>
                  <minus/>
                  <ci>V</ci>
                  <ci>V_K</ci>
               </apply>
            </apply>
         </apply>
      </math>
   </component>
   <component name="delayed_rectifier_K_channel_current_n_gate">
      <variable initial_value="0.1836403" name="n" public_interface="out" units="dimensionless"/>
      <variable initial_value="12.5" name="lamda_n" units="per_second"/>
      <variable initial_value="-18" name="Vn" units="millivolt"/>
      <variable initial_value="14" name="Sn" units="millivolt"/>
      <variable name="n_infinity" units="dimensionless"/>
      <variable name="tau_n" units="second"/>
      <variable name="V" public_interface="in" units="millivolt"/>
      <variable name="time" public_interface="in" units="second"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <apply>
               <diff/>
               <bvar>
                  <ci>time</ci>
               </bvar>
               <ci>n</ci>
            </apply>
            <apply>
               <divide/>
               <apply>
                  <minus/>
                  <ci>n_infinity</ci>
                  <ci>n</ci>
               </apply>
               <ci>tau_n</ci>
            </apply>
         </apply>
         <apply>
            <eq/>
            <ci>n_infinity</ci>
            <apply>
               <divide/>
               <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">1</cn>
               <apply>
                  <plus/>
                  <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">1</cn>
                  <apply>
                     <exp/>
                     <apply>
                        <divide/>
                        <apply>
                           <minus/>
                           <ci>Vn</ci>
                           <ci>V</ci>
                        </apply>
                        <ci>Sn</ci>
                     </apply>
                  </apply>
               </apply>
            </apply>
         </apply>
         <apply>
            <eq/>
            <ci>tau_n</ci>
            <apply>
               <divide/>
               <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">1</cn>
               <apply>
                  <times/>
                  <ci>lamda_n</ci>
                  <apply>
                     <plus/>
                     <apply>
                        <exp/>
                        <apply>
                           <divide/>
                           <apply>
                              <minus/>
                              <ci>Vn</ci>
                              <ci>V</ci>
                           </apply>
                           <apply>
                              <times/>
                              <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">2</cn>
                              <ci>Sn</ci>
                           </apply>
                        </apply>
                     </apply>
                     <apply>
                        <exp/>
                        <apply>
                           <divide/>
                           <apply>
                              <minus/>
                              <ci>V</ci>
                              <ci>Vn</ci>
                           </apply>
                           <apply>
                              <times/>
                              <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">2</cn>
                              <ci>Sn</ci>
                           </apply>
                        </apply>
                     </apply>
                  </apply>
               </apply>
            </apply>
         </apply>
      </math>
   </component>
   <component name="Ca_sensitive_K_current">
      <variable cmeta:id="Ca_sensitive_K_current_i_K_Ca" name="i_K_Ca" public_interface="out" units="nanoA_per_cm2"/>
      <variable initial_value="5" name="g_K_Ca" units="microS_per_cm2"/>
      <variable name="K_Ca" public_interface="in" units="micromolar"/>
      <variable name="time" public_interface="in" units="second"/>
      <variable name="V" public_interface="in" units="millivolt"/>
      <variable name="V_K" public_interface="in" units="millivolt"/>
      <variable name="Ca_i" public_interface="in" units="micromolar"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <ci>i_K_Ca</ci>
            <apply>
               <times/>
               <apply>
                  <divide/>
                  <apply>
                     <times/>
                     <ci>g_K_Ca</ci>
                     <apply>
                        <power/>
                        <ci>Ca_i</ci>
                        <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">3</cn>
                     </apply>
                  </apply>
                  <apply>
                     <plus/>
                     <apply>
                        <power/>
                        <ci>K_Ca</ci>
                        <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">3</cn>
                     </apply>
                     <apply>
                        <power/>
                        <ci>Ca_i</ci>
                        <cn xmlns:cellml="http://www.cellml.org/cellml/1.0#" cellml:units="dimensionless">3</cn>
                     </apply>
                  </apply>
               </apply>
               <apply>
                  <minus/>
                  <ci>V</ci>
                  <ci>V_K</ci>
               </apply>
            </apply>
         </apply>
      </math>
   </component>
   <component name="ATP_sensitive_K_current">
      <variable cmeta:id="ATP_sensitive_K_current_i_K_ATP" name="i_K_ATP" public_interface="out" units="nanoA_per_cm2"/>
      <variable initial_value="2" name="g_K_ATP" units="microS_per_cm2"/>
      <variable name="time" public_interface="in" units="second"/>
      <variable name="V" public_interface="in" units="millivolt"/>
      <variable name="V_K" public_interface="in" units="millivolt"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <ci>i_K_ATP</ci>
            <apply>
               <times/>
               <ci>g_K_ATP</ci>
               <apply>
                  <minus/>
                  <ci>V</ci>
                  <ci>V_K</ci>
               </apply>
            </apply>
         </apply>
      </math>
   </component>
   <component name="Na_leak_current">
      <variable cmeta:id="Na_leak_current_i_NaL" name="i_NaL" public_interface="out" units="nanoA_per_cm2"/>
      <variable initial_value="0.3" name="g_NaL" units="microS_per_cm2"/>
      <variable initial_value="80" name="V_Na" units="millivolt"/>
      <variable name="time" public_interface="in" units="second"/>
      <variable name="V" public_interface="in" units="millivolt"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <ci>i_NaL</ci>
            <apply>
               <times/>
               <ci>g_NaL</ci>
               <apply>
                  <minus/>
                  <ci>V</ci>
                  <ci>V_Na</ci>
               </apply>
            </apply>
         </apply>
      </math>
   </component>
   <component name="cytosolic_calcium">
      <variable cmeta:id="cytosolic_calcium_Ca_i" initial_value="0.6959466" name="Ca_i" public_interface="out" units="micromolar"/>
      <variable cmeta:id="cytosolic_calcium_Ca_lum" initial_value="102.686" name="Ca_lum" public_interface="out" units="micromolar"/>
      <variable initial_value="0.2" name="k_rel" units="per_second"/>
      <variable initial_value="7" name="k_Ca" units="per_second"/>
      <variable initial_value="30" name="k_pump" units="per_second"/>
      <variable initial_value="0.2" name="omega" units="micromolar_cm2_per_nanoA_per_second"/>
      <variable name="i_Ca" public_interface="in" units="nanoA_per_cm2"/>
      <variable name="time" public_interface="in" units="second"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <apply>
               <diff/>
               <bvar>
                  <ci>time</ci>
               </bvar>
               <ci>Ca_i</ci>
            </apply>
            <apply>
               <minus/>
               <apply>
                  <times/>
                  <ci>k_rel</ci>
                  <apply>
                     <minus/>
                     <ci>Ca_lum</ci>
                     <ci>Ca_i</ci>
                  </apply>
               </apply>
               <apply>
                  <plus/>
                  <apply>
                     <times/>
                     <ci>omega</ci>
                     <ci>i_Ca</ci>
                  </apply>
                  <apply>
                     <times/>
                     <ci>k_Ca</ci>
                     <ci>Ca_i</ci>
                  </apply>
                  <apply>
                     <times/>
                     <ci>k_pump</ci>
                     <ci>Ca_i</ci>
                  </apply>
               </apply>
            </apply>
         </apply>
         <apply>
            <eq/>
            <apply>
               <diff/>
               <bvar>
                  <ci>time</ci>
               </bvar>
               <ci>Ca_lum</ci>
            </apply>
            <apply>
               <plus/>
               <apply>
                  <times/>
                  <apply>
                     <minus/>
                     <ci>k_rel</ci>
                  </apply>
                  <apply>
                     <minus/>
                     <ci>Ca_lum</ci>
                     <ci>Ca_i</ci>
                  </apply>
               </apply>
               <apply>
                  <times/>
                  <ci>k_pump</ci>
                  <ci>Ca_i</ci>
               </apply>
            </apply>
         </apply>
      </math>
   </component>
   <group>
      <relationship_ref relationship="containment"/>
      <component_ref component="membrane">
         <component_ref component="fast_current">
            <component_ref component="fast_current_m_gate"/>
            <component_ref component="fast_current_h_gate"/>
         </component_ref>
         <component_ref component="calcium_current">
            <component_ref component="calcium_current_d_gate"/>
            <component_ref component="calcium_current_f_gate"/>
         </component_ref>
         <component_ref component="cationic_nonselective_inward_current"/>
         <component_ref component="delayed_rectifier_K_channel_current">
            <component_ref component="delayed_rectifier_K_channel_current_n_gate"/>
         </component_ref>
         <component_ref component="Ca_sensitive_K_current"/>
         <component_ref component="ATP_sensitive_K_current"/>
         <component_ref component="Na_leak_current"/>
         <component_ref component="cytosolic_calcium"/>
      </component_ref>
   </group>
   <group>
      <relationship_ref relationship="encapsulation"/>
      <component_ref component="fast_current">
         <component_ref component="fast_current_m_gate"/>
         <component_ref component="fast_current_h_gate"/>
      </component_ref>
      <component_ref component="calcium_current">
         <component_ref component="calcium_current_d_gate"/>
         <component_ref component="calcium_current_f_gate"/>
      </component_ref>
      <component_ref component="delayed_rectifier_K_channel_current">
         <component_ref component="delayed_rectifier_K_channel_current_n_gate"/>
      </component_ref>
   </group>
   <connection>
      <map_components component_1="membrane" component_2="environment"/>
      <map_variables variable_1="time" variable_2="time"/>
   </connection>
   <connection>
      <map_components component_1="fast_current" component_2="environment"/>
      <map_variables variable_1="time" variable_2="time"/>
   </connection>
   <connection>
      <map_components component_1="calcium_current" component_2="environment"/>
      <map_variables variable_1="time" variable_2="time"/>
   </connection>
   <connection>
      <map_components component_1="cationic_nonselective_inward_current" component_2="environment"/>
      <map_variables variable_1="time" variable_2="time"/>
   </connection>
   <connection>
      <map_components component_1="delayed_rectifier_K_channel_current" component_2="environment"/>
      <map_variables variable_1="time" variable_2="time"/>
   </connection>
   <connection>
      <map_components component_1="Ca_sensitive_K_current" component_2="environment"/>
      <map_variables variable_1="time" variable_2="time"/>
   </connection>
   <connection>
      <map_components component_1="ATP_sensitive_K_current" component_2="environment"/>
      <map_variables variable_1="time" variable_2="time"/>
   </connection>
   <connection>
      <map_components component_1="Na_leak_current" component_2="environment"/>
      <map_variables variable_1="time" variable_2="time"/>
   </connection>
   <connection>
      <map_components component_1="cytosolic_calcium" component_2="environment"/>
      <map_variables variable_1="time" variable_2="time"/>
   </connection>
   <connection>
      <map_components component_1="fast_current" component_2="membrane"/>
      <map_variables variable_1="V" variable_2="V"/>
      <map_variables variable_1="i_fast" variable_2="i_fast"/>
   </connection>
   <connection>
      <map_components component_1="calcium_current" component_2="membrane"/>
      <map_variables variable_1="V" variable_2="V"/>
      <map_variables variable_1="i_Ca" variable_2="i_Ca"/>
      <map_variables variable_1="R" variable_2="R"/>
      <map_variables variable_1="T" variable_2="T"/>
      <map_variables variable_1="F" variable_2="F"/>
   </connection>
   <connection>
      <map_components component_1="cationic_nonselective_inward_current" component_2="membrane"/>
      <map_variables variable_1="V" variable_2="V"/>
      <map_variables variable_1="i_NS" variable_2="i_NS"/>
   </connection>
   <connection>
      <map_components component_1="delayed_rectifier_K_channel_current" component_2="membrane"/>
      <map_variables variable_1="V" variable_2="V"/>
      <map_variables variable_1="i_K_dr" variable_2="i_K_dr"/>
   </connection>
   <connection>
      <map_components component_1="Ca_sensitive_K_current" component_2="membrane"/>
      <map_variables variable_1="V" variable_2="V"/>
      <map_variables variable_1="i_K_Ca" variable_2="i_K_Ca"/>
   </connection>
   <connection>
      <map_components component_1="ATP_sensitive_K_current" component_2="membrane"/>
      <map_variables variable_1="V" variable_2="V"/>
      <map_variables variable_1="i_K_ATP" variable_2="i_K_ATP"/>
   </connection>
   <connection>
      <map_components component_1="Na_leak_current" component_2="membrane"/>
      <map_variables variable_1="V" variable_2="V"/>
      <map_variables variable_1="i_NaL" variable_2="i_NaL"/>
   </connection>
   <connection>
      <map_components component_1="calcium_current" component_2="cytosolic_calcium"/>
      <map_variables variable_1="i_Ca" variable_2="i_Ca"/>
      <map_variables variable_1="Ca_i" variable_2="Ca_i"/>
   </connection>
   <connection>
      <map_components component_1="Ca_sensitive_K_current" component_2="cytosolic_calcium"/>
      <map_variables variable_1="Ca_i" variable_2="Ca_i"/>
   </connection>
   <connection>
      <map_components component_1="calcium_current" component_2="Ca_sensitive_K_current"/>
      <map_variables variable_1="K_Ca" variable_2="K_Ca"/>
   </connection>
   <connection>
      <map_components component_1="delayed_rectifier_K_channel_current" component_2="ATP_sensitive_K_current"/>
      <map_variables variable_1="V_K" variable_2="V_K"/>
   </connection>
   <connection>
      <map_components component_1="delayed_rectifier_K_channel_current" component_2="Ca_sensitive_K_current"/>
      <map_variables variable_1="V_K" variable_2="V_K"/>
   </connection>
   <connection>
      <map_components component_1="cationic_nonselective_inward_current" component_2="cytosolic_calcium"/>
      <map_variables variable_1="Ca_lum" variable_2="Ca_lum"/>
   </connection>
   <connection>
      <map_components component_1="fast_current" component_2="fast_current_m_gate"/>
      <map_variables variable_1="m_infinity" variable_2="m_infinity"/>
      <map_variables variable_1="time" variable_2="time"/>
      <map_variables variable_1="V" variable_2="V"/>
   </connection>
   <connection>
      <map_components component_1="fast_current" component_2="fast_current_h_gate"/>
      <map_variables variable_1="h" variable_2="h"/>
      <map_variables variable_1="time" variable_2="time"/>
      <map_variables variable_1="V" variable_2="V"/>
   </connection>
   <connection>
      <map_components component_1="calcium_current" component_2="calcium_current_f_gate"/>
      <map_variables variable_1="f_infinity" variable_2="f_infinity"/>
      <map_variables variable_1="Ca_i" variable_2="Ca_i"/>
      <map_variables variable_1="K_Ca" variable_2="K_Ca"/>
   </connection>
   <connection>
      <map_components component_1="calcium_current" component_2="calcium_current_d_gate"/>
      <map_variables variable_1="d" variable_2="d"/>
      <map_variables variable_1="time" variable_2="time"/>
      <map_variables variable_1="V" variable_2="V"/>
   </connection>
   <connection>
      <map_components component_1="delayed_rectifier_K_channel_current" component_2="delayed_rectifier_K_channel_current_n_gate"/>
      <map_variables variable_1="n" variable_2="n"/>
      <map_variables variable_1="time" variable_2="time"/>
      <map_variables variable_1="V" variable_2="V"/>
   </connection>






<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
  <rdf:Bag rdf:about="rdf:#a2cc4365-2f2f-4903-9cbc-dc863978ea00">
    <rdf:li>insulin</rdf:li>
    <rdf:li>calcium dynamics</rdf:li>
    <rdf:li>electrophysiology</rdf:li>
    <rdf:li>beta cell</rdf:li>
    <rdf:li>electrophysiological</rdf:li>
    <rdf:li>pancreas</rdf:li>
  </rdf:Bag>
  <rdf:Seq rdf:about="rdf:#bc06bd16-6e67-4d77-a80d-2be26c39d66a">
    <rdf:li rdf:resource="rdf:#c8ed2743-e461-42ca-a73a-827ce8fcd2ad"/>
  </rdf:Seq>
  <rdf:Description rdf:about="rdf:#871c6661-48e8-4650-b3b5-bfad56b05698">
    <vCard:FN xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">Catherine Lloyd</vCard:FN>
  </rdf:Description>
  <rdf:Description rdf:about="">
    <dc:publisher xmlns:dc="http://purl.org/dc/elements/1.1/">The University of Auckland, Bioengineering Institute</dc:publisher>
    <cmeta:comment rdf:resource="rdf:#78ee3dd1-395f-4641-977f-daebb0fd0000"/>
    <dcterms:created xmlns:dcterms="http://purl.org/dc/terms/" rdf:resource="rdf:#671ac0ed-af2c-4731-a741-4789876b0d5b"/>
    <dc:creator xmlns:dc="http://purl.org/dc/elements/1.1/" rdf:resource="rdf:#ff9885dd-8329-4566-90ce-9cb51418006c"/>
    <cmeta:modification rdf:resource="rdf:#8db5498a-7a29-4225-a8be-37914054e146"/>
    <cmeta:modification rdf:resource="rdf:#463030a1-9c73-4da9-9b90-71263df03307"/>
    <cmeta:modification rdf:resource="rdf:#a9e42612-b725-4ad8-9afa-a890ed4f3591"/>
    <cmeta:modification rdf:resource="rdf:#d42f3492-3ace-4f88-b29a-67b923201a1e"/>
    <cmeta:modification rdf:resource="rdf:#f0b2acc8-21ca-4887-9cbf-715041bcbc45"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#272ea005-0b0b-45fb-a45a-3f7efecb9fea">
    <dcterms:W3CDTF xmlns:dcterms="http://purl.org/dc/terms/">2007-06-19T11:36:53+12:00</dcterms:W3CDTF>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#9957dbbd-a1b4-40c7-b49e-502606ec0c36">
    <vCard:Given xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">James</vCard:Given>
    <vCard:Family xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">Lawson</vCard:Family>
    <vCard:Other xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">Richard</vCard:Other>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#adedec42-59c5-4dad-8f6c-177511d9560d">
    <dcterms:W3CDTF xmlns:dcterms="http://purl.org/dc/terms/">2002-07-22</dcterms:W3CDTF>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#2ff7ea09-d70f-436d-b123-483244b9fe0d">
    <dcterms:W3CDTF xmlns:dcterms="http://purl.org/dc/terms/">2009-05-29T14:58:14+12:00</dcterms:W3CDTF>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#1df83312-5912-493b-8df9-acad7a980fbc">
    <vCard:N xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#" rdf:resource="rdf:#b87b0808-5081-44e3-9bde-1b28762f3c10"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#1ae4fd8c-1a71-4896-a593-9393f8799835">
    <bqs:Pubmed_id xmlns:bqs="http://www.cellml.org/bqs/1.0#">9284334</bqs:Pubmed_id>
    <bqs:JournalArticle xmlns:bqs="http://www.cellml.org/bqs/1.0#" rdf:resource="rdf:#0c711e21-217a-4caf-ab74-c759ffaf1c48"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#b6ea36ce-7211-433b-b3c4-73bb7b83af1f">
    <vCard:Orgname xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">The University of Auckland</vCard:Orgname>
    <vCard:Orgunit xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">The Bioengineering Institute</vCard:Orgunit>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#ccfe63c1-73c7-4123-a339-173924cb7af6">
    <dc:creator xmlns:dc="http://purl.org/dc/elements/1.1/" rdf:resource="rdf:#871c6661-48e8-4650-b3b5-bfad56b05698"/>
    <rdf:value>This is the CellML description of Chay et al's 1997 mathematical model           of the effects of extracellular and intracellular calcium on pancreatic beta cells.</rdf:value>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#e5070e94-6bd9-4e8d-a860-997bc55aac36">
    <dcterms:W3CDTF xmlns:dcterms="http://purl.org/dc/terms/">2007-11-27T15:49:51+13:00</dcterms:W3CDTF>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#8db5498a-7a29-4225-a8be-37914054e146">
    <dcterms:modified xmlns:dcterms="http://purl.org/dc/terms/" rdf:resource="rdf:#2ff7ea09-d70f-436d-b123-483244b9fe0d"/>
    <rdf:value>updated curation status, removed reference link from documentation</rdf:value>
    <cmeta:modifier rdf:resource="rdf:#d6aeccde-f29c-47e6-b2d6-7cf9e8e3523a"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#58390b2b-86cc-4d41-a65f-ae3dbfa61add">
    <vCard:Given xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">Penny</vCard:Given>
    <vCard:Family xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">Noble</vCard:Family>
    <vCard:Other xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">J</vCard:Other>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#3f00c2b6-0292-4510-9d7a-5d1656bedfff">
    <dc:title xmlns:dc="http://purl.org/dc/elements/1.1/">Biophysical Journal</dc:title>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#c8ed2743-e461-42ca-a73a-827ce8fcd2ad">
    <rdf:type rdf:resource="http://www.cellml.org/bqs/1.0#Person"/>
    <vCard:N xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#" rdf:resource="rdf:#ac28220c-dc7d-4675-a1f8-e96ab61711c1"/>
  </rdf:Description>
  <rdf:Description rdf:about="#chay_1997">
    <ns7:simulation xmlns:ns7="http://www.cellml.org/metadata/simulation/1.0#" rdf:resource="rdf:#$szI6R1"/>
    <dc:title xmlns:dc="http://purl.org/dc/elements/1.1/">The Chay et al 1997 mathematical model of the effects of extracellular 
        and intracellular calcium on pancreatic beta cells.</dc:title>
    <cmeta:bio_entity>Pancreatic Beta-cell</cmeta:bio_entity>
    <cmeta:comment rdf:resource="rdf:#ccfe63c1-73c7-4123-a339-173924cb7af6"/>
    <bqs:reference xmlns:bqs="http://www.cellml.org/bqs/1.0#" rdf:resource="rdf:#0855ba44-9c92-4224-8182-c79ef9d998e0"/>
    <bqs:reference xmlns:bqs="http://www.cellml.org/bqs/1.0#" rdf:resource="rdf:#1ae4fd8c-1a71-4896-a593-9393f8799835"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#671ac0ed-af2c-4731-a741-4789876b0d5b">
    <dcterms:W3CDTF xmlns:dcterms="http://purl.org/dc/terms/">2002-05-07T00:00:00+00:00</dcterms:W3CDTF>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#3ee27592-159c-4faa-9c7a-22d32346dc0b">
    <dcterms:W3CDTF xmlns:dcterms="http://purl.org/dc/terms/">2003-04-09</dcterms:W3CDTF>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#ece923a6-30c1-47a9-b3b1-3909eda215f2">
    <vCard:FN xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">James Lawson</vCard:FN>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#d42f3492-3ace-4f88-b29a-67b923201a1e">
    <dcterms:modified xmlns:dcterms="http://purl.org/dc/terms/" rdf:resource="rdf:#adedec42-59c5-4dad-8f6c-177511d9560d"/>
    <rdf:value>Added more metadata.</rdf:value>
    <cmeta:modifier rdf:resource="rdf:#1df83312-5912-493b-8df9-acad7a980fbc"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#9ce2cfb8-26d1-4434-a964-2ec9582e1204">
    <vCard:Given xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">Catherine</vCard:Given>
    <vCard:Family xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">Lloyd</vCard:Family>
    <vCard:Other xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">May</vCard:Other>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#f0b2acc8-21ca-4887-9cbf-715041bcbc45">
    <dcterms:modified xmlns:dcterms="http://purl.org/dc/terms/" rdf:resource="rdf:#272ea005-0b0b-45fb-a45a-3f7efecb9fea"/>
    <rdf:value>Added cmeta:id's to several variables to allow their use by a session file. (PCEnv does this automatically when a session of a model is exported and the model file saved.)</rdf:value>
    <cmeta:modifier rdf:resource="rdf:#c3e37a47-326f-4f3c-81bc-def220c86f52"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#b87b0808-5081-44e3-9bde-1b28762f3c10">
    <vCard:Given xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">Catherine</vCard:Given>
    <vCard:Family xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">Lloyd</vCard:Family>
    <vCard:Other xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">May</vCard:Other>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#0c711e21-217a-4caf-ab74-c759ffaf1c48">
    <dc:creator xmlns:dc="http://purl.org/dc/elements/1.1/" rdf:resource="rdf:#bc06bd16-6e67-4d77-a80d-2be26c39d66a"/>
    <dc:title xmlns:dc="http://purl.org/dc/elements/1.1/">Effects of extracellular calcium on electrical bursting and                      intracellular and luminal calcium oscillations in insulin secreting              pancreatic beta-cells</dc:title>
    <bqs:volume xmlns:bqs="http://www.cellml.org/bqs/1.0#">73</bqs:volume>
    <bqs:first_page xmlns:bqs="http://www.cellml.org/bqs/1.0#">1673</bqs:first_page>
    <bqs:Journal xmlns:bqs="http://www.cellml.org/bqs/1.0#" rdf:resource="rdf:#3f00c2b6-0292-4510-9d7a-5d1656bedfff"/>
    <dcterms:issued xmlns:dcterms="http://purl.org/dc/terms/" rdf:resource="rdf:#12a2d14a-4cbc-4962-8793-966a6b2cee3a"/>
    <bqs:last_page xmlns:bqs="http://www.cellml.org/bqs/1.0#">1688</bqs:last_page>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#78ee3dd1-395f-4641-977f-daebb0fd0000">
    <dc:creator xmlns:dc="http://purl.org/dc/elements/1.1/" rdf:resource="rdf:#ece923a6-30c1-47a9-b3b1-3909eda215f2"/>
    <rdf:value>This model runs in PCEnv and COR and is able to reproduce the figures presented in the Chay 1997 paper. This version has a PCEnv session file associated with it. 

The session shows three electrophysiological graphs (x-axis is time in seconds): membrane potential (mV), intracellular cytosolic calcium and intracellular (luminal / endoplasmic reticulum) calcium. The value for the variable 'Ca_o' in the component 'calcium_current' can be altered to 0, 2.5, 5 or 7.5 mM to reproduce figures 5 a,b,c,d, respectively.</rdf:value>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#092f5120-d5e6-42cb-802c-44e04672abe8">
    <vCard:Given xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">James</vCard:Given>
    <vCard:Family xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">Lawson</vCard:Family>
    <vCard:Other xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">Richard</vCard:Other>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#$szI6R1">
    <ns7:boundIntervals xmlns:ns7="http://www.cellml.org/metadata/simulation/1.0#" rdf:resource="rdf:#$tzI6R1"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#ac28220c-dc7d-4675-a1f8-e96ab61711c1">
    <vCard:Given xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">Teresa</vCard:Given>
    <vCard:Family xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">Chay</vCard:Family>
    <vCard:Other xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">Ree</vCard:Other>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#54dc0efc-e194-433f-9ad9-cc28c0acf72b">
    <rdf:type rdf:resource="http://imc.org/vCard/3.0#internet"/>
    <rdf:value>c.lloyd@auckland.ac.nz</rdf:value>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#ff9885dd-8329-4566-90ce-9cb51418006c">
    <vCard:ORG xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#" rdf:resource="rdf:#b6ea36ce-7211-433b-b3c4-73bb7b83af1f"/>
    <vCard:EMAIL xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#" rdf:resource="rdf:#54dc0efc-e194-433f-9ad9-cc28c0acf72b"/>
    <vCard:N xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#" rdf:resource="rdf:#9ce2cfb8-26d1-4434-a964-2ec9582e1204"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#4f813ce0-f7d1-4d70-a28b-fa9487d2abf9">
    <vCard:N xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#" rdf:resource="rdf:#58390b2b-86cc-4d41-a65f-ae3dbfa61add"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#a9e42612-b725-4ad8-9afa-a890ed4f3591">
    <dcterms:modified xmlns:dcterms="http://purl.org/dc/terms/" rdf:resource="rdf:#3ee27592-159c-4faa-9c7a-22d32346dc0b"/>
    <rdf:value>Added publication date information.</rdf:value>
    <cmeta:modifier rdf:resource="rdf:#c963df5c-bb43-490d-baa3-587ac6d67bb0"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#463030a1-9c73-4da9-9b90-71263df03307">
    <dcterms:modified xmlns:dcterms="http://purl.org/dc/terms/" rdf:resource="rdf:#e5070e94-6bd9-4e8d-a860-997bc55aac36"/>
    <rdf:value>Units checked, curated.</rdf:value>
    <cmeta:modifier rdf:resource="rdf:#4f813ce0-f7d1-4d70-a28b-fa9487d2abf9"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#$tzI6R1">
    <rdf:rest rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#nil"/>
    <rdf:first rdf:resource="rdf:#$uzI6R1"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#$uzI6R1">
    <ns7:endingValue xmlns:ns7="http://www.cellml.org/metadata/simulation/1.0#">100</ns7:endingValue>
    <ns7:nonstandard-pointDensity xmlns:ns7="http://www.cellml.org/metadata/simulation/1.0#">1000000</ns7:nonstandard-pointDensity>
    <ns7:maximumStepSize xmlns:ns7="http://www.cellml.org/metadata/simulation/1.0#">0.01</ns7:maximumStepSize>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#12a2d14a-4cbc-4962-8793-966a6b2cee3a">
    <dcterms:W3CDTF xmlns:dcterms="http://purl.org/dc/terms/">1997-09</dcterms:W3CDTF>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#6bfba5f6-415b-466a-aff1-49fd37869b6e">
    <bqs:subject_type xmlns:bqs="http://www.cellml.org/bqs/1.0#">keyword</bqs:subject_type>
    <rdf:value rdf:resource="rdf:#a2cc4365-2f2f-4903-9cbc-dc863978ea00"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#0855ba44-9c92-4224-8182-c79ef9d998e0">
    <dc:subject xmlns:dc="http://purl.org/dc/elements/1.1/" rdf:resource="rdf:#6bfba5f6-415b-466a-aff1-49fd37869b6e"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#c3e37a47-326f-4f3c-81bc-def220c86f52">
    <vCard:N xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#" rdf:resource="rdf:#9957dbbd-a1b4-40c7-b49e-502606ec0c36"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#8180d95a-0164-47c3-bb69-9939c6a0c5ec">
    <vCard:Given xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">Autumn</vCard:Given>
    <vCard:Family xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">Cuellar</vCard:Family>
    <vCard:Other xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#">A</vCard:Other>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#d6aeccde-f29c-47e6-b2d6-7cf9e8e3523a">
    <vCard:N xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#" rdf:resource="rdf:#092f5120-d5e6-42cb-802c-44e04672abe8"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#c963df5c-bb43-490d-baa3-587ac6d67bb0">
    <vCard:N xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#" rdf:resource="rdf:#8180d95a-0164-47c3-bb69-9939c6a0c5ec"/>
  </rdf:Description>
</rdf:RDF>
</model>