Rendering of the source text

<?xml version="1.0" encoding="utf-8"?>
<!--
This CellML file was generated on 11/05/2010 at 12:35:43 at p.m. using:

COR (0.9.31.1371)
Copyright 2002-2010 Dr Alan Garny
http://cor.physiol.ox.ac.uk/ - cor@physiol.ox.ac.uk

CellML 1.0 was used to generate this model
http://www.cellml.org/
-->
<model xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:bqs="http://www.cellml.org/bqs/1.0#" xmlns:dcterms="http://purl.org/dc/terms/" xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#" name="stern_1999" cmeta:id="stern_1999" xmlns="http://www.cellml.org/cellml/1.0#" xmlns:cellml="http://www.cellml.org/cellml/1.0#" xmlns:cmeta="http://www.cellml.org/metadata/1.0#">
	<documentation xmlns="http://cellml.org/tmp-documentation">
		<article>
			<articleinfo>
				<title>Ryanodine Receptor Gating Kinetics in Cardiac Muscle</title>
				<author>
					<firstname>Catherine</firstname>
					<surname>Lloyd</surname>
					<affiliation>
						<shortaffil>Auckland Bioengineering Institute, The University of Auckland</shortaffil>
					</affiliation>
				</author>
				</articleinfo>
				<section id="sec_status">
                  <title>Model Status</title>
					<para>
            This model runs in OpenCell and COR, and the units are consistent throughout. The current model only describes a single RyR gating scheme, while the paper tests different gating schemes coupled with other dyadic components to recreate ion flows. As these are not described in great depth, this model is likely to remain incomplete and unable to recreate published results. Initial conditions used here are guesses. 
          </para>
				</section>
  <sect1 id="sec_structure">
<title>Model Structure</title>
				<para>
ABSTRACT: In cardiac muscle, release of activator calcium from the sarcoplasmic reticulum occurs by calcium-induced calcium release through ryanodine receptors (RyRs), which are clustered in a dense, regular, two-dimensional lattice array at the diad junction. We simulated numerically the stochastic dynamics of RyRs and L-type sarcolemmal calcium channels interacting via calcium nano-domains in the junctional cleft. Four putative RyR gating schemes based on single-channel measurements in lipid bilayers all failed to give stable excitation-contraction coupling, due either to insufficiently strong inactivation to terminate locally regenerative calcium-induced calcium release or insufficient cooperativity to discriminate against RyR activation by background calcium. If the ryanodine receptor was represented, instead, by a phenomenological four-state gating scheme, with channel opening resulting from simultaneous binding of two Ca2+ ions, and either calcium-dependent or activation-linked inactivation, the simulations gave a good semiquantitative accounting for the macroscopic features of excitation-contraction coupling. It was possible to restore stability to a model based on a bilayer-derived gating scheme, by introducing allosteric interactions between nearest-neighbor RyRs so as to stabilize the inactivated state and produce cooperativity among calcium binding sites on different RyRs. Such allosteric coupling between RyRs may be a function of the foot process and lattice array, explaining their conservation during evolution.
</para>
				<para>
The original paper reference is cited below:
</para>
				<para>
Local Control Models of Cardiac Excitation-Contraction Coupling <emphasis>A Possible Role for Allosteric Interactions between Ryanodine Receptors</emphasis>, Michael D. Stern, Long-Sheng Song, Heping Cheng, James S.K. Sham, Huang Tian Yang, Kenneth R. Boheler and Eduardo Rios, 1999, <emphasis>The Journal Of General Physiology</emphasis>, 113, 469-489.  <ulink url="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&amp;db=PubMed&amp;list_uids=10051521&amp;dopt=Abstract">PubMed ID: 10051521</ulink>
				</para>
				
				<informalfigure float="0" id="fig_reaction_diagram">
					<mediaobject>
						<imageobject>
							<objectinfo>
								<title>Schematic diagram of the RyR models</title>
							</objectinfo>
							<imagedata fileref="stern_1999.png"/>
						</imageobject>
					</mediaobject>
					<caption>RyR gating scheme.</caption>
				</informalfigure>
			</sect1>
		</article>
	</documentation>
	<rdf:RDF>
		<rdf:Bag rdf:about="rdf:#3ea7433a-533c-441f-bab0-5084453ee48b">
			<rdf:li>calcium dynamics</rdf:li>
			<rdf:li>excitation-contraction coupling</rdf:li>
			<rdf:li>electrophysiology</rdf:li>
			<rdf:li>cardiac myocyte</rdf:li>
			<rdf:li>Cardiac Myocyte</rdf:li>
			<rdf:li>cardic</rdf:li>
			<rdf:li>ryanodine receptor</rdf:li>
		</rdf:Bag>
		<rdf:Seq rdf:about="rdf:#dc409d33-a6c1-4b27-8dbe-4c34495eb42e">
			<rdf:li rdf:resource="rdf:#c77896e9-763d-4cf9-bc5d-3fa42d70cef5"/>
			<rdf:li rdf:resource="rdf:#359a7d7e-e51e-442b-b4ab-547690c51d44"/>
			<rdf:li rdf:resource="rdf:#b63d0233-9e90-496f-9317-9c334571b8d6"/>
			<rdf:li rdf:resource="rdf:#c9137d23-c19c-4f86-9461-15766c5de40f"/>
			<rdf:li rdf:resource="rdf:#e3a4579d-08db-45c1-8236-c80570249b6f"/>
			<rdf:li rdf:resource="rdf:#a3c2cd73-25d3-4de5-9d15-dd0943e54d35"/>
		</rdf:Seq>
		<rdf:Description rdf:about="">
			<dc:publisher>The University of Auckland, Auckland Bioengineering Institute</dc:publisher>
			<cmeta:comment xmlns:cmeta="http://www.cellml.org/metadata/1.0#" rdf:resource="rdf:#2acfbc67-7e7a-4891-b8a8-0506d6d73fc3"/>
			<dcterms:created rdf:resource="rdf:#6a976a38-e6b5-4889-a33c-930b6f3625dc"/>
			<dc:creator rdf:resource="rdf:#0265258a-9d35-4532-9f3f-071a4a9a5163"/>
			<cmeta:modification xmlns:cmeta="http://www.cellml.org/metadata/1.0#" rdf:resource="rdf:#6d0cc074-4e1a-430c-8ecf-661c69fbaedf"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#61db99fa-f55b-467d-8932-f8b6ec95b61b">
			<dc:title>Journal of General Physiology</dc:title>
		</rdf:Description>
		<rdf:Description rdf:about="#I">
			<dcterms:alternative>Inactive state</dcterms:alternative>
			<dc:title>I</dc:title>
		</rdf:Description>
		<rdf:Description rdf:about="#O">
			<dcterms:alternative>Open state</dcterms:alternative>
			<dc:title>O</dc:title>
		</rdf:Description>
		<rdf:Description rdf:about="#R">
			<dcterms:alternative>Receptor</dcterms:alternative>
			<dc:title>R</dc:title>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#a3c2cd73-25d3-4de5-9d15-dd0943e54d35">
			<rdf:type rdf:resource="http://www.cellml.org/bqs/1.0#Person"/>
			<vCard:N rdf:resource="rdf:#26acc23f-0493-4270-8067-6fd8593f3eca"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#5220abb1-48ed-4e07-9bf7-7ad6079cdbe7">
			<dc:creator rdf:resource="rdf:#dc409d33-a6c1-4b27-8dbe-4c34495eb42e"/>
			<dc:title>Local Control Models of Cardiac Excitation-Contraction Coupling A Possible Role for Allosteric Interactions between Ryanodine Receptors</dc:title>
			<bqs:volume>113</bqs:volume>
			<bqs:first_page>469</bqs:first_page>
			<bqs:Journal rdf:resource="rdf:#61db99fa-f55b-467d-8932-f8b6ec95b61b"/>
			<dcterms:issued rdf:resource="rdf:#1c3bf761-4cb7-42e6-8857-e1b253f39e05"/>
			<bqs:last_page>498</bqs:last_page>
		</rdf:Description>
		<rdf:Description rdf:about="#stern_1999">
			<dc:title>
        Stern et al's 1999 model of a gating scheme for ryanodine receptors.
      </dc:title>
			<cmeta:bio_entity xmlns:cmeta="http://www.cellml.org/metadata/1.0#">Cardiac Myocyte</cmeta:bio_entity>
			<cmeta:comment xmlns:cmeta="http://www.cellml.org/metadata/1.0#" rdf:resource="rdf:#ef65f439-0d29-411d-8988-ce70863dfd6a"/>
			<bqs:reference rdf:resource="rdf:#58f03cff-0482-424e-aceb-6adb43d429c5"/>
			<bqs:reference rdf:resource="rdf:#e41230e0-0257-428b-9714-b50a18228a90"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#e41230e0-0257-428b-9714-b50a18228a90">
			<dc:subject rdf:resource="rdf:#fc0f1d6d-0a5c-4a38-bf64-70e3ac990f8d"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#fc0f1d6d-0a5c-4a38-bf64-70e3ac990f8d">
			<bqs:subject_type>keyword</bqs:subject_type>
			<rdf:value rdf:resource="rdf:#3ea7433a-533c-441f-bab0-5084453ee48b"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#c77896e9-763d-4cf9-bc5d-3fa42d70cef5">
			<rdf:type rdf:resource="http://www.cellml.org/bqs/1.0#Person"/>
			<vCard:N rdf:resource="rdf:#c65ea2b3-eb30-4499-9689-aab2227d3962"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#9fd515e4-13f3-4386-8f06-ea68f430b4d1">
			<vCard:N rdf:resource="rdf:#f2245791-8849-47f9-8648-63f5e2ec0a7d"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#c60676d5-4a65-4ba1-ad1e-09487222f1f3">
			<vCard:Given>Catherine</vCard:Given>
			<vCard:Family>Lloyd</vCard:Family>
			<vCard:Other>May</vCard:Other>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#61f4ef76-cfef-4fbd-aa15-668f6bc0f739">
			<vCard:Orgname>The University of Auckland</vCard:Orgname>
			<vCard:Orgunit>Auckland Bioengineering Institute</vCard:Orgunit>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#c65ea2b3-eb30-4499-9689-aab2227d3962">
			<vCard:Given>Michael</vCard:Given>
			<vCard:Family>Stern</vCard:Family>
			<vCard:Other>D</vCard:Other>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#26acc23f-0493-4270-8067-6fd8593f3eca">
			<vCard:Given>Eduardo</vCard:Given>
			<vCard:Family>Rios</vCard:Family>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#359a7d7e-e51e-442b-b4ab-547690c51d44">
			<rdf:type rdf:resource="http://www.cellml.org/bqs/1.0#Person"/>
			<vCard:N rdf:resource="rdf:#33d92d16-4320-47b6-a01e-1b824daaae2b"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#ef65f439-0d29-411d-8988-ce70863dfd6a">
			<dc:creator rdf:resource="rdf:#b8d87639-8ad3-4e28-afcc-9dd96c257b03"/>
			<rdf:value>This is the CellML description of Stern et al's 1999 model of a gating scheme for ryanodine receptors in cardiac muscle.</rdf:value>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#2acfbc67-7e7a-4891-b8a8-0506d6d73fc3">
			<dc:creator rdf:resource="rdf:#c6a1e4af-7419-44e1-880c-6f5f130c743c"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#f231a00f-6a6c-4258-ab49-d2a1b6edf237">
			<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:#33d92d16-4320-47b6-a01e-1b824daaae2b">
			<vCard:Given>Long-Sheng</vCard:Given>
			<vCard:Family>Song</vCard:Family>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#f2245791-8849-47f9-8648-63f5e2ec0a7d">
			<vCard:Given>Catherine</vCard:Given>
			<vCard:Family>Lloyd</vCard:Family>
			<vCard:Other>May</vCard:Other>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#0265258a-9d35-4532-9f3f-071a4a9a5163">
			<vCard:ORG rdf:resource="rdf:#61f4ef76-cfef-4fbd-aa15-668f6bc0f739"/>
			<vCard:EMAIL rdf:resource="rdf:#f231a00f-6a6c-4258-ab49-d2a1b6edf237"/>
			<vCard:N rdf:resource="rdf:#c60676d5-4a65-4ba1-ad1e-09487222f1f3"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#b8d87639-8ad3-4e28-afcc-9dd96c257b03">
			<vCard:FN>Catherine Lloyd</vCard:FN>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#6a976a38-e6b5-4889-a33c-930b6f3625dc">
			<dcterms:W3CDTF>2007-05-23T00:00:00+00:00</dcterms:W3CDTF>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#712b25c7-b350-4d98-a8f1-9fef7bf9c017">
			<vCard:Given>Huang</vCard:Given>
			<vCard:Family>Yang</vCard:Family>
			<vCard:Other>Tian</vCard:Other>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#58f03cff-0482-424e-aceb-6adb43d429c5">
			<bqs:Pubmed_id>10051521</bqs:Pubmed_id>
			<bqs:JournalArticle rdf:resource="rdf:#5220abb1-48ed-4e07-9bf7-7ad6079cdbe7"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#4cfb5e9b-a2cb-4a8f-bc49-9ee618486965">
			<vCard:Given>Kenneth</vCard:Given>
			<vCard:Family>Boheler</vCard:Family>
			<vCard:Other>R</vCard:Other>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#1c3bf761-4cb7-42e6-8857-e1b253f39e05">
			<dcterms:W3CDTF>1999-03-01</dcterms:W3CDTF>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#0b362a02-9130-4a03-87b0-a2adfbcdc066">
			<vCard:Given>James</vCard:Given>
			<vCard:Family>Sham</vCard:Family>
			<vCard:Other>K</vCard:Other>
			<vCard:Other>S</vCard:Other>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#49f2cc0c-7ab6-4631-a91d-41a740acc45f">
			<dcterms:W3CDTF>2007-06-05T10:46:00+12:00</dcterms:W3CDTF>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#c9137d23-c19c-4f86-9461-15766c5de40f">
			<rdf:type rdf:resource="http://www.cellml.org/bqs/1.0#Person"/>
			<vCard:N rdf:resource="rdf:#712b25c7-b350-4d98-a8f1-9fef7bf9c017"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#b63d0233-9e90-496f-9317-9c334571b8d6">
			<rdf:type rdf:resource="http://www.cellml.org/bqs/1.0#Person"/>
			<vCard:N rdf:resource="rdf:#0b362a02-9130-4a03-87b0-a2adfbcdc066"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#6d0cc074-4e1a-430c-8ecf-661c69fbaedf">
			<dcterms:modified rdf:resource="rdf:#49f2cc0c-7ab6-4631-a91d-41a740acc45f"/>
			<rdf:value>The new version of this model has been re-coded to remove the reaction element and replace it with a simple MathML description of the model reaction kinetics. This is thought to be truer to the original publication, and information regarding the enzyme kinetics etc will later be added to the metadata through use of an ontology. 

The model runs in the PCEnv simulator but gives a flat output.</rdf:value>
			<cmeta:modifier xmlns:cmeta="http://www.cellml.org/metadata/1.0#" rdf:resource="rdf:#9fd515e4-13f3-4386-8f06-ea68f430b4d1"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#e3a4579d-08db-45c1-8236-c80570249b6f">
			<rdf:type rdf:resource="http://www.cellml.org/bqs/1.0#Person"/>
			<vCard:N rdf:resource="rdf:#4cfb5e9b-a2cb-4a8f-bc49-9ee618486965"/>
		</rdf:Description>
	</rdf:RDF>   <units xmlns="http://www.cellml.org/cellml/1.0#" name="millimolar">
      <unit units="mole" prefix="milli"/>
      <unit units="litre" exponent="-1"/>
   </units>
   <units xmlns="http://www.cellml.org/cellml/1.0#" name="millisecond">
      <unit units="second" prefix="milli"/>
   </units>
   <units xmlns="http://www.cellml.org/cellml/1.0#" name="first_order_rate_constant">
      <unit units="millisecond" exponent="-1"/>
   </units>
   <units xmlns="http://www.cellml.org/cellml/1.0#" name="second_order_rate_constant">
      <unit units="millimolar" exponent="-1"/>
      <unit units="millisecond" exponent="-1"/>
   </units>
   <units xmlns="http://www.cellml.org/cellml/1.0#" name="third_order_rate_constant">
      <unit units="millimolar" exponent="-2"/>
      <unit units="millisecond" exponent="-1"/>
   </units>
   <component xmlns="http://www.cellml.org/cellml/1.0#" name="environment">
      <variable name="time" units="millisecond" public_interface="out"/>
   </component>
   <component xmlns="http://www.cellml.org/cellml/1.0#" name="R">
      <variable name="R" units="dimensionless" initial_value="1" public_interface="out"/>
      <variable name="ki" units="second_order_rate_constant" public_interface="in"/>
      <variable name="ko" units="third_order_rate_constant" public_interface="in"/>
      <variable name="kim" units="first_order_rate_constant" public_interface="in"/>
      <variable name="kom" units="first_order_rate_constant" public_interface="in"/>
      <variable name="RI" units="dimensionless" public_interface="in"/>
      <variable name="O" units="dimensionless" public_interface="in"/>
      <variable name="Ca" units="millimolar" public_interface="in"/>
      <variable name="time" units="millisecond" public_interface="in"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <apply>
               <diff/>
               <bvar>
                  <ci>time</ci>
               </bvar>
               <ci>R</ci>
            </apply>
            <apply>
               <minus/>
               <apply>
                  <plus/>
                  <apply>
                     <times/>
                     <ci>kom</ci>
                     <ci>O</ci>
                  </apply>
                  <apply>
                     <times/>
                     <ci>kim</ci>
                     <ci>RI</ci>
                  </apply>
               </apply>
               <apply>
                  <plus/>
                  <apply>
                     <times/>
                     <ci>ko</ci>
                     <apply>
                        <power/>
                        <ci>Ca</ci>
                        <cn cellml:units="dimensionless">2</cn>
                     </apply>
                     <ci>R</ci>
                  </apply>
                  <apply>
                     <times/>
                     <ci>ki</ci>
                     <ci>Ca</ci>
                     <ci>R</ci>
                  </apply>
               </apply>
            </apply>
         </apply>
      </math>
   </component>
   <component xmlns="http://www.cellml.org/cellml/1.0#" name="O">
      <variable name="O" units="dimensionless" initial_value="1" public_interface="out"/>
      <variable name="ki" units="second_order_rate_constant" public_interface="in"/>
      <variable name="ko" units="third_order_rate_constant" public_interface="in"/>
      <variable name="kim" units="first_order_rate_constant" public_interface="in"/>
      <variable name="kom" units="first_order_rate_constant" public_interface="in"/>
      <variable name="I" units="dimensionless" public_interface="in"/>
      <variable name="R" units="dimensionless" public_interface="in"/>
      <variable name="Ca" units="millimolar" public_interface="in"/>
      <variable name="time" units="millisecond" public_interface="in"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <apply>
               <diff/>
               <bvar>
                  <ci>time</ci>
               </bvar>
               <ci>O</ci>
            </apply>
            <apply>
               <minus/>
               <apply>
                  <plus/>
                  <apply>
                     <times/>
                     <ci>kim</ci>
                     <ci>I</ci>
                  </apply>
                  <apply>
                     <times/>
                     <ci>ko</ci>
                     <apply>
                        <power/>
                        <ci>Ca</ci>
                        <cn cellml:units="dimensionless">2</cn>
                     </apply>
                     <ci>R</ci>
                  </apply>
               </apply>
               <apply>
                  <plus/>
                  <apply>
                     <times/>
                     <ci>kom</ci>
                     <ci>O</ci>
                  </apply>
                  <apply>
                     <times/>
                     <ci>ki</ci>
                     <ci>Ca</ci>
                     <ci>O</ci>
                  </apply>
               </apply>
            </apply>
         </apply>
      </math>
   </component>
   <component xmlns="http://www.cellml.org/cellml/1.0#" name="I">
      <variable name="I" units="dimensionless" initial_value="1" public_interface="out"/>
      <variable name="ki" units="second_order_rate_constant" public_interface="in"/>
      <variable name="ko" units="third_order_rate_constant" public_interface="in"/>
      <variable name="kim" units="first_order_rate_constant" public_interface="in"/>
      <variable name="kom" units="first_order_rate_constant" public_interface="in"/>
      <variable name="O" units="dimensionless" public_interface="in"/>
      <variable name="RI" units="dimensionless" public_interface="in"/>
      <variable name="Ca" units="millimolar" public_interface="in"/>
      <variable name="time" units="millisecond" public_interface="in"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <apply>
               <diff/>
               <bvar>
                  <ci>time</ci>
               </bvar>
               <ci>I</ci>
            </apply>
            <apply>
               <minus/>
               <apply>
                  <plus/>
                  <apply>
                     <times/>
                     <ci>ki</ci>
                     <ci>Ca</ci>
                     <ci>O</ci>
                  </apply>
                  <apply>
                     <times/>
                     <ci>ko</ci>
                     <apply>
                        <power/>
                        <ci>Ca</ci>
                        <cn cellml:units="dimensionless">2</cn>
                     </apply>
                     <ci>RI</ci>
                  </apply>
               </apply>
               <apply>
                  <plus/>
                  <apply>
                     <times/>
                     <ci>kim</ci>
                     <ci>I</ci>
                  </apply>
                  <apply>
                     <times/>
                     <ci>kom</ci>
                     <ci>I</ci>
                  </apply>
               </apply>
            </apply>
         </apply>
      </math>
   </component>
   <component xmlns="http://www.cellml.org/cellml/1.0#" name="RI">
      <variable name="RI" units="dimensionless" initial_value="1" public_interface="out"/>
      <variable name="ki" units="second_order_rate_constant" public_interface="in"/>
      <variable name="ko" units="third_order_rate_constant" public_interface="in"/>
      <variable name="kim" units="first_order_rate_constant" public_interface="in"/>
      <variable name="kom" units="first_order_rate_constant" public_interface="in"/>
      <variable name="I" units="dimensionless" public_interface="in"/>
      <variable name="R" units="dimensionless" public_interface="in"/>
      <variable name="Ca" units="millimolar" public_interface="in"/>
      <variable name="time" units="millisecond" public_interface="in"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <apply>
               <diff/>
               <bvar>
                  <ci>time</ci>
               </bvar>
               <ci>RI</ci>
            </apply>
            <apply>
               <minus/>
               <apply>
                  <plus/>
                  <apply>
                     <times/>
                     <ci>ki</ci>
                     <ci>Ca</ci>
                     <ci>R</ci>
                  </apply>
                  <apply>
                     <times/>
                     <ci>kom</ci>
                     <ci>I</ci>
                  </apply>
               </apply>
               <apply>
                  <plus/>
                  <apply>
                     <times/>
                     <ci>kim</ci>
                     <ci>RI</ci>
                  </apply>
                  <apply>
                     <times/>
                     <ci>ko</ci>
                     <apply>
                        <power/>
                        <ci>Ca</ci>
                        <cn cellml:units="dimensionless">2</cn>
                     </apply>
                     <ci>RI</ci>
                  </apply>
               </apply>
            </apply>
         </apply>
      </math>
   </component>
   <component xmlns="http://www.cellml.org/cellml/1.0#" name="reaction_constants">
      <variable name="Ca" units="millimolar" initial_value="0.0001" public_interface="out"/>
      <variable name="ki" units="second_order_rate_constant" initial_value="0.5" public_interface="out"/>
      <variable name="ko" units="third_order_rate_constant" initial_value="35" public_interface="out"/>
      <variable name="kim" units="first_order_rate_constant" initial_value="0.005" public_interface="out"/>
      <variable name="kom" units="first_order_rate_constant" initial_value="0.06" public_interface="out"/>
   </component>
   <connection xmlns="http://www.cellml.org/cellml/1.0#">
      <map_components component_1="R" component_2="environment"/>
      <map_variables variable_1="time" variable_2="time"/>
   </connection>
   <connection xmlns="http://www.cellml.org/cellml/1.0#">
      <map_components component_1="O" component_2="environment"/>
      <map_variables variable_1="time" variable_2="time"/>
   </connection>
   <connection xmlns="http://www.cellml.org/cellml/1.0#">
      <map_components component_1="I" component_2="environment"/>
      <map_variables variable_1="time" variable_2="time"/>
   </connection>
   <connection xmlns="http://www.cellml.org/cellml/1.0#">
      <map_components component_1="RI" component_2="environment"/>
      <map_variables variable_1="time" variable_2="time"/>
   </connection>
   <connection xmlns="http://www.cellml.org/cellml/1.0#">
      <map_components component_1="R" component_2="O"/>
      <map_variables variable_1="R" variable_2="R"/>
      <map_variables variable_1="O" variable_2="O"/>
   </connection>
   <connection xmlns="http://www.cellml.org/cellml/1.0#">
      <map_components component_1="R" component_2="RI"/>
      <map_variables variable_1="R" variable_2="R"/>
      <map_variables variable_1="RI" variable_2="RI"/>
   </connection>
   <connection xmlns="http://www.cellml.org/cellml/1.0#">
      <map_components component_1="O" component_2="I"/>
      <map_variables variable_1="O" variable_2="O"/>
      <map_variables variable_1="I" variable_2="I"/>
   </connection>
   <connection xmlns="http://www.cellml.org/cellml/1.0#">
      <map_components component_1="I" component_2="RI"/>
      <map_variables variable_1="I" variable_2="I"/>
      <map_variables variable_1="RI" variable_2="RI"/>
   </connection>
   <connection xmlns="http://www.cellml.org/cellml/1.0#">
      <map_components component_1="R" component_2="reaction_constants"/>
      <map_variables variable_1="Ca" variable_2="Ca"/>
      <map_variables variable_1="ki" variable_2="ki"/>
      <map_variables variable_1="ko" variable_2="ko"/>
      <map_variables variable_1="kim" variable_2="kim"/>
      <map_variables variable_1="kom" variable_2="kom"/>
   </connection>
   <connection xmlns="http://www.cellml.org/cellml/1.0#">
      <map_components component_1="O" component_2="reaction_constants"/>
      <map_variables variable_1="Ca" variable_2="Ca"/>
      <map_variables variable_1="ki" variable_2="ki"/>
      <map_variables variable_1="ko" variable_2="ko"/>
      <map_variables variable_1="kim" variable_2="kim"/>
      <map_variables variable_1="kom" variable_2="kom"/>
   </connection>
   <connection xmlns="http://www.cellml.org/cellml/1.0#">
      <map_components component_1="I" component_2="reaction_constants"/>
      <map_variables variable_1="Ca" variable_2="Ca"/>
      <map_variables variable_1="ki" variable_2="ki"/>
      <map_variables variable_1="ko" variable_2="ko"/>
      <map_variables variable_1="kim" variable_2="kim"/>
      <map_variables variable_1="kom" variable_2="kom"/>
   </connection>
   <connection xmlns="http://www.cellml.org/cellml/1.0#">
      <map_components component_1="RI" component_2="reaction_constants"/>
      <map_variables variable_1="Ca" variable_2="Ca"/>
      <map_variables variable_1="ki" variable_2="ki"/>
      <map_variables variable_1="ko" variable_2="ko"/>
      <map_variables variable_1="kim" variable_2="kim"/>
      <map_variables variable_1="kom" variable_2="kom"/>
   </connection>
</model>