Location: Chang, Fujita, 2001 @ 3154891c06df / chang_fujita_2001_variant02.cellml

Author:
pmr2.import <nobody@models.cellml.org>
Date:
2009-06-17 12:44:46+12:00
Desc:
committing version02 of chang_fujita_2001
Permanent Source URI:
https://models.cellml.org/workspace/chang_fujita_2001/rawfile/3154891c06dfcd5cdb61375c7e916e39fa7d41d0/chang_fujita_2001_variant02.cellml

<?xml version='1.0' encoding='utf-8'?>
<!--  FILE :  renal_Na_H_exchanger_model.xml

CREATED :  29th May 2007

LAST MODIFIED : 29th May 2007

AUTHOR :  Catherine Lloyd
          The Bioengineering Institute
          The University of Auckland
          
MODEL STATUS :  This model conforms to the CellML 1.1 Specification.

DESCRIPTION :  This file contains a CellML description of Chang and Fujita's 2001 mathematical model of a Na-H exchanger in the distal tubule of the rat: it is one component of an overall model of acid/base transport in a distal tubule.

CHANGES:  
 
  
--><model xmlns="http://www.cellml.org/cellml/1.0#" xmlns:cmeta="http://www.cellml.org/metadata/1.0#" 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:cellml="http://www.cellml.org/cellml/1.0#" xmlns:dcterms="http://purl.org/dc/terms/" xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#" cmeta:id="renal_Na_H_exchanger_model_version02" name="chang_fujita_2001_version03">
<documentation xmlns="http://cellml.org/tmp-documentation">
<article>
  <articleinfo>
  <title>Mathematical Models of Ionic Transport in the Distal Tubule of the Rat</title>
  <author>
    <firstname>Catherine</firstname>
          <surname>Lloyd</surname>
    <affiliation>
      <shortaffil>Bioengineering Institute, University of Auckland</shortaffil>
    </affiliation>
  </author>
</articleinfo>
  <section id="sec_status">
    <title>Model Status</title>
    <para>
            This CellML model is a description of Chang and Fujita's 2001 mathematical model of a Na-H exchanger in the distal tubule of the rat: it is one component of an overall model of acid/base transport in a distal tubule.
          </para>
  </section>
  <sect1 id="sec_structure">
<title>Model Structure</title>

<para>
Acid-base transport in the rat distal tubule of the kidney has been extensively studied by a variety of different experimental methods.  These experiments have shown that in the early part of the distal tubule, H<superscript>+</superscript> is secreted into the tubular fluid via a Na/H exchanger embedded in the luminal membrane (see <xref linkend="fig_reaction_diagram1"/> below).  Closely linked with this process is the transport of HCO<subscript>3</subscript>
          <superscript>-</superscript> out of the cytosolic space into the basolateral space.  This probably occurs via an anion exchanger.  In the late distal tubule, distinct cell types called intercalated cells are present.  These cells are specifically involved in acid-base transport.  Type A cells secrete H<superscript>+</superscript> via a luminal H-ATPase, and they extrude HCO<subscript>3</subscript>
          <superscript>-</superscript> via a basolateral anion exchanger.  Type B cells have anion transporters on their opposite side, and they function to secrete HCO<subscript>3</subscript>
          <superscript>-</superscript> into the tubular fluid.    
</para>

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

<para>
<ulink url="http://ajprenal.physiology.org/cgi/content/abstract/281/2/F222">A numerical model of acid-base transport in rat distal tubule</ulink>, Hangil Chang and Toshiro Fujita, 2001, <ulink url="http://ajpcon.physiology.org/">
            <emphasis>American Journal of Physiology</emphasis>
          </ulink>, 281, F222-F243. (<ulink url="http://ajprenal.physiology.org/cgi/reprint/281/2/F222.pdf">PDF</ulink> and <ulink url="http://ajprenal.physiology.org/cgi/content/full/281/2/F222">text</ulink> versions of the article are available to Journal subscribers.  <ulink url="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&amp;db=PubMed&amp;list_uids=11457714&amp;dopt=Abstract">PubMed ID: 11457714</ulink>) 
</para>

<informalfigure float="0" id="fig_reaction_diagram1">
<mediaobject>
  <imageobject>
    <objectinfo>
      <title>reaction_diagram1</title>
    </objectinfo>
    <imagedata fileref="chang_2001a.png"/>
  </imageobject>
</mediaobject>
<caption>State diagram of the Na-H exchanger.  In this model, the Na-H exchanger has a single binding site (E) to which Na<superscript>+</superscript>, H<superscript>+</superscript>, and NH<subscript>4</subscript>
            <superscript>+</superscript> bind competitively.  Only the bound forms of the transporter are able to cross the membrane.  (Symbols with the asterisk (*) represent conformations facing the cytosol, symbols without indicate conformations facing the extracellular environment.)</caption>
</informalfigure>


</sect1>
</article>
</documentation>
  


  
  
  
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        <ci> k16 </ci>
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