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Comparison of Simulated and Measured Calcium Sparks in Intact Skeletal Muscle Fibers of the Frog
The CellML code.
<!-- FILE :baylor_model_b_2002_version02.xml
CREATED : 23rd May 2007
LAST MODIFIED : 23rd May 2007
AUTHOR : Catherine Lloyd
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 Baylor, Hollingworth and Chandler's 2002 model of the Ca2+-ATP binding reaction in skeletal myocytes.
CHANGES:
-->
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<article>
<articleinfo>
<title>Calcium Sparks in Skeletal Muscle Fibers</title>
<author>
<firstname>Catherine</firstname>
<surname>Lloyd</surname>
<affiliation>
<shortaffil>Bioengineering Institute, University of Auckland</shortaffil>
</affiliation>
</author>
</articleinfo>
<sect1 id="sec_structure">
<title>Model Structure</title>
<para>
The activation of Ca<superscript>2+</superscript> sparks is an essential step in cardiac excitation-contraction coupling. A Ca<superscript>2+</superscript> spark arises when sarcoplasmic reticulum (SR) Ca<superscript>2+</superscript>-release channels (ryanodine receptors, or RyRs) open, allowing Ca<superscript>2+</superscript> to diffuse out of the intracellular store, down its electrochemical gradient into the cytoplasm. The increase in intracellular calcium concentration ([Ca<superscript>2+</superscript>]<subscript>i</subscript>) is recognised as a Ca<superscript>2+</superscript> spark. After release, Ca<superscript>2+</superscript> diffuses through the cytoplasm and binds to buffers such as troponin, ATP, parvalbumin and the SR Ca<superscript>2+</superscript> pump.
</para>
<para>
In their 2002 paper, S.M. Baylor, S. Hollingworth and W.K. Chandler model Ca<superscript>2+</superscript> sparks in frog intact skeletal muscle fibers. The model calculates changes in the concentration of free Ca<superscript>2+</superscript> and of Ca<superscript>2+</superscript> bound to the buffers and to the Ca<superscript>2+</superscript> indicator fluo-3 (see <xref linkend="fig_reaction_diagram" /> below).
</para>
<para>
The complete original paper reference is cited below:
</para>
<para>
<ulink url="http://www.jgp.org/cgi/content/abstract/120/3/349">Comparison of Simulated and Measured Calcium Sparks in Intact Skeletal Muscle Fibers of the Frog</ulink>, S.M. Baylor, S. Hollingworth and W.K. Chandler, 2002, <ulink url="http://www.jgp.org/">
<emphasis>Journal of General Physiology</emphasis>
</ulink>, 120, 349-368. (<ulink url="http://www.jgp.org/cgi/content/full/120/3/349">Full text</ulink> and <ulink url="http://www.jgp.org/cgi/reprint/120/3/349.pdf">PDF versions</ulink> of the article are available to subscribers on the Journal of General Physiology website.) <ulink url="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12198091&dopt=Abstract">PubMed ID: 12198091</ulink>
</para>
<para>
The raw CellML descriptions of the model can be downloaded in various formats as described in <xref linkend="sec_download_this_model" />.
</para>
<informalfigure float="0" id="fig_reaction_diagram">
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<title>reaction_diagram</title>
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<imagedata fileref="../images/baylor_model_2002/reaction_diagram.gif" />
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<caption>Schematic diagrams of the Ca<superscript>2+</superscript> binding reactions for various buffers and indicators: <emphasis role="bold">A</emphasis> The reaction of Ca<superscript>2+</superscript> with ATP in the presence of free Mg<superscript>2+</superscript>, <emphasis role="bold">B</emphasis> Reaction of Ca<superscript>2+</superscript> with protein (Pr) and fluo-3 (Fluo), <emphasis role="bold">C</emphasis> Competitive reaction of Ca<superscript>2+</superscript> and Mg<superscript>2+</superscript> with parvalbumin (Parv), <emphasis role="bold">D</emphasis> Binding reaction of Ca<superscript>2+</superscript> binding and transport by the sarcoplasmic reticulum Ca<superscript>2+</superscript> pump (E), <emphasis role="bold">E</emphasis> One-step reaction of Ca<superscript>2+</superscript> with Troponin (Trop), and <emphasis role="bold">F</emphasis> Two-step reaction of Ca<superscript>2+</superscript> with Troponin (Trop).</caption>
</informalfigure>
</sect1>
</article>
</documentation>
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CREATED : 23rd May 2007
LAST MODIFIED : 23rd May 2007
AUTHOR : Catherine Lloyd
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 Baylor, Hollingworth and Chandler's 2002 model of the Ca2+-ATP binding reaction in skeletal myocytes.
CHANGES:
-->
<model xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#" xmlns:dcterms="http://purl.org/dc/terms/" xmlns:cellml="http://www.cellml.org/cellml/1.0#" xmlns:bqs="http://www.cellml.org/bqs/1.0#" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:cmeta="http://www.cellml.org/metadata/1.0#" xmlns="http://www.cellml.org/cellml/1.0#" cmeta:id="baylor_model_b_2002_version02" name="baylor_model_f_2002">
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<article>
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<title>Calcium Sparks in Skeletal Muscle Fibers</title>
<author>
<firstname>Catherine</firstname>
<surname>Lloyd</surname>
<affiliation>
<shortaffil>Bioengineering Institute, University of Auckland</shortaffil>
</affiliation>
</author>
</articleinfo>
<sect1 id="sec_structure">
<title>Model Structure</title>
<para>
The activation of Ca<superscript>2+</superscript> sparks is an essential step in cardiac excitation-contraction coupling. A Ca<superscript>2+</superscript> spark arises when sarcoplasmic reticulum (SR) Ca<superscript>2+</superscript>-release channels (ryanodine receptors, or RyRs) open, allowing Ca<superscript>2+</superscript> to diffuse out of the intracellular store, down its electrochemical gradient into the cytoplasm. The increase in intracellular calcium concentration ([Ca<superscript>2+</superscript>]<subscript>i</subscript>) is recognised as a Ca<superscript>2+</superscript> spark. After release, Ca<superscript>2+</superscript> diffuses through the cytoplasm and binds to buffers such as troponin, ATP, parvalbumin and the SR Ca<superscript>2+</superscript> pump.
</para>
<para>
In their 2002 paper, S.M. Baylor, S. Hollingworth and W.K. Chandler model Ca<superscript>2+</superscript> sparks in frog intact skeletal muscle fibers. The model calculates changes in the concentration of free Ca<superscript>2+</superscript> and of Ca<superscript>2+</superscript> bound to the buffers and to the Ca<superscript>2+</superscript> indicator fluo-3 (see <xref linkend="fig_reaction_diagram" /> below).
</para>
<para>
The complete original paper reference is cited below:
</para>
<para>
<ulink url="http://www.jgp.org/cgi/content/abstract/120/3/349">Comparison of Simulated and Measured Calcium Sparks in Intact Skeletal Muscle Fibers of the Frog</ulink>, S.M. Baylor, S. Hollingworth and W.K. Chandler, 2002, <ulink url="http://www.jgp.org/">
<emphasis>Journal of General Physiology</emphasis>
</ulink>, 120, 349-368. (<ulink url="http://www.jgp.org/cgi/content/full/120/3/349">Full text</ulink> and <ulink url="http://www.jgp.org/cgi/reprint/120/3/349.pdf">PDF versions</ulink> of the article are available to subscribers on the Journal of General Physiology website.) <ulink url="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12198091&dopt=Abstract">PubMed ID: 12198091</ulink>
</para>
<para>
The raw CellML descriptions of the model can be downloaded in various formats as described in <xref linkend="sec_download_this_model" />.
</para>
<informalfigure float="0" id="fig_reaction_diagram">
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<title>reaction_diagram</title>
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<imagedata fileref="../images/baylor_model_2002/reaction_diagram.gif" />
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<caption>Schematic diagrams of the Ca<superscript>2+</superscript> binding reactions for various buffers and indicators: <emphasis role="bold">A</emphasis> The reaction of Ca<superscript>2+</superscript> with ATP in the presence of free Mg<superscript>2+</superscript>, <emphasis role="bold">B</emphasis> Reaction of Ca<superscript>2+</superscript> with protein (Pr) and fluo-3 (Fluo), <emphasis role="bold">C</emphasis> Competitive reaction of Ca<superscript>2+</superscript> and Mg<superscript>2+</superscript> with parvalbumin (Parv), <emphasis role="bold">D</emphasis> Binding reaction of Ca<superscript>2+</superscript> binding and transport by the sarcoplasmic reticulum Ca<superscript>2+</superscript> pump (E), <emphasis role="bold">E</emphasis> One-step reaction of Ca<superscript>2+</superscript> with Troponin (Trop), and <emphasis role="bold">F</emphasis> Two-step reaction of Ca<superscript>2+</superscript> with Troponin (Trop).</caption>
</informalfigure>
</sect1>
</article>
</documentation>
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