Location: Drouhard, Roberge, 1987 @ 89d94d93a0cc / drouhard_roberge_1987.cellml

Author:
pmr2.import <nobody@models.cellml.org>
Date:
2006-09-04 03:04:06+12:00
Desc:
committing version01 of drouhard_roberge_1987
Permanent Source URI:
https://models.physiomeproject.org/workspace/drouhard_roberge_1987/rawfile/89d94d93a0ccb31c0cdcffb45de83e9083dc9e6a/drouhard_roberge_1987.cellml

<?xml version='1.0' encoding='utf-8'?>
<!-- FILE : drouhard_roberge_model_1987.xml

CREATED : 17th December 2001

LAST MODIFIED : 30th July 2003

AUTHOR : Catherine Lloyd
         Department of Engineering Science
         The University of Auckland
         
MODEL STATUS : This model conforms to the CellML 1.0 Specification released on
10th August 2001, and the 16/01/2002 CellML Metadata 1.0 Specification.

DESCRIPTION : This file contains a CellML description of the fast sodium current
in ventricular myocardial cells, based on the Drouhard-Roberge model, 1987. 

CHANGES:  
  04/01/2002 - CML - Added the components of the Beeler-Reuter Model.
  21/01/2002 - AAC - Updated metadata to conform to the 16/1/02 CellML Metadata
                     1.0 Specification.
  28/02/2002 - CML - Corrected the membrane voltage differential equation.
  19/07/2002 - CML - Added more metadata.
  09/04/2003 - AAC - Added publication date information. 
  30/07/2003 - CML - Changed equations. 
--><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="drouhard_roberge_1987_version01" name="drouhard_roberge_1987_version01">
<documentation xmlns="http://cellml.org/tmp-documentation">
<article>
  <articleinfo>
  <title>The Drouhard-Roberge Sodium Current Model (1987)</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 is the original unchecked version of the model imported from the previous
            CellML model repository, 24-Jan-2006.
          </para>
  </section>
  <sect1 id="sec_structure">
<title>Model Structure</title>

<para>
In 1987, Jean-Pierre Drouhard and Fernand A. Roberge published a revised formulation of the <ulink url="${HTML_EXMPL_HHSA_INTRO}">Hodgkin-Huxley representation</ulink> of the sodium current in ventricular myocardial cells.  Their improvements have ensured that the action potential upstroke is much faster, and in agreement with experimental observations the peak depolarisation is close to the sodium potential.  Like the <ulink url="${HTML_EXMPL_EJ_MODEL}">Ebihara-Johnson model (1980)</ulink>, the Drouhard-Roberge model can be used to replace the sodium kinetics of the <ulink url="${HTML_EXMPL_BR_MODEL}">Beeler-Reuter model (1977)</ulink>.
</para>

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

<para>
Revised Formulation of the Hodgkin-Huxley Representation of the Sodium Current in Cardiac Cells, Jean-Pierre Drouhard and Fernand A. Roberge, 1987, <ulink url="http://www.academicpress.com/jbi">
            <emphasis>Computers and Biomedical Research</emphasis>
          </ulink>, 20, 333-350.  <ulink url="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&amp;db=PubMed&amp;list_uids=3621918&amp;dopt=Abstract">PubMed ID: 3621918</ulink>
</para>

<para>
The raw CellML description of the Drouhard-Roberge model can be downloaded in various formats as described in <xref linkend="sec_download_this_model"/>.  For an example of a more complete documentation for an electrophysiological model, see <ulink url="${HTML_EXMPL_HHSA_INTRO}">The Hodgkin-Huxley Squid Axon Model, 1952</ulink>. 
</para>
</sect1>
</article>
</documentation>
  
  
  <!--
    Below, we define some additional units for association with variables and
    constants within the model. The identifiers are fairly self-explanatory.
  -->
  <units name="millisecond">
    <unit units="second" prefix="milli"/>
  </units>
  
  <units name="per_millisecond">
    <unit units="second" prefix="milli" exponent="-1"/>
  </units>

  <units name="millivolt">
    <unit units="volt" prefix="milli"/>
  </units>

  <units name="per_millivolt">
    <unit units="volt" prefix="milli" exponent="-1"/>
  </units>
  
  <units name="per_millivolt_millisecond">
    <unit units="millivolt" exponent="-1"/>
    <unit units="millisecond" exponent="-1"/>
  </units>
  
  <units name="milliS_per_mm2">
    <unit units="siemens" prefix="milli"/>
    <unit units="metre" prefix="centi" exponent="-2"/>
  </units>

  <units name="microF_per_mm2">
    <unit units="farad" prefix="micro"/>
    <unit units="metre" prefix="centi" exponent="-2"/>
  </units>

  <units name="microA_per_mm2">
    <unit units="ampere" prefix="micro"/>
    <unit units="metre" prefix="centi" exponent="-2"/>
  </units>
  
  <units name="concentration_units">
    <unit units="mole" prefix="milli"/>
    <unit units="litre" exponent="-1"/>
  </units>
    
  <!--
    The "environment" component is used to declare variables that are used by
    all or most of the other components, in this case just "time".
  -->
  <component name="environment">
    <variable units="millisecond" public_interface="out" name="time"/>
  </component>
  
  <component cmeta:id="membrane" name="membrane">
     
    <variable units="millivolt" public_interface="out" name="V"/>
    
    <variable units="microF_per_mm2" name="C" initial_value="1.3e-2"/>
    
    <variable units="millisecond" public_interface="in" name="time"/>
    <variable units="microA_per_mm2" public_interface="in" name="i_Na"/>
    <variable units="microA_per_mm2" public_interface="in" name="i_s"/>
    <variable units="microA_per_mm2" public_interface="in" name="i_x1"/>
    <variable units="microA_per_mm2" public_interface="in" name="i_K1"/>
    
    <math xmlns="http://www.w3.org/1998/Math/MathML">
      <apply id="membrane_voltage_diff_eq">
        <eq/>
        <apply>
          <diff/>
          <bvar>
            <ci> time </ci>
          </bvar>
          <ci> V </ci>
        </apply>
        <apply>
          <divide/>
          <apply>
            <minus/>
            <apply>
              <plus/>
              <ci> i_Na </ci>
              <ci> i_s </ci>
              <ci> i_x1 </ci>
              <ci> i_K1 </ci>
            </apply>
          </apply>
          <ci> C </ci>
        </apply>
      </apply>
    </math>
  </component>
  
  <component cmeta:id="fast_sodium_current" name="fast_sodium_current">
    
    <variable units="microA_per_mm2" public_interface="out" name="i_Na"/>
    <variable units="milliS_per_mm2" name="g_Na" initial_value="15.0e-2"/>
    <variable units="millivolt" name="E_Na" initial_value="40.0"/>
    <variable units="dimensionless" private_interface="in" name="m"/>
    <variable units="dimensionless" private_interface="in" name="h"/>
    <variable units="millisecond" public_interface="in" private_interface="out" name="time"/>
    <variable units="millivolt" public_interface="in" private_interface="out" name="V"/>
    <math xmlns="http://www.w3.org/1998/Math/MathML">
      <apply id="i_Na_calculation">
        <eq/>
        <ci> i_Na </ci>
        <apply>
          <times/>
          <ci> g_Na </ci>
            <apply>
            <power/>
              <ci> m </ci>
              <cn cellml:units="dimensionless"> 3.0 </cn>
            </apply>
            <ci> h </ci>
            <apply>
            <minus/>
            <ci> V </ci>
            <ci> E_Na </ci>
          </apply>
        </apply>
      </apply>
    </math>
  </component>
  
  <component name="fast_sodium_current_m_gate">
    <variable units="dimensionless" public_interface="out" name="m" initial_value="0.0"/>
    <variable units="per_millisecond" name="alpha_m"/>
    <variable units="per_millisecond" name="beta_m"/>
    <variable units="millivolt" public_interface="in" name="V"/>
    <variable units="millisecond" public_interface="in" name="time"/>
    <math xmlns="http://www.w3.org/1998/Math/MathML">
      <apply id="alpha_m_calculation">
        <eq/>
        <ci> alpha_m </ci>
        <apply>
          <divide/>
          <apply>
            <times/>
            <cn cellml:units="per_millivolt_millisecond"> 0.9 </cn>
            <apply>
              <plus/>
              <ci> V </ci>
              <cn cellml:units="millivolt"> 42.65 </cn>
            </apply>
          </apply>
          <apply>
            <minus/>
            <cn cellml:units="dimensionless"> 1.0 </cn>
            <apply>
              <exp/>
              <apply>
                <times/>
                <cn cellml:units="dimensionless"> -0.22 </cn>
                <apply>
                  <plus/>
                  <ci> V </ci>
                  <cn cellml:units="millivolt"> 42.65 </cn>
                </apply>
              </apply>
            </apply>
          </apply>
        </apply>
      </apply>
      
      <apply id="beta_m_calculation">
        <eq/>
        <ci> beta_m </ci>
        <apply>
          <times/>
          <cn cellml:units="per_millisecond"> 1.437 </cn>
          <apply>
            <exp/>
            <apply>
              <times/>
              <cn cellml:units="dimensionless"> -0.085 </cn>
              <apply>
                <plus/>
                <ci> V </ci>
                <cn cellml:units="millivolt"> 39.75 </cn>
              </apply>
            </apply>
          </apply>
        </apply>
      </apply>
      
      <apply id="dm_dt">
        <eq/>
        <apply>
          <diff/>
          <bvar>
            <ci> time </ci>
          </bvar>
          <ci> m </ci>
        </apply>
        <apply>
          <minus/>
          <apply>
            <times/>
            <ci> alpha_m </ci>
            <apply>
              <minus/>
              <cn cellml:units="per_millivolt"> 1.0 </cn>
              <ci> m </ci>
            </apply>
          </apply>
          <apply>
            <times/>
            <ci> beta_m </ci>
            <ci> m </ci>
          </apply>
        </apply>
      </apply>
    </math>
  </component>
      
  <component name="fast_sodium_current_h_gate">
    <variable units="dimensionless" public_interface="out" name="h" initial_value="0.18"/>
    <variable units="per_millisecond" name="alpha_h"/>
    <variable units="per_millisecond" name="beta_h"/>
    <variable units="millivolt" public_interface="in" name="V"/>
    <variable units="millisecond" public_interface="in" name="time"/>
    <math xmlns="http://www.w3.org/1998/Math/MathML">
      <apply id="alpha_h_calculation">
        <eq/>
        <ci> alpha_h </ci>
        <apply>
          <times/>
          <cn cellml:units="per_millisecond"> 0.1 </cn>
          <apply>
            <exp/>
            <apply>
              <times/>
              <cn cellml:units="dimensionless"> -0.193 </cn>
              <apply>
                <plus/>
                <ci> V </ci>
                <cn cellml:units="millivolt"> 79.65 </cn>
              </apply>
            </apply>
          </apply>
        </apply>
      </apply>
      
      <apply id="beta_h_calculation">
        <eq/>
        <ci> beta_h </ci>
        <apply>
          <divide/>
          <cn cellml:units="dimensionless"> 1.7 </cn>
          <apply>
            <plus/>
            <cn cellml:units="dimensionless"> 1.0 </cn>
            <apply>
              <exp/>
              <apply>
                <times/>
                <cn cellml:units="dimensionless"> -0.095 </cn>
                <apply>
                  <plus/>
                  <ci> V </ci>
                  <cn cellml:units="millivolt"> 20.5 </cn>
                </apply>
              </apply>
            </apply>
          </apply>
        </apply>
      </apply>
      
      <apply id="dh_dt">
        <eq/>
        <apply>
          <diff/>
          <bvar>
            <ci> time </ci>
          </bvar>
          <ci> h </ci>
        </apply>
        <apply>
          <minus/>
          <apply>
            <times/>
            <ci> alpha_h </ci>
            <apply>
              <minus/>
              <cn cellml:units="dimensionless"> 1.0 </cn>
              <ci> h </ci>
            </apply>
          </apply>
          <apply>
            <times/>
            <ci> beta_h </ci>
            <ci> h </ci>
          </apply>
        </apply>
      </apply>
    </math>
  </component>
  
  <component name="slow_inward_current">
    <variable units="microA_per_mm2" public_interface="out" name="i_s"/>
 
    <variable units="milliS_per_mm2" name="g_s" initial_value="9.0e-4"/>
    <variable units="millivolt" name="E_s"/>
    <variable units="concentration_units" name="Cai" initial_value="0.000000177"/>
    
    <variable units="millisecond" public_interface="in" private_interface="out" name="time"/>
    <variable units="millivolt" public_interface="in" private_interface="out" name="V"/>
    
    <variable units="dimensionless" private_interface="in" name="d"/>
    <variable units="dimensionless" private_interface="in" name="f"/>
    
    <math xmlns="http://www.w3.org/1998/Math/MathML">
      <apply id="E_s_calculation">
        <eq/>
        <ci> E_s </ci>
        <apply>
          <minus/>
          <cn cellml:units="millivolt"> -82.3 </cn>
          <apply>
            <times/>
            <cn cellml:units="millivolt"> 13.0287 </cn>
            <apply>
              <ln/>
              <ci> Cai </ci>
            </apply>
          </apply>
        </apply>
      </apply>
      
      <apply id="i_s_calculation">
        <eq/>
        <ci> i_s </ci>
        <apply>
          <times/>
          <ci> g_s </ci>
          <ci> d </ci>
          <ci> f </ci>
          <apply>
            <minus/>
            <ci> V </ci>
            <ci> E_s </ci>
          </apply>
        </apply>
      </apply>
  
      <apply id="dCai_dt">
        <eq/>
        <apply>
          <diff/>
          <bvar>
            <ci> time </ci>
          </bvar>
          <ci> Cai </ci>
        </apply>
        <apply>
          <plus/>
          <apply>
            <times/>
            <cn cellml:units="dimensionless"> -0.001 </cn>
            <ci> i_s </ci>
          </apply>
          <apply>
            <times/>
            <cn cellml:units="dimensionless"> 0.07 </cn>
            <apply>
              <minus/>
              <cn cellml:units="dimensionless"> -0.001 </cn>
              <ci> Cai </ci>
            </apply>
          </apply>
        </apply>
      </apply>
    </math>
  </component>
          
  <component name="slow_inward_current_d_gate">
    <variable units="dimensionless" public_interface="out" name="d" initial_value="0.003"/>

    <variable units="per_millisecond" name="alpha_d"/>
    <variable units="per_millisecond" name="beta_d"/>
    
    <variable units="millivolt" public_interface="in" name="V"/>
    <variable units="millisecond" public_interface="in" name="time"/>

    <math xmlns="http://www.w3.org/1998/Math/MathML">
      <apply id="alpha_d_calculation">
        <eq/>
        <ci> alpha_d </ci>
        <apply>
          <divide/>
          <apply>
            <times/>
            <cn cellml:units="per_millisecond"> 0.095 </cn>
            <apply>
              <exp/>
              <apply>
                <minus/>
                <apply>
                  <divide/>
                  <apply>
                    <plus/>
                    <ci> V </ci>
                    <cn cellml:units="millivolt"> -5.0 </cn>
                  </apply>
                  <cn cellml:units="millivolt"> 100.0 </cn>
                </apply>
              </apply>
            </apply>
          </apply>
          <apply>
            <plus/>
            <cn cellml:units="dimensionless"> 1.0 </cn>
            <apply>
              <exp/>
              <apply>
                <minus/>
                <apply>
                  <divide/>
                  <apply>
                    <plus/>
                    <ci> V </ci>
                    <cn cellml:units="millivolt"> -5.0 </cn>
                  </apply>
                  <cn cellml:units="millivolt"> 13.89 </cn>
                </apply>
              </apply>
            </apply>
          </apply>
        </apply>
      </apply>
      
      <apply id="beta_d_calculation">
        <eq/>
        <ci> beta_d </ci>
        <apply>
          <divide/>
          <apply>
            <times/>
            <cn cellml:units="per_millisecond"> 0.07 </cn>
            <apply>
              <exp/>
              <apply>
                <minus/>
                <apply>
                  <divide/>
                  <apply>
                    <plus/>
                    <ci> V </ci>
                    <cn cellml:units="millivolt"> 44.0 </cn>
                  </apply>
                  <cn cellml:units="millivolt"> 59.0 </cn>
                </apply>
              </apply>
            </apply>
          </apply>
          <apply>
            <plus/>
            <cn cellml:units="dimensionless"> 1.0 </cn>
            <apply>
              <exp/>
              <apply>
                <divide/>
                <apply>
                  <plus/>
                  <ci> V </ci>
                  <cn cellml:units="millivolt"> 44.0 </cn>
                </apply>
                <cn cellml:units="millivolt"> 20.0 </cn>
              </apply>
            </apply>
          </apply>
        </apply>
      </apply>
          
      <apply id="dd_dt">
        <eq/>
        <apply>
          <diff/>
          <bvar>
            <ci> time </ci>
          </bvar>
          <ci> d </ci>
        </apply>
        <apply>
          <minus/>
          <apply>
            <times/>
            <ci> alpha_d </ci>
            <apply>
              <minus/>
              <cn cellml:units="dimensionless"> 1.0 </cn>
              <ci> d </ci>
            </apply>
          </apply>
          <apply>
            <times/>
            <ci> beta_d </ci>
            <ci> d </ci>
          </apply>
        </apply>
      </apply>
    </math>
  </component>
  
  <component name="slow_inward_current_f_gate">
    <variable units="dimensionless" public_interface="out" name="f" initial_value="0.994"/> 

    <variable units="per_millisecond" name="alpha_f"/>
    <variable units="per_millisecond" name="beta_f"/>
    
    <variable units="millivolt" public_interface="in" name="V"/>
    <variable units="millisecond" public_interface="in" name="time"/>
     
     
    <math xmlns="http://www.w3.org/1998/Math/MathML">
      <apply id="alpha_f_calculation">
        <eq/>
        <ci> alpha_f </ci>
        <apply>
          <divide/>
          <apply>
            <times/>
          <cn cellml:units="per_millisecond"> 0.012 </cn>
          <apply>
              <exp/>
            <apply>
                <minus/>
              <apply>
                  <divide/>
                <apply>
                    <plus/>
                  <ci> V </ci>
                  <cn cellml:units="millivolt"> 28.0 </cn>
                </apply>
                <cn cellml:units="millivolt"> 125.0 </cn>
              </apply>
            </apply>
          </apply>
        </apply>
        <apply>
            <plus/>
          <cn cellml:units="dimensionless"> 1.0 </cn>
          <apply>
              <exp/>
            <apply>
                <divide/>
              <apply>
                  <plus/>
                <ci> V </ci>
                <cn cellml:units="millivolt"> 28.0 </cn>
              </apply>
              <cn cellml:units="millivolt"> 6.67 </cn>
            </apply>
          </apply>
        </apply>
      </apply>
    </apply>
         
    <apply id="beta_f_calculation">
        <eq/>
      <ci> beta_f </ci>
      <apply>
          <divide/>
        <apply>
            <times/>
          <cn cellml:units="per_millisecond"> 0.0065 </cn>
          <apply>
              <exp/>
            <apply>
                <minus/>
              <apply>
                  <divide/>
                <apply>
                    <plus/>
                  <ci> V </ci>
                  <cn cellml:units="millivolt"> 30.0 </cn>
                </apply>
                <cn cellml:units="millivolt"> 50.0 </cn>
              </apply>
            </apply>
          </apply>
        </apply>
        <apply>
            <plus/>
          <cn cellml:units="dimensionless"> 1.0 </cn>
            <apply>
              <exp/>
              <apply>
                <minus/>
                <apply>
                  <divide/>
                  <apply>
                    <plus/>
                    <ci> V </ci>
                    <cn cellml:units="millivolt"> 30.0 </cn>
                  </apply>
                  <cn cellml:units="millivolt"> 5.0 </cn>
                </apply>
              </apply>
            </apply>
          </apply>
        </apply>
      </apply>
         
      <apply id="df_dt">
        <eq/>
        <apply>
          <diff/>
          <bvar>
            <ci> time </ci>
          </bvar>
          <ci> f </ci>
        </apply>
        <apply>
          <minus/>
          <apply>
            <times/>
            <ci> alpha_f </ci>
             <apply>
              <minus/>
              <cn cellml:units="dimensionless"> 1.0 </cn>
              <ci> f </ci>
            </apply>
          </apply>
          <apply>
            <times/>
            <ci> beta_f </ci>
            <ci> f </ci>
          </apply>
        </apply>
      </apply>
    </math>
  </component>
    
  
  <component name="time_dependent_outward_current">
    <variable units="microA_per_mm2" public_interface="out" name="i_x1"/>
    
    <variable units="per_millisecond" name="alpha_x1"/>
    <variable units="per_millisecond" name="beta_x1"/>
    
    <variable units="millisecond" public_interface="in" private_interface="out" name="time"/>
    <variable units="millivolt" public_interface="in" private_interface="out" name="V"/>
     
    <variable units="dimensionless" private_interface="in" name="x1"/>
        
    <math xmlns="http://www.w3.org/1998/Math/MathML">
      <apply id="i_x1_calculation">
        <eq/>
        <ci> i_x1 </ci>
        <apply>
          <times/>
          <ci> x1 </ci>
          <cn cellml:units="dimensionless"> 0.8 </cn>
          <apply>
            <divide/>
            <apply>
              <minus/>
              <apply>
                <exp/>
                <apply>
                  <times/>
                  <cn cellml:units="per_millivolt"> 0.04 </cn>
                  <apply>
                    <plus/>
                    <ci> V </ci>
                    <cn cellml:units="millivolt"> 77.0 </cn>
                  </apply>
                </apply>
              </apply>
              <cn cellml:units="dimensionless"> 1.0 </cn>
            </apply>
            <apply>
              <exp/>
              <apply>
                <times/>
                <cn cellml:units="per_millivolt"> 0.04 </cn>
                <apply>
                  <plus/> 
                  <ci> V </ci>
                  <cn cellml:units="millivolt"> 35.0 </cn>
                </apply>
              </apply>
            </apply>
          </apply>
        </apply>
      </apply>
    </math>
  </component>
  
  <component name="time_dependent_outward_current_x1_gate">
    <variable units="dimensionless" public_interface="out" name="x1"/>
    <variable units="per_millisecond" name="alpha_x1"/>
    <variable units="per_millisecond" name="beta_x1"/>
    <variable units="millivolt" public_interface="in" name="V"/>
    <variable units="millisecond" public_interface="in" name="time"/>
    
    <math xmlns="http://www.w3.org/1998/Math/MathML">        
      <apply id="alpha_x1_calculation">
        <eq/>
        <ci> alpha_x1 </ci>
        <apply>
          <times/>
          <cn cellml:units="per_millisecond"> 5e-4 </cn>
          <apply>
            <divide/>
            <apply>
              <exp/>
              <apply>
                <divide/>
                <apply>
                  <plus/>
                  <ci> V </ci>
                  <cn cellml:units="millivolt"> 50.0 </cn>                      
                </apply>
                <cn cellml:units="millivolt"> 12.1 </cn>
              </apply>
            </apply>
            <apply>
              <plus/>
              <cn cellml:units="dimensionless"> 1.0 </cn>
              <apply>
                <exp/>
                <apply>
                  <divide/>
                  <apply>
                    <plus/>
                    <ci> V </ci>
                    <cn cellml:units="millivolt"> 50.0 </cn>
                  </apply>
                  <cn cellml:units="millivolt"> 17.5 </cn>
                </apply>
              </apply>
            </apply>
          </apply>
        </apply>
      </apply>
         
      <apply id="beta_x1_calculation">
        <eq/>
        <ci> beta_x1 </ci>
        <apply>
          <times/>
          <cn cellml:units="per_millisecond"> 0.0013 </cn>
          <apply>
            <divide/>
            <apply>
              <exp/>
              <apply>
                <minus/>
                <apply>
                  <divide/>
                  <apply>
                    <plus/>
                    <ci> V </ci>                                                
                    <cn cellml:units="millivolt"> 20.0 </cn>
                  </apply>
                  <cn cellml:units="millivolt"> 16.67 </cn>
                </apply>
              </apply>
            </apply>
            <apply>
              <plus/>
              <cn cellml:units="dimensionless"> 1.0 </cn>
              <apply>
                <exp/>
                <apply>
                  <minus/>
                  <apply>
                    <divide/>
                    <apply>
                      <plus/>
                      <ci> V </ci>
                      <cn cellml:units="millivolt"> 20.0 </cn>
                    </apply>
                    <cn cellml:units="millivolt"> 25.0 </cn>
                  </apply> 
                </apply>
              </apply>
            </apply>
          </apply>
        </apply>
      </apply>
      
      <apply id="dx1_dt">
        <eq/>
        <apply>
          <diff/>
          <bvar>
            <ci> time </ci>
          </bvar>
          <ci> x1 </ci>
        </apply>
        <apply>
          <minus/>
          <apply>
            <times/>
            <ci> alpha_x1 </ci>
            <apply>
              <minus/>
              <cn cellml:units="dimensionless"> 1.0 </cn>
              <ci> x1 </ci>
            </apply>
          </apply>
          <apply>
            <times/>
            <ci> beta_x1 </ci>
            <ci> x1 </ci>
          </apply>
        </apply>
      </apply>
    </math>
  </component>
     
  
  <component name="time_independent_outward_current">
    <variable units="microA_per_mm2" public_interface="out" name="i_K1"/>
    
    <variable units="millisecond" public_interface="in" name="time"/>
    <variable units="millivolt" public_interface="in" name="V"/>
        
    <math xmlns="http://www.w3.org/1998/Math/MathML">
      <apply id="i_K1_calculation">
        <eq/>
        <ci> i_K1 </ci>
        <apply>
          <times/>
          <cn cellml:units="dimensionless"> 0.35 </cn>
          <apply>
            <plus/>
            <apply>
              <times/>
              <cn cellml:units="per_millisecond"> 4.0 </cn>
              <apply>
                <divide/>
                <apply>
                  <minus/>
                  <apply>
                    <exp/>
                    <apply>
                      <times/>
                      <cn cellml:units="per_millivolt"> 0.04 </cn>
                      <apply>
                        <plus/>
                        <ci> V </ci>
                        <cn cellml:units="millivolt"> 85.0 </cn>
                      </apply>
                    </apply>                   
                  </apply>
                  <cn cellml:units="dimensionless"> 1.0 </cn>
                </apply>
                <apply>
                  <plus/>
                  <apply>
                    <exp/>
                    <apply>
                      <times/>
                      <cn cellml:units="per_millivolt"> 0.08 </cn>
                      <apply>
                        <plus/>
                        <ci> V </ci>
                        <cn cellml:units="millivolt"> 53 </cn>
                      </apply>
                    </apply>
                  </apply>
                  <apply>
                    <exp/>
                    <apply>
                      <times/> 
                      <cn cellml:units="per_millivolt"> 0.04 </cn>
                      <apply>
                        <plus/>
                        <ci> V </ci>
                        <cn cellml:units="millivolt"> 53.0 </cn>
                      </apply>
                    </apply>          
                  </apply>
                </apply>
              </apply>
            </apply>
            <apply>
              <times/>
              <cn cellml:units="per_millisecond"> 0.2 </cn>
              <apply>
                <divide/>
                <apply>
                  <plus/>
                  <ci> V </ci>
                  <cn cellml:units="millivolt"> 23.0 </cn>
                </apply>
                <apply>
                  <minus/>
                  <cn cellml:units="dimensionless"> 1.0 </cn>
                  <apply>
                    <exp/>
                    <apply>
                      <times/>
                      <cn cellml:units="per_millivolt"> -0.04 </cn>
                      <apply>
                        <plus/>
                        <ci> V </ci>
                        <cn cellml:units="millivolt"> 23.0 </cn>
                      </apply>
                    </apply>
                  </apply>
                </apply>
              </apply>
            </apply>
          </apply>
        </apply>
      </apply>
    </math>
  </component>
   
  
  <group>
    <relationship_ref relationship="containment"/>
    <component_ref component="membrane">
      <component_ref component="fast_sodium_current">
        <component_ref component="fast_sodium_current_m_gate"/>
        <component_ref component="fast_sodium_current_h_gate"/>
      </component_ref>
      <component_ref component="slow_inward_current">
        <component_ref component="slow_inward_current_d_gate"/>
        <component_ref component="slow_inward_current_f_gate"/>
      </component_ref>
      <component_ref component="time_dependent_outward_current">
        <component_ref component="time_dependent_outward_current_x1_gate"/>
      </component_ref>
      <component_ref component="time_independent_outward_current"/>
    </component_ref>
  </group>


  <group>
    <relationship_ref relationship="encapsulation"/>
    <component_ref component="fast_sodium_current">
      <component_ref component="fast_sodium_current_m_gate"/>
      <component_ref component="fast_sodium_current_h_gate"/>
    </component_ref>
    <component_ref component="slow_inward_current">
      <component_ref component="slow_inward_current_d_gate"/>
      <component_ref component="slow_inward_current_f_gate"/>
    </component_ref>
    <component_ref component="time_dependent_outward_current">
      <component_ref component="time_dependent_outward_current_x1_gate"/>
    </component_ref>
  </group>
  
  <connection>
    <map_components component_2="environment" component_1="membrane"/>
    <map_variables variable_2="time" variable_1="time"/>
  </connection>
  
  <connection>
    <map_components component_2="environment" component_1="fast_sodium_current"/>
    <map_variables variable_2="time" variable_1="time"/>
  </connection>
  
  <connection>
    <map_components component_2="environment" component_1="slow_inward_current"/>
    <map_variables variable_2="time" variable_1="time"/>
  </connection>

  <connection>
    <map_components component_2="environment" component_1="time_dependent_outward_current"/>
    <map_variables variable_2="time" variable_1="time"/>
  </connection>
   
  <connection>
    <map_components component_2="environment" component_1="time_independent_outward_current"/>
    <map_variables variable_2="time" variable_1="time"/>
  </connection>
  
  <connection>
    <map_components component_2="fast_sodium_current" component_1="membrane"/>
    <map_variables variable_2="V" variable_1="V"/>
     <map_variables variable_2="i_Na" variable_1="i_Na"/>
  </connection>

  <connection>
    <map_components component_2="slow_inward_current" component_1="membrane"/>
    <map_variables variable_2="V" variable_1="V"/>
    <map_variables variable_2="i_s" variable_1="i_s"/>
  </connection>

  <connection>
    <map_components component_2="time_dependent_outward_current" component_1="membrane"/>
    <map_variables variable_2="V" variable_1="V"/>
    <map_variables variable_2="i_x1" variable_1="i_x1"/>
  </connection>
  
  <connection>
    <map_components component_2="time_independent_outward_current" component_1="membrane"/>
    <map_variables variable_2="V" variable_1="V"/>
    <map_variables variable_2="i_K1" variable_1="i_K1"/>
  </connection>
  
  <connection>
    <map_components component_2="fast_sodium_current_m_gate" component_1="fast_sodium_current"/>
    <map_variables variable_2="m" variable_1="m"/>
    <map_variables variable_2="time" variable_1="time"/>
    <map_variables variable_2="V" variable_1="V"/>
  </connection>

  <connection>
    <map_components component_2="fast_sodium_current_h_gate" component_1="fast_sodium_current"/>
    <map_variables variable_2="h" variable_1="h"/>
    <map_variables variable_2="time" variable_1="time"/>
    <map_variables variable_2="V" variable_1="V"/>
  </connection>
  
  <connection>
    <map_components component_2="time_dependent_outward_current_x1_gate" component_1="time_dependent_outward_current"/>
    <map_variables variable_2="x1" variable_1="x1"/>
    <map_variables variable_2="time" variable_1="time"/>
    <map_variables variable_2="V" variable_1="V"/>
  </connection>
  
  <connection>
    <map_components component_2="slow_inward_current_d_gate" component_1="slow_inward_current"/>
    <map_variables variable_2="d" variable_1="d"/>
    <map_variables variable_2="time" variable_1="time"/>
    <map_variables variable_2="V" variable_1="V"/>
  </connection>
  
  <connection>
    <map_components component_2="slow_inward_current_f_gate" component_1="slow_inward_current"/>
    <map_variables variable_2="f" variable_1="f"/>
    <map_variables variable_2="time" variable_1="time"/>
    <map_variables variable_2="V" variable_1="V"/>
  </connection>





<rdf:RDF>
  <rdf:Bag rdf:about="rdf:#0d3890db-bbc3-4940-9bb2-4dfb7c810c97">
    <rdf:li>Ventricular Myocyte</rdf:li>
    <rdf:li>cardiac</rdf:li>
    <rdf:li>electrophysiology</rdf:li>
  </rdf:Bag>
  <rdf:Seq rdf:about="rdf:#citationAuthorsSeq">
    <rdf:li rdf:resource="rdf:#author1Vcard"/>
    <rdf:li rdf:resource="rdf:#author2Vcard"/>
  </rdf:Seq>
  <rdf:Description rdf:about="rdf:#b943afd9-50fb-4857-a8f6-c6d9dd87aef8">
    <dcterms:W3CDTF>2001-12-17</dcterms:W3CDTF>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#83c6d257-00f8-4b32-86d3-c1ddda4efbe5">
    <vCard:Given>Catherine</vCard:Given>
    <vCard:Family>Lloyd</vCard:Family>
    <vCard:Other>May</vCard:Other>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#e7f26808-d18c-4aa8-bfd4-89ef00ce9f55">
    <rdf:type rdf:resource="http://purl.org/dc/terms/W3CDTF"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#7fe82554-2abc-4f1d-a19a-fff8811faa6f">
    <dcterms:modified rdf:resource="rdf:#d31a8955-1b1a-46e1-9b43-cd66039ec27f"/>
    <rdf:value>
          Added more metadata.
        </rdf:value>
    <cmeta:modifier rdf:resource="rdf:#51be86d6-5f7b-43f6-89f1-54035aaec4a2"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#6e63e024-03a0-4193-b3c2-67c0eccea50f">
    <vCard:N rdf:resource="rdf:#83c6d257-00f8-4b32-86d3-c1ddda4efbe5"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#0bb62487-2463-482b-b7e9-b1038a0c2b14">
    <dcterms:W3CDTF>2003-04-09</dcterms:W3CDTF>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#eed3cafd-5432-4d83-b39a-362ca18eccce">
    <rdf:type rdf:resource="http://purl.org/dc/terms/W3CDTF"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#author2VcardN">
    <vCard:Given>F</vCard:Given>
    <vCard:Family>Roberge</vCard:Family>
    <vCard:Other>A</vCard:Other>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#6e588520-6c39-4937-9011-d127f9e9c8a4">
    <dcterms:modified rdf:resource="rdf:#e7f26808-d18c-4aa8-bfd4-89ef00ce9f55"/>
    <rdf:value>
          Updated metadata to conform to the 16/1/02 CellML Metadata 1.0 
          Specification.
        </rdf:value>
    <cmeta:modifier rdf:resource="rdf:#701a6272-3302-4bb4-9926-f6cc4358c2a4"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#298549da-6fd2-401d-98bb-5464ed041b3e">
    <rdf:type rdf:resource="http://www.w3.org/2001/vcard-rdf/3.0#N"/>
    <vCard:Given>Catherine</vCard:Given>
    <vCard:Family>Lloyd</vCard:Family>
    <vCard:Other>May</vCard:Other>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#51b8bbc2-2d4d-4321-a1f0-8a29f8fe1e0d">
    <vCard:Given>Autumn</vCard:Given>
    <vCard:Family>Cuellar</vCard:Family>
    <vCard:Other>A</vCard:Other>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#author2Vcard">
    <rdf:type rdf:resource="http://www.cellml.org/bqs/1.0#Person"/>
    <vCard:N rdf:resource="rdf:#author2VcardN"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#51be86d6-5f7b-43f6-89f1-54035aaec4a2">
    <vCard:N rdf:resource="rdf:#002468d4-5751-465e-b256-cd8fe48688a3"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#3fc5cd2b-563e-4999-ba21-1b69f0972140">
    <rdf:value>
            The Drouhard-Roberge model uses the Hodgkin-Huxley formulation for 
            the sodium membrane current with only one inactivation variable (h) 
            rather than the two (h and j) of the Beeler-Reuter model.  At the 
            time of the study (1987) there was still much uncertainty regarding 
            the existence and function of the j gate.
          </rdf:value>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#058dddd0-68c7-4089-8c83-84ed7eb8cbfa">
    <dcterms:modified rdf:resource="rdf:#0bb62487-2463-482b-b7e9-b1038a0c2b14"/>
    <rdf:value>
          Added publication date information.
        </rdf:value>
    <cmeta:modifier rdf:resource="rdf:#141bae38-afc9-4e9f-8c26-3315ccde265a"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#12796d5b-ef73-491d-8fdd-01e50384eedf">
    <vCard:ORG rdf:resource="rdf:#025e564a-7fc0-41d4-adab-8f469ecaf357"/>
    <vCard:EMAIL rdf:resource="rdf:#11e022ad-a283-429e-b41f-24e057b90a38"/>
    <vCard:N rdf:resource="rdf:#821bce9a-119a-465c-b2d7-58c91e7de10c"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#d31a8955-1b1a-46e1-9b43-cd66039ec27f">
    <dcterms:W3CDTF>2002-07-19</dcterms:W3CDTF>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#ba916c43-5790-41f2-a561-d59a53702e54">
    <dcterms:W3CDTF>1987-08-01</dcterms:W3CDTF>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#fdbe4340-9578-4a62-aad7-53543ba4b386">
    <dcterms:modified rdf:resource="rdf:#94c14439-1bb2-422a-be1b-4c7b79d0a5f6"/>
    <rdf:value>
          Added the components of the Beeler-Reuter Model.
        </rdf:value>
    <cmeta:modifier rdf:resource="rdf:#8ec405f8-3986-4d73-ac07-d3dfebe6ef95"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#c4f5252d-50c5-4231-abfd-f7ce02e72c26">
    <dcterms:modified rdf:resource="rdf:#43b07604-1895-40b4-b0eb-e06f74d033dc"/>
    <rdf:value>
          Changed equations.
        </rdf:value>
    <cmeta:modifier rdf:resource="rdf:#6e63e024-03a0-4193-b3c2-67c0eccea50f"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#8ec405f8-3986-4d73-ac07-d3dfebe6ef95">
    <rdf:type rdf:resource="http://www.w3.org/2001/vcard-rdf/3.0#N"/>
    <vCard:Given>Catherine</vCard:Given>
    <vCard:Family>Lloyd</vCard:Family>
    <vCard:Other>May</vCard:Other>
  </rdf:Description>
  <rdf:Description rdf:about="#fast_sodium_current">
    <cmeta:comment rdf:resource="rdf:#3fc5cd2b-563e-4999-ba21-1b69f0972140"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#c23f2098-7d56-4af2-853b-2274c3f1cb8f">
    <bqs:Pubmed_id>3621918</bqs:Pubmed_id>
    <bqs:JournalArticle rdf:resource="rdf:#d65158a3-c8c2-4120-a885-8d0823f1fcb1"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#15cb1cff-3458-4c46-aa30-0fcf556ce16a">
    <dc:title>Computers and Biomedical Research</dc:title>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#2f57121c-edaf-440e-99a4-6f1cf0643430">
    <dc:subject rdf:resource="rdf:#73d2a8d6-011d-498d-b74e-f21d3b968442"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#025e564a-7fc0-41d4-adab-8f469ecaf357">
    <vCard:Orgname>The University of Auckland</vCard:Orgname>
    <vCard:Orgunit>The Bioengineering Research Group</vCard:Orgunit>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#cd096cc7-b1b5-411c-9864-a5ff3714f910">
    <vCard:FN>Catherine Lloyd</vCard:FN>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#94c14439-1bb2-422a-be1b-4c7b79d0a5f6">
    <rdf:type rdf:resource="http://purl.org/dc/terms/W3CDTF"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#141bae38-afc9-4e9f-8c26-3315ccde265a">
    <vCard:N rdf:resource="rdf:#51b8bbc2-2d4d-4321-a1f0-8a29f8fe1e0d"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#11e022ad-a283-429e-b41f-24e057b90a38">
    <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="#membrane">
    <cmeta:comment rdf:resource="rdf:#5ed6fddf-63cb-4b2d-afe5-aeb10355ad77"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#d65158a3-c8c2-4120-a885-8d0823f1fcb1">
    <dc:creator rdf:resource="rdf:#citationAuthorsSeq"/>
    <dc:title>Revised formulation of the Hodgkin-Huxley representation of the sodium current in cardiac cells</dc:title>
    <bqs:volume>20</bqs:volume>
    <bqs:first_page>333</bqs:first_page>
    <bqs:Journal rdf:resource="rdf:#15cb1cff-3458-4c46-aa30-0fcf556ce16a"/>
    <dcterms:issued rdf:resource="rdf:#ba916c43-5790-41f2-a561-d59a53702e54"/>
    <bqs:last_page>350</bqs:last_page>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#author1VcardN">
    <vCard:Given>J</vCard:Given>
    <vCard:Family>Drouhard</vCard:Family>
    <vCard:Other>P</vCard:Other>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#ea748501-2c60-446c-878a-43c53f109fdd">
    <dc:creator rdf:resource="rdf:#cd096cc7-b1b5-411c-9864-a5ff3714f910"/>
    <rdf:value>This is the CellML description of Drouhard and Roberge's mathematical model of the fast sodium current in ventricular myocardial cells. It describes the ionic current with Hodgkin-Huxley formalism, but revises the original parameters of the equation.</rdf:value>
  </rdf:Description>
  <rdf:Description rdf:about="">
    <dc:publisher>
        The University of Auckland, Bioengineering Research Group
      </dc:publisher>
    <cmeta:modification rdf:resource="rdf:#058dddd0-68c7-4089-8c83-84ed7eb8cbfa"/>
    <cmeta:modification rdf:resource="rdf:#6e588520-6c39-4937-9011-d127f9e9c8a4"/>
    <cmeta:modification rdf:resource="rdf:#7fe82554-2abc-4f1d-a19a-fff8811faa6f"/>
    <cmeta:modification rdf:resource="rdf:#88f3f1a6-337c-4575-baee-e38cec8dbb02"/>
    <cmeta:modification rdf:resource="rdf:#c4f5252d-50c5-4231-abfd-f7ce02e72c26"/>
    <cmeta:modification rdf:resource="rdf:#fdbe4340-9578-4a62-aad7-53543ba4b386"/>
    <dcterms:created rdf:resource="rdf:#b943afd9-50fb-4857-a8f6-c6d9dd87aef8"/>
    <dc:creator rdf:resource="rdf:#12796d5b-ef73-491d-8fdd-01e50384eedf"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#author1Vcard">
    <rdf:type rdf:resource="http://www.cellml.org/bqs/1.0#Person"/>
    <vCard:N rdf:resource="rdf:#author1VcardN"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#88f3f1a6-337c-4575-baee-e38cec8dbb02">
    <dcterms:modified rdf:resource="rdf:#eed3cafd-5432-4d83-b39a-362ca18eccce"/>
    <rdf:value>
          Corrected the membrane voltage differential equation.
        </rdf:value>
    <cmeta:modifier rdf:resource="rdf:#298549da-6fd2-401d-98bb-5464ed041b3e"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#002468d4-5751-465e-b256-cd8fe48688a3">
    <vCard:Given>Catherine</vCard:Given>
    <vCard:Family>Lloyd</vCard:Family>
    <vCard:Other>May</vCard:Other>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#73d2a8d6-011d-498d-b74e-f21d3b968442">
    <bqs:subject_type>keyword</bqs:subject_type>
    <rdf:value rdf:resource="rdf:#0d3890db-bbc3-4940-9bb2-4dfb7c810c97"/>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#5ed6fddf-63cb-4b2d-afe5-aeb10355ad77">
    <rdf:value>
             Like the Ebihara-Johnson model (1980), the Drouhard-Roberge model 
             can be used as a direct replacement for the sodium kinetics of the 
             Beeler-Reuter model.  The other ionic equations and membrane 
             potential are quoted from the original 1977 paper.
           </rdf:value>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#701a6272-3302-4bb4-9926-f6cc4358c2a4">
    <rdf:type rdf:resource="http://www.w3.org/2001/vcard-rdf/3.0#N"/>
    <vCard:Given>Autumn</vCard:Given>
    <vCard:Family>Cuellar</vCard:Family>
    <vCard:Other>A.</vCard:Other>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#43b07604-1895-40b4-b0eb-e06f74d033dc">
    <dcterms:W3CDTF>2003-07-23</dcterms:W3CDTF>
  </rdf:Description>
  <rdf:Description rdf:about="rdf:#821bce9a-119a-465c-b2d7-58c91e7de10c">
    <vCard:Given>Catherine</vCard:Given>
    <vCard:Family>Lloyd</vCard:Family>
    <vCard:Other>May</vCard:Other>
  </rdf:Description>
  <rdf:Description rdf:about="#drouhard_roberge_1987_version01">
    <dc:title>
        The Drouhard-Roberge Model of the Fast Sodium Current in Ventricular 
        Myocardial Cells
      </dc:title>
    <cmeta:bio_entity>Ventricular Myocyte</cmeta:bio_entity>
    <cmeta:comment rdf:resource="rdf:#ea748501-2c60-446c-878a-43c53f109fdd"/>
    <bqs:reference rdf:resource="rdf:#2f57121c-edaf-440e-99a4-6f1cf0643430"/>
    <bqs:reference rdf:resource="rdf:#c23f2098-7d56-4af2-853b-2274c3f1cb8f"/>
    <cmeta:species>Mammalia</cmeta:species>
  </rdf:Description>
</rdf:RDF>
</model>