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Table 3 Parameters used to model ion transport across the sarcolemmal membrane

From: Modeling CICR in rat ventricular myocytes: voltage clamp studies

Parameter Definition Value References
F Faraday's constant 96485 coul · mol-1 --
R Ideal gas constant 8314 mJ · mol-1 · K-1 --
T Absolute temperature 290 K Measured
[Ca2+] o Extracellular Ca2+ concentration 1.0 mM Measured
[Na+] o Extracellular Na+ concentration 140.0 mM Measured
[Cs+] o Extracellular Cs+ concentration 3.0 mM Measured
Z Na , Z Cs Valence of Na+ and Cs+ ions 1.0 --
Z Ca , Z Ba Valence of Ca2+ and Ba2+ ions 2.0 --
P Ca Permeability of L-Type calcium channel to Ca2+ 6.7367 × 10-9 μL · s-1 [30]*
P Na Permeability of L-Type calcium channel to Na+ 8.0355 × 10-11 μL · s-1 [30]*
P Cs Permeability of L-Type calcium channel to Cs+ 6.2088 × 10-11 μL · s-1 [30]*
K mAllo Dissociation constant for allosteric Ca2+ activation 125 × 10-6 mM [85]*
K mCao Dissociation constant for extracellular Ca2+ 1.14 mM [85]*
K mCai Dissociation constant for intracellular Ca2+ 0.0036 mM [122]*
K mNao Dissociation constant for extracellular Na+ 87.5 mM [83]*
K mNai Dissociation constant for intracellular Na+ 12.3 mM [85]*
V max Maximum Na+/Ca+ exchange current 776.2392 pA [85]*
k mpca Half saturation constant for the SL Ca2+ pump 0.5 μM [30]*
I ¯ P M C A Maximum sarcolemmal Ca2+ pump current 1.15 pA [30]*
K mcs Dissociation constant for extracellular Cs+ 1.5 × 103 μM [94, 92, 88, 74]
K mna Dissociation constant for intracellular Na+ 2.14 × 105 μM [94, 92, 88, 74]
I ¯ N a C s Maximum Na+/Cs+ pump current 147.3 pA [94, 92, 88, 74]
G Nab Maximum background Na+ current conductance 0.00141 nS [30]*
R a Mean access resistance of the tubular system 20.0 [123]*
  1. Table 3: Parameters used to model the transmembrane currents ICa,L, I NaCa , I PMCA , I NaCs and the background sodium current I Na,b . Adopted (*) or estimated (‡) from the cited sources.