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Table 4 Parameters used to model intracellular ion transport

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

Parameter Definition Value References
k 12 P L B rate of PLB dp phosphorylation 6800 s-1 [77]*
k 21 P L B rate of PLB p dephosphorylation 1000 s-1 [77]*
K cyt,serca Maximal binding/release rate of Ca2+ from cytosol to SERCA 6250 s-1 [77]*
K serca,sr Maximal binding/release rate of Ca2+ from SERCA to LSR 6.25 s-1 [77]*
SERCA tot Total amount of SERCA 47.0 μM [77]*
PSR Phospholamban to SERCA ratio 1.0 [77]*
PKA ac t Relative regulatory activity of PKA 0.1 [77]
τ tr Time const. for transfer of Ca2+ from LSR to jSR 7.0 × 10-3 s [30]
τ Na Time const. for transfer of Na+ from dyad to myoplasm 1.0 × 10-3 s [30]
τ Cs Time const. for transfer of Cs+ from dyad to myoplasm 6.0 × 10-3 s [30]
P ryr Permeability of the RyR channel 1.714 × 10-7 μL · s-1 [27, 28, 13]
D Ca Diffusion constant for Ca2+ in the dyadic space 100.0 μm2s-1 [119]*
N h Density of high-affinity Ca2+ binding sites 200.0 μM [119]
N l Density of low-affinity Ca2+ binding sites 16.0 μM [119]
K l Half-saturation value of low-affinity Ca2+ binding site 1100.0 μM [119]*
K h Half-saturation value of high-affinity Ca2+ binding site 13.0 μM [119]*
[Mg2+] myo Intracellular Mg2+ concentration 634 μM [124]*
[fluo 3] tot total concentration of indicator dye 100.0 μM Measured
k f l u o 3 + association rate of Ca2+ binding to dye fluo-3 80 μM -1 · s-1 [125]*
k f l u o 3 dissociation rate of Ca2+ binding to dye fluo-3 90 s-1 [125]*
  1. Table 4 Parameters used to model the intracellular ion transport I cyt,serca , I serca.sr , I tr , I RyR , and Ca2+ diffusion/buffering. Adopted (*), derived (†) or estimated (‡) from the cited sources.