Table 3. Release flux calculation... | Rockefeller University Press

Table 3.

Release flux calculation

Binding site	Concentration	k_ON	k_OFF	Diffusion coefficient	Flux
	µM	(µM ms)⁻¹	ms⁻¹	µm² ms⁻¹	mM/s
ATP	5,000	Ca, 0.15	30	0.14	25.3
		Mg, 2e-3	0.2
EGTA	350	4e-3	2e-3	0.07	0.6
Fluo-4	40	0.032	0.032	0.05	1.4
SERCA	47	0.5	0.5	N.A.	0.9
Troponin	70	5.7e-3	0.011	N.A.	0.1
Sarcolemma	42	0.1	1.3	N.A.	0.1
Free Ca²⁺*	variable	N.A.	N.A.	0.35	24.7

Binding site	Concentration	k_ON	k_OFF	Diffusion coefficient	Flux
	µM	(µM ms)⁻¹	ms⁻¹	µm² ms⁻¹	mM/s
ATP	5,000	Ca, 0.15	30	0.14	25.3
		Mg, 2e-3	0.2
EGTA	350	4e-3	2e-3	0.07	0.6
Fluo-4	40	0.032	0.032	0.05	1.4
SERCA	47	0.5	0.5	N.A.	0.9
Troponin	70	5.7e-3	0.011	N.A.	0.1
Sarcolemma	42	0.1	1.3	N.A.	0.1
Free Ca²⁺*	variable	N.A.	N.A.	0.35	24.7

Model parameters (concentration, reaction rates, and diffusion coefficients) are given for all Ca²⁺ ligands used in the calculation. The last column lists maximal contributions to the flux total by the binding of Ca²⁺ to the corresponding ligand. The last row lists the free Ca²⁺ term in the flux calculation (namely, the flux required to account for the local rate of change of [Ca²⁺] and diffusion of the free ion). With minor changes, parameters are as in Santiago et al. (2010) and references therein.

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