TABLE I.

Parameters Derived from the Variations in Rates of Ryanoid Association with, and Dissociation from, Individual RyR2 Channels and Binding to Populations of Channels in Intact SR Vesicles

	10-O-succinoylryanodol (formal charge −1)	Ryanodol (formal charge 0)	21-amino-9a-hydroxyryanodine (formal charge +1)
Slope (zonF/RT)	0.021 ± 0.003 (r = 0.75)	0.041 ± 0.003 (r = 1)	0.051 ± 0.002 (r = 1)
zon	0.54	1.03	1.29
Slope (−zoffF/RT)	−0.028 ± 0.005 (r = 0.75)	−0.019 ± 0.002 (r = 1)	−0.034 ± 0.002 (r = 1)
zoff	0.70	0.48	0.87
ztotal	1.24	1.51	2.16
kon at 0 mV (μM−1s−1)	0.002	0.035	0.365
koff at 0 mV (s−1)	0.082	0.095	0.990
Kd at 0 mV (μM)	35.620	2.810	2.790
Kd (binding, μM)	19.5 ± 4.0a	7.0 ± 2.0,a 5.8 ± 0.9b	3.7 ± 0.6b

^aSheep cardiac SR.

^bRabbit skeletal SR.