Table 3.

Steady-state Activation Kinetics of the Four Analyzed Ca_V1.2 Isoforms Obtained in 5 mM Ba²⁺

Parameters/Splice Isoform	V1/2act. (mV)	klow	khigh	n
1a/8	−3.0 ± 1.0a	11.8 ± 1.2	52.6 ± 32.9	15
1a/8a	−3.5 ± 1.1b	10.1 ± 1.2	63.1 ± 22.7	11
1/8	−5.5 ± 1.0a,b,c	10.0 ± 1.2	28.9 ± 26.1	8
1/8a	−5.5 ± 1.1c	8.4 ± 1.5	33.3 ± 14.0	9

Half-maximal activation was determined by a dual Boltzmann function when G = 0.5G_max. Slope factors (k) are given for the low and high threshold components of the function. All data are represented as mean ± SE. For statistical significance, a one-way ANOVA was applied. Data were Bonferroni corrected, ^a/ap < 0.001, ^b/bp < 0.0001, ^c/cp <0.001.