Table 1

Parameters for inactivation kinetics of μ1 wild-type and mutant Na⁺ channels

Channel	Control		Control		R(+)-Bupivacaine		S(−)-Bupivacaine
Channel	V_0.5	k	S′_0.5	k_S′	S′_0.5	k_S′	S′_0.5	k_S′
	mV
Wild-type	−82.1 ± 1.4	5.4 ± 0.1	−63.0 ± 2.5	12.7 ± 1.1	−102.3 ± 0.5	7.6 ± 0.4	−102.5 ± 0.6	7.9 ± 0.5
		(n = 10)		(n = 22)		(n = 11)		(n = 11)
N434A	−69.5 ± 1.4	6.8 ± 0.4	−71.4 ± 0.1	5.5 ± 0.9	−97.9 ± 1.9	5.3 ± 1.7	−94.9 ± 1.6	4.9 ± 1.3
		(n = 4)		(n = 21)		(n = 10)		(n = 11)
N434F	−96.3 ± 1.8	6.3 ± 0.2	−82.2 ± 0.7	11.7 ± 0.6	−111.5 ± 2.7	6.8 ± 2.4	−113.8 ± 4.3	7.1 ± 3.7
		(n = 11)		(n = 17)		(n = 4)		(n = 4)
N434W	−98.2 ± 0.4	7.4 ± 0.3	−74.4 ± 2.0	16.0 ± 1.2	−115.7 ± 1.6	9.2 ± 1.5	−115.5 ± 2.6	7.1 ± 2.3
		(n = 5)		(n = 9)		(n = 5)		(n = 4)
N434Y	−114.2 ± 2.7	8.6 ± 0.1	−36.6 ± 30.6	36.8 ± 8.7	−133.5 ± 3.4	9.1 ± 2.7	−139.0 ± 5.3	9.3 ± 3.7
		(n = 7)		(n = 8)		(n = 4)		(n = 4)
N434T	−78.9 ± 1.2	7.3 ± 0.2	−65.2 ± 0.3	6.2 ± 0.2	−105.5 ± 2.3	8.5 ± 2.1	−99.5 ± 1.9	7.8°1.7
		(n = 7)		(n = 11)		(n = 5)		(n = 6)
N434C	−98.8 ± 1.9	6.4 ± 0.2	−86.9 ± 0.3	9.7 ± 0.3	−124.0 ± 7.5	6.8 ± 6.5	−119.5 ± 5.7	4.2 ± 5.8
		(n = 10)		(n = 25)		(n = 11)		(n = 10)
N434D	−87.3 ± 0.8	5.6 ± 0.4	−53.3 ± 9.1	16.8 ± 2.7	−110.9 ± 0.8	9.2 ± 0.7	−111.6 ± 0.6	8.4 ± 0.5
		(n = 5)		(n = 20)		(n = 11)		(n = 9)
N434K	−77.7 ± 1.3	7.0 ± 0.4	−54.0 ± 6.6	14.4 ± 2.0	−88.9 ± 1.1	5.9 ± 1.0	−92.6 ± 1.6	7.3 ± 1.4
		(n = 9)		(n = 15)		(n = 8)		(n = 7)
N434R	−83.3 ± 0.5	6.1 ± 0.1	−62.6 ± 5.9	15.8 ± 2.5	−97.1 ± 0.6	9.6 ± 0.5	−92.2 ± 0.7	9.8 ± 0.6
		(n = 9)		(n = 16)		(n = 8)		(n = 8)

The values for the voltage dependence of fast inactivation V_0.5and k (mean ± S.E., n = number of experiments) and the slow inactivation S′_0.5 and k_s′ (fitted values ± S.E.) in the absence and presence of 100 μM (μl wild-type, μl-N434A, μl-N434T, μl-N434D, μl-N434K, μl-N434R) or 10 μM (μl-N434C, μl-N434F, μl-N434Y, μl-N434W) bupivacaine enantiomers were determined as described in Fig. 2.