Table 1.

Best-fitting parameters describing the voltage-dependence of charge movement.

	Qmax (nC µF−1)	VQ1/2 (mV)	K
WT (n = 13)	30 ± 8	−14 ± 2.2	16 ± 1.5
DKO	35 ±11	−24±1.7	14 ± 1.9
(n = 15)	(P = 0.724)	(P = 0.001)	(P = 0.426)

Data points were fitted to a Boltzmann equation of the form: Qon = Qmax/[1 + exp(V_Q1/2 − Vm)/K], where Qmax is the maximum charge, Vm is the membrane potential, VQ_1/2 is the charge movement half-activation potential and K is the steepness of the curve as described in ref. 27. The number of FDB fibres from three to four mice is between parentheses. Results are expressed as the mean ± s.e.m. Statistical significance was assessed using Student’s t-test. The α-level was set at P=0.05.