Article: Early electrophysiological abnormalities in lumbar motoneurons in a transgenic mouse model of amyotrophic lateral sclerosis.

V_rest, resting potential; R_in, input resistance; anti and ortho AP, amplitude of antidromic and orthodromic action potentials, respectively; half-width, measured as the time (ms) spent by the membrane potential above 50% of the total amplitude of the action potential; time to peak, measured as the time needed for the potential to deviate from 5 to 95% of the total amplitude; AHP, postspike after-hyperpolarization amplitude, duration and half duration; rheobase, lowest intensity of current injected through the electrode to construct the frequency–intensity (F–I) curve eliciting an action potential was used as the criterion for rheobase current (nA) measurements; threshold, voltage threshold measured at the foot of the orthodromic action potential; slope, slope of the steady-state F–I curves; I_max, maximal current injected through the microelectrode to obtain the maximal steady-state frequency; f_max, maximal steady-state frequency; τ_m and τ₁, membrane time constants; C_m, membrane capacitance; L, electrotonic length; n, number of cells; WT, wild-type. All values are means ± SEM. *P < 0.05, ***P < 0.005.