Fig. 3.

ACM-hSOD1^G93A rapidly increases neuronal excitability. A: whole cell current-clamp recordings of control primary spinal neuron in the presence of ACM-hSOD1^G93A. Action potentials (APs) are evoked by injection of rectangular depolarizing current pulses (bottom; 10, 20, and 40 pA for 300 ms). Representative membrane potential traces show that bath application of ACM-hSOD1^G93A to 5–7 DIV primary spinal neurons rapidly increases the firing frequency (arrowheads). B: average change in AP firing frequency produced by 30-min application of ACM-hSOD1^G93A or ACM-hSOD1^WT. Values represent means ± SE from at least 5 neurons/time point, analyzed by t-test. *P < 0.05 compared with ACM-hSOD1^WT at same time point.