Figure 2.

Development of action potential kinetics in NM. (A) Representative voltage traces (30 superimposed) in response to sustained threshold current injections. Threshold current is defined as the minimum amount of current required for NM neurons to generate an AP ~50% of the time across 30 repetitive stimulations. The injected +300 pA current shown below the traces was determined as the threshold current for this E20 NM neuron. Arrow depicts ~50% AP failures. (B) Representative APs for each age group evoked by sustained current injections at strength 25% above threshold current. AP kinetics were calculated and plotted as a function of age and are shown in (C–F). (C–F) Population data showing developmental changes in AP latency (C), AP half width (D), AP rise rate (E), and AP fall rate (in absolute value, F) as a function of age. Open circles represent an individual neuron and solid bars represent the average for each age group. *p < 0.05, Bonferroni adjusted t-test.