Fig. 8.
Transient outward potassium currents (IKA) in neurons at E16 and P14. A: transient outward current (TOC) and sustained outward current (SUS) at E16 (a) and P14 (b). The IKA were evoked by hyperpolarization to −120 mV, followed by depolarization to −30 mV. The SUS were evoked by depolarization to −30 mV without the hyperpolarizing prepulse. The TOC were eliminated by 4-AP in the same neurons at E16 (c) and P14 (d). Dashed lines indicate 0 pA level. B: incidence of neurons with IKA at different ages. C: activation and inactivation curves for IKA at E14/16 (filled and open circles) and P14–20 (filled and open triangles). Values are means ± SE. D: developmental changes in amplitude (a) and decay time constant (b) of IKA. Values are medians within the 25th–75th percentile range. Horizontal bars above each graph indicate pairs with significant differences; *P < 0.01 and **P < 0.05, Mann-Whitney test.