Figure 10. Fast and slow A-currents in 7- and 15-day-old rats.

Fast and slow A-currents obtained from the superior salivatory neurones labelled from the chorda-lingual nerve of 7-day-old (A and C, respectively) and 15-day-old rats (B and D, respectively). At a holding potential of −60 mV, depolarizing command pulses of 1500 ms duration stepped to −10 mV for A and C, and stepped between −60 and −10 mV for B and D were applied after a 1000 ms hyperpolarizing prepulse to −120 mV. A hyperpolarization-activated inward current (arrowhead in B) is seen during the hyperpolarizing prepulse in the neurone of a 15-day-old rat displaying the fast A-current.