Fig. 1.

Early patch clamp recording of Na⁺ currents in voltage-gated Na⁺ channels. The outside-out patch from a bovine chromaffin cell is depolarized in a voltage step from −80 mV to −50 mV. Each channel opening is seen as a downward deflection as Na⁺ ions flow briefly (open time ~1 ms) in from the extracellular solution when one or two Na⁺ channels are opened stochastically. (Fenwick et al. (1982).