Fig. 4.31. Gating in single potassium channels: Patch clamp recording of unitary K currents in a squid giant axon during a voltage step from -100 to +50 mV. (A) Nine consecutive trials showing channels of 20-pS conductance filtered at 2-KHz bandwidth. (B) Ensemble mean of 40 trials. T = 20 °C. (From Hille, 1992, based on data from Bezanilla F and Augustine CK, 1986.).