Figure 8. Voltage-dependent rectification by K_ATP channels in the inside-out recording configuration.

A, steady-state channel activity recorded in symmetrical 140 mm K⁺-containing solution for membrane potentials ranging between –80 and +80 mV (Note: the larger brief channel openings marked with an asterisk on the +80 mV record are clipped openings of a much larger unidentified channel). B, I–V curve for the single-channel currents shown in A. (Note: channel slope conductance was measured over the relatively linear region of the curve between –25 and –80 mV). C, rectification of single-channel currents as revealed by slowly ramping patch potential between –61 and +59 mV (ramp 67 mV s⁻¹). The patch contained at least two K_ATP channels.