Figure 2. Currents through F380Y and F380I channels are iberiotoxin sensitive and have reduced single channel conductance compared to wild-type hSloα channels.

A, examples of currents elicited from wild-type, F380Y and F380I channels by voltage steps from -80 to +80 mV in outside-out patches. In all cases, the current was significantly reduced by application of 100 nm iberiotoxin (IbTX). The [Ca²⁺] in the pipette was 10 μm for wild-type, ‘zero’ for F380Y and 100 μm for F380I. B, single channel currents recorded at +80 mV for wild-type, F380Y and F380I channels, as indicated. C, a plot of the single channel current against membrane potential for wild-type (○, n = 5), F380Y (▵, n = 3) and F380I (□, n = 3) channels. Error bars (s.e.m.) are within the symbols.