Fig. 6.
Single-channel conductances recorded in human colonic SMC. A–C: using the inside-out configuration with symmetrical Cs+ (140 mM, ECl = −40 mV), 3 conductances were recorded in human colonic SMC. A: at a holding potential of −20 mV, single-channel openings were recorded that were −0.8 pA in amplitude (see all-points amplitude histogram, middle). A conductance of 27 pS was calculated by plotting peak channel amplitude at different voltages and fit with linear regression (top, right) (n = 5 of 26 patches). B: at a holding potential of −60 mV, single-channel openings were recorded that had an amplitude of −1.4 pA (middle). The calculated single conductance was 7.5 pS (right) (n = 6 of 26 patches). C: small-conductance single-channel activity revealed noisy-like openings at −60 mV but no channel openings at 0 mV (right) (n = 25 of 26 patches). HP, holding potential.