Fig. 3.
αG667A mutation increases channel open probability (Po). A: cell-attached patch-clamp recordings were obtained from oocytes expressing αβγ or αG667Aβγ channels. Patches were clamped at −100 mV (membrane potential) for wild-type channels or −80 mV for αG667Aβγ channels. Both bath and pipette solutions contained 110 mm Na+. Recordings containing single channels lasting for at least 5 min were selected for analysis. Representative recordings of single-channel currents are shown. C and O represent closed and open states, respectively. The scale bars indicate current amplitude (pA) and time (s). B: Po was determined as described under materials and methods and presented for multiple experiments (n = 5) and as means ± SE. The Po of αG667Aβγ (0.30 ± 0.02) was significantly greater than that of wild-type αβγ (0.11 ± 0.04). #P = 0.01; n = 5.