Figure 4.
Properties of L247T α7 nAcChoR-channels activated by 5HT. (A) Examples of single-channel currents at −59 mV EMP. (B) Distribution of single-channel amplitudes at same membrane potential, with 20 μM 5HT in the patch pipette, in the same patch. Histogram best fitted as in Fig. 1B, with mean of 2.72 ± 0.02 pA (n = 573). (C) Mean channel current amplitudes vs. pipette potential, plotted and fitted as in Fig. 1C, yielding the indicated slope conductance. Same patch as A and B. (D) Histogram of open durations fitted as Fig. 1D, with τ1 = 5.04 ± 0.02 (36%), τ2 = 27.4 ± 0.01 (64%), and τop as indicated. Same patch as A–C. (E) Voltage dependence of mean open time obtained from five patches (five cells, three donors). Values of τop, errors, and plot, as in Fig. 1E. Note the decrease of τop with hyperpolarization.