Fig. 7.

hP2X7R^G345C single-channel modifications by MTS reagents that were pipette applied to the intracellular side of outside-out patches. (A and B) The representative current traces were recorded from inside-out patches excised from hP2X7R^G335C-expressing oocytes without MTSET⁺ (A) and with 0.025 mM MTSET⁺ (B) in the patch pipette. The horizontal bar indicates the period of ATP⁴⁻ application. The corresponding single-channel currents were calculated from the adjacent amplitude histograms. (C–E) Effect of intracellularly applied MTSET⁺ on current noise kinetics. Shown are original traces recorded with pipette solutions without MTSET⁺ (C) or with 0.025 mM MTSET⁺ (D). The running average current I_runavg is shown as a white line. The corresponding time-dependent smoothed noise σ²_runavg is shown in the adjacent panels. (E) Statistics for the relative noise (σ²/I_mean,500) of the first 500 ms during the very first ATP⁴⁻ application. The means from 16 and 7 patches excised without and with MTSET⁺ in the pipette, respectively, are significantly different. For details, see SI Appendix, SI Materials and Methods.