Figure 2.

Transient current recovering effect of EIAs on ASIC3 channels. (A,B) Dual effect of THP preincubation reflected in sustained current generation together with inhibition of steady-state desensitization. Whole-cell currents recorded from human (A) or rat (B) ASIC3 channels held at pH 7.3 and 6.8, respectively were measured with pH 5.5 stimulus at different THP concentrations. (C) ASIC3 steady-state desensitization of human and rat channels by increasing proton concentrations in the conditioning period. Each point is presented as mean ± SE of seven measurements. (D,E) Traces for human (D) and rat (E) ASIC3 currents measured for non-desensitized channel state at resting pH 7.8 (left) and for desensitized channel state in the presence of reticuline (in the center) and THP (on the right). (F) Dose-response curve for THPs’ transient current recovering effect on hASIC3 and rASIC3. I_max was predicted by the fitting of dose dependences by a logistic equation independently for each cell. Each point is presented as mean ± SE of 4–5 measurements. (G) Comparative chart for calculated maximal amplitude of transient currents (recovered by THP from desensitization) to measured transient currents in the control by a pH drop of 7.8–5.5. Data for rASIC3 (n = 4) and hASIC3 (n = 5) are presented as mean ± SE.