FIG. 3.
PCB 202 influences RyR1 channel gating kinetics in a concentration-dependent manner. (A) Schematic diagram of the RyR1 channel reconstitution across the BLM chamber. (B) Representative traces of single RyR1 channel gating activity before and after stepwise increase in PCB 202 concentrations. Recordings of channel gating activity were measured for several minutes before the sequential addition of PCB 202 on the cis (cytoplasmic) side of the RyR1 channel. Traces shown are representative sections of the RyR1 channel. (C) Concentration-dependent change in open probability (Po, a) and corresponding changes in the mean open dwell time (τo, b) and the mean closed time (τc, c). Channel kinetic data in (C) are the Mean ± SD from 4 different recording time periods (eg, parameter during the initial 20 s exposure to given treatment). Abbreviations: Ground (GND), polychlorinated biphenyl (PCB), cytoplasmic side (cis), luminal side (trans), voltage input (volt-input), amplifier to recorded (Amp -> Rec), open channel state (O); closed channel state (C); sub-conductance state (S). Differences indicated in panel (C) were assessed using repeated measures ANOVA with a Tukey post-hoc analysis. **P ≤ .01 relative to the control; †P ≤ .05 relative to PCB 202 at 100 nM. n = 4 time periods.