FIGURE 3.

Cultivation temperature does not affect gating currents of Eag channels. A, representative gating current traces evoked by depolarizing voltages recorded in N-methyl-d-glucamine solutions from eag-transfected CHO cells cultivated at 26 °C (left) or 37 °C (right). The arrows indicate the region for obtaining off-gating charge movement (Q). B, summary of percentage of eag- or shaker-transfected CHO cells that exhibited measurable gating currents. No gating currents were detected from any untransfected CHO cell. There were statistically significant differences between untransfected and eag-transfected cells cultivated at either 26 or 37 °C (**, p < 0.01, logistic regression), although the probability of gating current occurrence was not different between cells grown at 26 or 37 °C (p values shown in B). C, normalized Q-V curve determined from eag-transfected cells cultivated at 26 or 37 °C. Solid lines represent fits of Boltzmann function. Fitted values of V½ were −13.4 ± 7.2 mV, n = 10, in cells cultivated at 26 °C and −0.2 ± 6.9 mV, n = 11, in cells at 37 °C. p > 0.05 for the comparison of V½ values between the two groups using one-way ANOVA. D, representative on-gating current traces recorded in TEA solutions from eag-transfected CHO-K1 cells cultivated at 26 °C (top) or 37 °C (middle). On-gating currents from shaker-transfected cells (bottom) were used for comparison.