Figure 7. R424H mutant-expressing PCs exhibit altered firing patterns.

A–D, representative firing patterns of PCs expressing GFP alone (A), WT subunits (B) or R424H mutant subunits (C and D). Approximately half of the R424H mutant-expressing PCs fired at the onset of current injection (onset-type; C). The action potentials were evoked by long depolarizing current injection (200 ms duration). The resting membrane potentials were adjusted to −60 mV. E, comparison of firing patterns. The χ² test was used for the statistical analyses. F, the firing frequency of the tonic-type cells is plotted as a function of injected current. *P < 0.05 and ***P < 0.001.