(A) Representative recordings of voltage responses from pyramidal neurons after a 24-hour exposure to CTL, RG108 + APV, RG108 + NBQX + APV, or RG108 + TTX. (B) Mean AP firing rates evoked over a range of current intensities. Graph shows means ± SEM from cells pooled from at least three experiments for each condition (CTL, n = 7 cells; RG108 + APV, n = 5 cells; RG108 + NBQX + APV, n = 7 cells; RG108 + TTX, n = 7 cells).