Fig. 6.

Benzodiazepine sensitive γ2 containing GABA_AR tonic current is enhanced by muscimol treatment. Neurons were incubated in standard extracellular saline containing for t = 0 min (t0), in saline containing muscimol for 30 min (t30), or pretreated with 1 µM U0126 for 10 min then treated with muscimol for 30 min (t30 + U0126). A. Baseline currents were recorded in extracellular saline containing TTX, DNQX, and APV, followed by perfusion of flurazepam (FLZ). Benzodiazepine sensitive tonic current was expressed as the difference in baseline current before and after application of FLZ (3 µM). After subtracting baseline from the current evoked by FLZ, the tonic current was normalized to cell size. Representative traces with corresponding all-point histograms fitted with single Gaussian functions are shown. B. Muscimol treatment increased the γ2 containing GABA_AR contribution to tonic current, which was blocked by U0126 pretreatment: in pA/pF t0 = 0.61 ± 0.14, t30 = 2.04 ± 0.39, t30 + U0126 = 0.46 ± 0.21 (Mean ± SEM, n = 6–7 neurons per condition, one way ANOVA, Tukey's multiple comparisons test). *p < 0.05, **p < 0.01.