Fig. 1.

DA-like neurons of Gabrg2^DATCreER mice have impaired reactions to GABA_A receptor agonist and antagonist. a–d show raw traces of extracellularly recorded firing of four representative DA-like neurons from WT a, c and Gabrg2^DATCreER mice b, d. Top traces show firing during baseline conditions. Bottom traces show alternation of firing of the same neurons induced by application of the GABA_A receptor agonist muscimol (MUS) or the GABA_A receptor antagonist bicuculline (BIC). e–h show firing and bursting rate histograms of the example neurons shown on panels a–d, respectively. Time of drug application is marked with a black bar. Note that muscimol application induced a complete cessation of DA-like neuron firing in WT animals a, e and only partial reduction of DA-like neuron firing in Gabrg2^DATCreER mice. Also increase of DA-like neuron firing induced by application of bicuculline was significantly larger in WT c, g comparing to Gabrg2^DATCreER mice d, h animal. On i–k baseline and drug altered firing of all recorded DA-like neurons in WT (•—baseline, ■—drug) and Gabrg2^DATCreER (○—baseline, □—drug) mice, are shown. Note that under baseline conditions, total and extraburst firing rates were significantly higher in mutant comparing to control animals. l–n show the relative change in firing induced by muscimol l, and bicuculline m, n. Vertical lines with whiskers indicate the mean value and SEM. * or ^# indicates Bonferroni corrected t tests that resulted in p < 0.05, ** indicates p < 0.01 and *** indicates p < 0.001