Figure 3. Tonic inhibition and its potentiation by ethanol are unaltered in α1^H101R dentate gyrus molecular layer interneurons.

A) Amino acid alignment between α1 and α4 GABA_AR subunits showing the position of the critical amino acid residue difference for BZ sensitivity. Asterisks indicate identical amino acids. B) Voltage-clamp recordings from α1^H101R interneurons show a potentiation of the tonic inhibitory current by 30 mM ethanol. Left, baseline current plotted at 500-ms intervals in control (①), 30 mM ethanol (②) and BMI conditions (Vh= -70 mV, horizontal bars indicate perfusion of the drugs); Right, Gaussian fits to the all-point histograms of the baseline current recorded during each condition. C) Recording segments low-pass filtered at 1 KHz in control and ethanol conditions. D) Averaged sIPSC recorded in control and ethanol conditions from two different cells. E) Box-chart of all tonic currents recorded. Box represents the 25, 50, 75 percentiles, with the superimposed mean ± SEM. Circles connected by lines represent paired individual values of the tonic inhibitory currents recorded in a given cell under the two conditions. Asterisk represents p=0.0005 paired t-test; n=14.