Figure 1.

Larger tonic GABA_A receptor-mediated current in CGCs of α1^−/− mice. A, Representative current traces from cerebellar granule cells in brain slices of wild-type (+/+, top) and α1 knock-out (−/−, bottom) mice. Application of the competitive GABA_A antagonist BIC (25 μm) reveals a tonic conductance. B, Amplitude distributions of current traces in A. Distributions were drawn from current segments immediately preceding BIC application. Mean baseline current during application of BIC (25 μm) was adjusted to 0. The average values of tonic current, normalized to the cell capacitance were as follows: 6 ± 0.75 pA/pF, n = 31 for +/+; 9.75 ± 0.75 pA/pF, n = 32 for α1^−/−; p < 0.02. Tonic current was calculated as described in Materials and Methods. Data are derived from >15 mice in eight litters. For values of variance and coefficient of variation of the baseline noise, see Results.