Fig. 3: Astrocytic GABA-T selectively modulates tonic inhibition but not phasic inhibition in dentate GCs.
a, A scheme of the Cre-dependent termination of shABAT expression specifically in astrocytes. b, Immunostaining for GABA-T and GFAP in the control, general GABA-T KD and astrocytic GABA-T rescue groups. The GFP–Cre signal is localized in the nucleus, and the mCherry (mCh) signal indicates the expression of the shRNA. The magnified inset image shows the astrocyte indicated by the yellow arrowhead (inset scale bar, 20 μm). c, The violin plots comparing the average intensity of GABA-T staining in the GFAP+ areas among the three groups. d, A workflow illustrating the silencing of the GABA-T gene (either including or excluding astrocytes) in the dorsal hippocampal DG, followed by the brain slice preparation and whole-cell voltage-clamp recordings in GCs. e, The representative traces of GABAAR-mediated phasic and tonic GABA currents from the general GABA-T KD and astrocytic GABA-T rescue groups. f, Comparative bar graphs of the tonic GABA current (left), sIPSC amplitude (middle) and sIPSC frequency (right). sIPSCs recorded before the bicuculline (Bic) treatment were analyzed. n = 5 mice per group. The data are presented as the mean ± standard error of the mean. The individual dots refer to cells, unless otherwise specified. The P values were obtained via the Kruskal‒Wallis test for c and an unpaired t-test for f (left and middle), as well as a Mann‒Whitney test for f (right). ***P < 0.001, ****P < 0.0001; nonsignificant (ns) indicates a P > 0.05.
