Immunostaining was performed as described previously11. In brief, cells were fixed in 4% neutral-buffered paraformaldehyde (PFA) for 20 min at room temperature. For detection of GABA, 0.05% glutaraldehyde (Electron Microscopy Sciences) was included in the fixative. All antibodies, sources and dilutions are listed in Supplementary Table 3. Cell populations were counted among total cells (Hoechst labeled) or neurons (Tuj1+) using the ImageJ software. At least five fields of each coverslip were chosen randomly, and three coverslips in each group were counted. Data were expressed as mean ± s.e.m.
