Figure 3.

Ultrastructural analysis of GABAergic and glutamatergic synapses in culture. EM micrographs of glutamatergic and GABAergic synapses in WT (A–G) and KO (H–M) neuronal cultures. A–G, In the WT, GABAergic axon terminals (inh) establish inhibitory synapses with cell bodies (soma) and dendritic shafts (Den), and glutamatergic axon terminals (b) establish excitatory synapses with dendritic shafts (Den) and spines (s) of hippocampal neurons. H–M, In the KO, GABAergic (inh) and glutamatergic (exc) axon terminals were also detected, but the GABAergic axon terminals were generally smaller in size than those in the WT. Scale bars, 0.5 μm. The density of glutamatergic synapses did not change between WT and KO cultures, but there was a significant reduction in GABAergic synapses in the KO cultures (see Results).