The Cellular Localisation of GAB A_A and Glycine Receptors in the Human Basal Ganglia

摘要

We have investigated the cellular localisation of GABA_A (GABA_AR) and glycine (GLYR) receptors in the human basal ganglia using imrmmohistochemical techniques and light and confocal laser scanning microscopy. GABA_AR were most highly expressed on GABAergic striatal interneurons (alpha_1, beta_(2,3), gamma_2 subunits), cho-linergic interneurons (alpha_3), and striatal projection neurons (alpha_2, alpha_3, beta_(2,3), gamma_2 subunits). GLYR were present mainly on ChAT and a subset of parvalbumin striatal interneurons. The neurons of the globus pallidus (GP) showed high levels of alpha_1, alpha_3, P_(2,3), gamma_2 subunits (no alpha_2) whereas GLYRs were only distributed on a subpopulation of pallidal neurons. In addition, GLYRs selectively stained neurons in the intermedullary laminae of the GP. Neurons in the SNr and SNc were labelled with GLYR but had different GABA_AR subunit configurations. SNr neurons expressed alpha_1, alpha_3, beta_(2,3), gamma_2 (no alpha_2) subunits and SNc neurons expressed mainly GABA_AR alpha_3 gamma_2 subunits. These results demonstrate that in the basal ganglia, neurons are generally associated with one of four different GABA_A receptor configurations. This suggests that throughout the basal ganglia GABA acts via GABA_A receptors with various subunit combinations and that glycine acts through glycine receptors on neurons of the SNr and SNc and groups of interneurons scattered throughout the striatum and GP.