Excitatory and inhibitory amino acid binding sites in human dentate nucleus

Abstract

Autoradiography of excitatory and inhibitory amino acid binding sites in human dentate nuclei indicated virtually no binding to N-methyl- d-aspartate (NMDA) or γ-aminobutyric acid B (GABA B) binding sites, and a low density of kainate binding sites. α-Amino-3-hydroxy-5-methylisoxazole-4-propionic acid, metabotropic-quisqualate, benzodiazepine, and γ-aminobutyric acid A (GABA A) binding sites were present in moderate abundance. Our NMDA results differ from those found previously in rodents. GABA A receptors are probably the primary mediators of inhibitory neurotransmission and α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid and metabotropic-quisqualate receptors are probably the primary mediators of excitatory neurotransmission within the human deep cerebellar nuclei.