Multiple sites involved in glutamatergic neurotransmission were examined in the cerebellar cortex of 6 patients with Alzheimer's disease and 6 age-matched control patients by using quantitative ligand-binding autoradiography. Quisqualate (AMPA) receptor binding was markedly reduced in the molecular layer of the cerebellum from patients with Alzheimer's disease (167 +/- 13 pmoles/gm) compared with control patients (280 +/- 13 pmoles/gm). In adjacent sections from the same patients and controls, there was preservation of kainate and N-methyl-D-aspartate receptor binding in the cerebellum from patients with Alzheimer's disease compared with control patients. Neuropathological examination of the cerebellar cortex revealed the presence of plaques and preservation of Purkinje cells in the patients with Alzheimer's disease.