Neurotransmitter receptors in olivopontocerebellar atrophy: an autoradiographic study.

We used in vitro receptor autoradiography to study four cases of olivopontocerebellar atrophy (OPCA) and three age- and postmortem delay-matched controls. In OPCA, benzodiazepine receptors were unchanged in cerebellar cortex but increased in the dentate nucleus, perhaps related to loss of Purkinje cell or brainstem afferents. Muscimol binding was reduced primarily in the granule cell layer. The density of muscarinic cholinergic receptors was reduced in molecular and granule cell layers, but appeared increased in the dentate.