Deficits in cholinergic enzymes and muscarinic receptors in the hippocampus and striatum of senescent rats: effect of chronic hydergine treatment.

Choline acetyltransferase and acetylcholine esterase activities in the hippocampus and striatum were significantly decreased in senescent (26-36 mo.) rats as compared with adult (11-12 mo.) animals. A significant reduction in 3H-QNB binding sites was also observed in the striatum from aged rats whereas in the hippocampus these binding sites were not influenced by age. A four week treatment of aged animals with Hydergine resulted in an increase in choline acetyltransferase activity so that the age-dependent deficit was no longer apparent.