Aging and the regulation of striatal dopaminergic mechanisms in mice

PK Randall, JA Severson and CE Finch

Compensatory responses of striatal dopaminergic mechanisms to chronic drug treatment were tested in C57BL/6J and C57BL/6NNia male mice during the adult lifespan (5, 12, and 24 to 26 months). Chronic treatment with haloperidol (dopamine antagonist) (1.2 or 2 mg/kg/day for 21 days) induced supersensitivity in younger mice (5 and 12 months) as monitored by increased striatal spiroperidol binding sites and increased intensity of apomorphine-induced stereotyped behavior; in contrast, old mice were unaffected. However, chronic treatment with bromocriptine (dopamine agonist) (15 mg/kg/day for 7 days) induced desensitization at all ages, as monitored by reduced spiroperidol binding sites and reduced intensity of stereotyped behavior.

Volume 219, Issue 3, pp. 695-700, 12/01/1981
Copyright © 1981 by American Society for Pharmacology and Experimental Therapeutics