Alpha 2-adrenoceptor changes during cerebral ageing. The effect of Ginkgo biloba extract.

J Pharm Pharmacol

INSERM U. 316, Tours, France.

Published: January 1992

[3H]Rauwolscine binding to alpha 2-adrenoceptors in cerebral cortex and hippocampus membranes of young (4 months) and aged (24 months) Wistar rats has been investigated. In aged rats, Bmax values of [3H]rauwolscine binding were significantly reduced (25-32%) in the cerebral cortex and hippocampus, as compared with the number of alpha 2-adrenoceptors found in young rats. Chronic treatment with Ginkgo biloba extract did not alter [3H]rauwolscine binding in the hippocampus of young rats, but significantly increased (28%) the [3H]rauwolscine binding density in aged rats. These data confirm the previously described age-related noradrenergic alteration and suggest that noradrenergic activity in aged rats is more susceptible to Ginkgo biloba extract treatment.

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http://dx.doi.org/10.1111/j.2042-7158.1992.tb14357.xDOI Listing

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