Alpha 2-adrenoceptor changes during cerebral ageing. The effect of Ginkgo biloba extract.
[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.
INSERM U. 316, Tours, France.
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Huguet
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Tarrade
D000375:Aging / Q000187:drug effects / Q000502:physiology*; D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism*; D002540:Cerebral Cortex / Q000187:drug effects / Q000378:metabolism; D020441:Ginkgo biloba; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism; D007700:Kinetics; D008297:Male; D010936:Plant Extracts / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects / Q000502:physiology*; D015016:Yohimbine / Q000493:pharmacokinetics; D000096983:Ginkgo Extract
D010936:Plant Extracts; D011942:Receptors, Adrenergic, alpha; D015016:Yohimbine; C063170:Ginkgo biloba extract; D000096983:Ginkgo Extract