Ginkgo biloba normalises stress-elevated alterations in brain catecholamines, serotonin and plasma corticosterone levels

Stress and depression and associated mental health problems have increased tremendously in modern times. The search for effective and safe alternatives from natural sources especially plant products should, therefore, continue. Forced immobilization is one of the best explored models of stress in rats and the role of corticosterone, serotonin and catecholamines, i.e. norepinephrine (NE), dopamine (DA) is well documented. Numerous studies have shown that Ginkgo biloba has antioxidant and neuroprotective properties and utility in cerebrovascular insufficiency and impaired cerebral performance. We investigated the effect of G. biloba on whole brain catecholamine, serotonin and plasma corticosterone levels following 1, 2 and 4 h restraint stress using HPLC and also plasma corticosterone using luminescence spectrophotometry. G. biloba extract (14 mg/kg p.o.) restored restraint stress-induced elevation in whole brain levels of catecholamines (NE, DA), 5-HT and plasma corticosterone to near normal levels. Further studies are warranted to explore the clinical potential of this encouraging lead in the management of stress and to elucidate the mechanisms involved.