Protective effect of Ocimum sanctum Linn. leaf extract on ethanol withdrawal syndrome in Wistar rats

Objective: To evaluate the effects of Oscimum sanctum L(O. sanctum), an important medicinal herb, on alcohol withdrawal syndrome in Wistar rats. Methods: Liquid diet with 7.2%, v/v ethanol was administered to the rats for 21 d. Control group animals received sucrose as an isocaloric liquid diet. After alcohol withdrawal, rats were examined at 6 th and 24 th hour for major withdrawal signs that included anxiety and hyper locomotor activity. Ethanol withdrawal anxiety was tested using elevated plus maze, light and dark model; the hyper locomotor activity using actophotometer. O. sanctum leaf extract(100, 200 and 300 mg/kg, oral) and diazepam(2 mg/kg, i.p) were administered to the treatment group animals 30 min before alcohol withdrawal estimation. Drug treatment was also given 30 min before the second observation at 24 th hour. On the last day of the protocol, rats were sacrificed by cervical dislocation liver, kidney and brain were isolated and preserved in formalin for further histopathological examination. Results: Findings from the present study revealed that O. Sanctum leaf extract treatment at doses 100, 200 and 300 mg/kg, oral had a significant protective effect on signs and symptoms of ethanol withdrawal in alcohol-dependent rats. However, no remarkable pathological and microscopic alterations were observed in histopathological examination. Conclusions: O. sanctum seems to be an active drug for the treatment of alcohol abstinence syndrome.

Effects of the aqueous extract of Schizandra chinensis fruit on ethanol withdrawal-induced anxiety in rats

Background We previously demonstrated that the aqueous extract of the Schizandra chinensis fruit （AESC） ameliorated Cd-induced depletion of monoamine neurotransmitters in the brain through antioxidant activity.In the present study,we investigated the effect of AESC on anxiety-like behavior and the levels of norepinephrine and 3-methoxy-4-hydroxyphenylglycol （a metabolite of norepinephrine） in different brain regions during ethanol withdrawal in rats.Methods Male Sprague-Dawley rats were treated with 3 g/kg of ethanol （20％,w/v） or saline by daily intraperitoneal injection for 28 days followed by three days of withdrawal.During withdrawal,rats were given AESC （100 mg.kg 1.d-1 or 300 mg.kg 1·d1,P.O.） once a day for three days.Thirty minutes after the final dose of AESC,the anxiogenic response was evaluated using an elevated plus maze,and the plasma corticosterone levels were examined by radioimmunoassay.Meanwhile,the concentrations of norepinephrine and 3-methoxy-4-hydroxy-phenylglycol in the hypothalamic paraventricular nucleus and hippocampus were also measured by high performance liquid chromatography.Results Rats undergoing ethanol withdrawal exhibited substantial anxiety-like behavior,which was characterized by both the decrease in time spent in the open arms of the elevated plus maze and the increased level of corticosterone secretion,which were greatly attenuated by doses of AESC in a dose-dependent manner.The high performance liquid chromatography analysis revealed that ethanol withdrawal significantly increased norepinephrine and 3-methoxy-4-hydroxy-phenylglycol levels in the hypothalamic paraventricular nucleus,while not significantly altering them in the hippocampus.Similar to the results from the elevated plus maze test,the AESC significantly inhibited the elevation of norepinephrine and its metabolite in the hypothalamic paraventricular nucleus in a dose-dependent manner.Conclusions These results suggest that AESC attenuates anxiety-like behavior induced by ethanol withdrawal through modulation of the hypothalamic norepinephrine system in the brain.