Attenuation of stress-induced behavioral deficits by lithium administration via serotonin metabolism

Abstract

BackgroundAlthough the mood stabilizing role of lithium is well established and the cognitive effects of lithium are also best demonstrated, but its primary effects on neurochemical and behaviors under stress condition remain ambiguous. Earlier studies have suggested that a single exposure to 2h immobilization stress alters memory in various memory tasks, decreases exploratory activity in open field test and increases serotonin metabolism. This study is designed to investigate the stress relieving effect of lithium in rats. MethodsRats were orally administered with lithium chloride (1mg/kg/ml) while controls received an equal volume of water for 21 days. After 21 days, each group of rats was sub-divided into stressed and unstressed groups. Animals of stressed group received immobilization stress for 2h and 24h following stress behavioral analysis was performed, after which animals were decapitated and their brain samples were collected for neurochemical estimation by HPLC-EC. ResultsResults of the present study show that 2h immobilization stress decreases locomotor activity while impairs memory performance. Prior administration of lithium attenuates memory impairment and locomotion suppressant effects of stress by reversing the stress induced brain serotonin metabolism in lithium treated rats. ConclusionThus, the results of this study suggest that lithium may recover behavioral and neurochemical impairments induced by stress.