Role of Shilajit in a murine model of haloperidol induced catalepsy.

Shilajit, an ayurvedic drug is a blackish-brown exudation obtained as a mineral resin or as a plant fossil. Experimental study has shown shilajit has nootropic and anxiolytic activities. The nootropic and anxiolytic actions have been attributed to the ability of shilajit to induce an increase in rat brain dopaminergic activity and a decrease in 5-HT turnover. Shilajit is one of the components of NR-ANX-C (a poly-herbal preparation), which has proven anticataleptic activity in a previous study conducted by us. Increased dopamine turnover in the rat brain with Shilajit and the anticataleptic activity of NR-ANX-C prompted us to assess the anticataleptic activity of Shilajit. Inbred albino mice were divided into five groups, each containing six animals. Both, the test drug, the Shilajit and the standard drug scopolamine were dissolved in 1% gumacacia solution. Catalepsy was induced with haloperidol (1.0 mg/kg; i.p.). The first group received the vehicle (10.0 ml/kg), the second group received scopolamine (1.0 mg/kg) and the remaining three groups of animals received the test compound Shilajit ( 2.5, 6.25 & 12.5 mg/kg) were assessed after single and repeated dose administration for seven days, 30 minutes prior to the haloperidol. In the present study, pretreatment of aqueous extract of shilajit protected the mice from catalepsy induced by haloperidol as effectively as the standard drug scopolamine and in fact better than scopolamine on repeated administration. Our study suggests that Shilajit can be explored as an adjuvant drug in preventing and treating the extrapyramidal side effects of antipsychotic agents in clinical practice. [ABSTRACT FROM AUTHOR]