Abstract
Neuroleptic drugs (D2 blockers) which are used for the treatment of psychotic disorders, especially for schizophrenia, are known to produce extra-pyramidal side effects (EPS). Catalepsy was induced by these drugs in animals and these animals have been used as models to study the extra-pyramidal side effects which are associated with anti-psychotic agents in human beings. In the present study, we found out the protective effect of the aqueous extract of Mentha arvensis (MA) on haloperidol (2.0 mg/kg po administration) induced catalepsy in mice, by employing the standard bar test and the assessment of the locomotor activity. The mice were allocated to six groups, with each group containing seven animals. The effects of the test drug MA (500 and 1000mg/kg doses) and the standard drug, trihexyphenidyl (0.1mg/kg) were assessed after their repeated dose administration in mice for fourteen days, 30 minutes prior to the administration of haloperidol. The mice were sacrificed on the fourteenth day and the TBARS, glutathione, SOD and the catalase activities in their brain tissues were estimated by using the Ohkawa et al., Sedlak and Lindsay, Clairbone, Marklund and Marklund respectively. A significant (P<0.001) reduction in the cataleptic scores was observed in the test drug treated groups as compared to the toxic control, with a maximum reduction in the group with a drug dose of 1000 mg/kg. Similarly, our study suggested that MA had significantly reduced othe xidative stress and the cataleptic score which was induced by haloperidol. Hence, it could be used to prevent the drug-induced extrapyramidal side effects.