Effect of Excitatory Amino acid antagonist on haloperidol induced Parkisonian Symptom in Rat

This study investigated the effect of ketamine, a s elective non competitive antagonist of N-methyl-D- Aspartate (NMDA) on haloperidol (0.25 mg/kg) induce d parkisonian symptoms in Wistar rats of both sexes, average weight 150g. The aim of the study fo cused on the hypothesis that blockade of NMDA receptor could have beneficial effect on haloperido l induced parkinsonian symptoms.Hypolocomotion was induced intraperitoneally (i.p) with 0.25mg/kg haloperidol, a neuroleptic. The open field test was used for assessment. Albino rats were divided into 5 groups of 6 animals each (group i, was not treat ed (Control), group ( ii and iii) were treated with 0.25mg/kg and 0.5mg/kg, respectively, group( iv) re ceived 2.5mg/kg ketamine and group (v) received 0.25mg/kg of haloperidol and 2.5mg/kg of ketamine concomitantly. Results obtained showed ketamine in the concentration used significantly (P<0.01) improved locomotor activity in haloperidol induced hypolocomotion, similarly exploration, (rearing an d rearing against the wall) was significantly unalter ed, furthermore, the result seem to unveil the protective effect of ketamine in the concentrations used in this work.