Abstract

Md. Mokarram Hossain*, Israt Jahan Biva, Rumana Jahangir and Md. Mynol Islam Vhuiyan

In the present study, we have investigated the possible CNS (Central Nervous System) depressant and analgesic action of the methanol extract of Aphanamixis polystachya leaf. Its CNS depressant activity was evaluated by using thiopental sodium- induced sleeping time, hole cross and open field tests. The analgesic activity was also investigated for its central and peripheral pharmacological actions using hot plate and tail immersion test and acetic acid -induced writhing test in mice respectively. The extract decreased the motor activity and exploratory behavior of mice in hole cross and open field test (p < 0.001). Moreover, the extract significantly maximized the duration of sleeping time when administered with thiopental sodium (p < 0.001). The extract, at the dose of 250 and 500 mg/kg, produced a significant (p < 0.05, p < 0.001) increase in pain threshold both in hotplate and tail immersion methods in a dose dependent manner. The results were comparable to the reference standard Nalbuphine. In acetic acid-induced writhing test, the extract (500 mg/kg) produced a maximum of 75.9% inhibition (p < 0.001) of writhing reaction compared to the reference drug Diclofenac-Na (10 mg/kg) (78.1%). These results suggest that the extract possesses strong CNS depressant and analgesic activity in mice.