Effects of Otostegia persica (Burm.) Boiss on morphine withdrawal syndrome in mice

Effect of Otostegia persica on naloxone-induced morphine withdrawal syndrome was studied in male mice. Dependence was induced using daily subcutaneous injections of morphine for three days. Morphine was injected to mice at doses of 30 and 45mg/kg on day 1 and 60 and 90mg/kg on day 2 (8:00 am and 6:00 pm). On day 3, morphine (90mg/kg) was injected 1h before oral administration and 1.5h before intraperitoneal (i.p.) injection of hydroalcoholic and hexane extracts of the plant. Naloxone was injected (5mg/kg, i.p.) 2h after the final dose of morphine and the withdrawal signs including jumping, rearing, diarrhoea, piloerection, tremor and ptosis were recorded during a period of 30 minutes. While oral and i.p. administration of hydroalcoholic extract reduced the number of jumping and rearing, the hexane extract could not exert any significant change. Also the hydroalcoholic extract (1500mg/kg) significantly (p<0.05) reduced diarrhoea, piloerection, tremor and ptosis. The hexane extract only significantly (p<0.05) inhibited diarrhoea. Results of this study indicated that the extract of Otostegia persica contained component(s) that alleviate morphine withdrawal syndrome and the responsible constituent(s) is(are) found in polar fraction since the hexane extract had only a negligible effect.