The role of endogenous no in the analgesic activity of morphine and mepyramine

In this study, the role of endogenous nltrlc oxide in % antinociceptive activity of morphine and mepyramine has been assessd by p-BQ induced writhing algesla model in mice. The effects of morphine (0.13 mg.kg- 1 ), mepyramine (5.6 mg.kg- 1 ) , L-arginine (50 mg.kg- 1nd L-N-Monomethylarginine (50 mg.kg-1 )n the abdomlnal constriction of mice induced by p-BQ were evaluated by single s. c. admin.1 str ati ons and, as double and tritlated combinations. Prosents results generallay Indlcate that, L- arginine potantiates the % antinociceptive activity of both morphine and mepyramine. In additlon to that, L-NMMA Inhibitis the antinociceptive activity of both compounds The overall results show that there is an evidance of endogenous NO plays a role in the antinociceptive activity of morphine and mepyramine. The effects of morphine(0,13 mg.kg-1) ,mepyramine ( 5,6 mg.kg-1),in the abdominal constriction of mice induced by p-BQ were evaluated by single s.c.admin.1 strations and as double and tritlated combinations. Present results generally indicate that, L-arginine potantiates the % antinociceptive activity of both morphine and mepyramine.In addition to that, L-NMMA inhibits the antinociceptive activity of both compounds. The overall results show that there is an evidence of endogenous NO plays a role in the antinociceptive activity of morphine and mepyramine.