Interaction of morphine with progesterone in strychnine- induced convulsion

Convulsion is a common disorder of nervous system and many studies have been done about it. Anticonvulsant effects of progesterone and morphine have been shown by some studies. In present study, the interaction between progesterone and morphine has been investigated in strychnine- induced convulsion. To ensure the elimination of sex hormones cyclic changes effect in the body mice were ovariectomized. After two weeks of recovery, they were divided into nine groups (6-8 mouse in each group). Convulsion model was induced by subcutaneously injection of strychnine. All drugs were intraperitoneally injected except strychnine. The studied groups included: groups receiving 1- normal saline (5ml/kg) 2- Morphine (1mg/kg) 3- Morphine (2mg/kg) 4- Morphine (3mg/kg) 5– almond oil (5ml/kg) 6 - progesterone (25mg/kg) 7 - progesterone (50mg/kg) 8- morphine (3mg/kg)+ progesterone (25mg/kg) 9- morphine (3mg/kg)+ progesterone (50mg/kg). Onset of convulsion and time of death were determined. The results showed that the morphine has no effect on anticonvulsant effect of high dose of progesterone but it reduced the anticonvulsant effect of low dose progesterone. reduced anticonvulsant effect of low dose progesterone by morphine seems to be a result of interaction of the morphine with neurotransmitters system such as GABAregic system.