Study of effect of Matricaria recutita extract on morphine withdrawal signs in the presence and following partial electrical lesion of paragigantocellularis nucleus in adult male rats

The sedative effect of Matricaria recutita (M. recutita) has been shown in some physiological phenomena. In this study the effect of M.recutita extract on the morphine withdrawal signs in the presence and partial electrical lesion of paragigantocellularis (PGi) nucleus in wistar rats were investigated. The animals were grouped randomly into intact, sham and PGi nucleus lesioned. Groups included the animals which received saline or M. recutita extract (25mg/kg). Lesion of PGi was induced by 2mA current for 3 seconds. For dependence induction, morphine sulfate was injected subcutaneous for a 7 days period. Naloxone (3mg/kg, I.P.) was injected to morphine withdrawal syndrome induction. Withdrawal signs such as climbing, jumping and Grooming was evaluated. The results showed that M. recutita extract in presence of PGi nucleus induced sedative effect significantly on climbing and Grooming behaviors, but it didnt have significant effect on jumping behavior. Lesion of PGi decreased climbing and Grooming behaviors significantly in comparison to sham group but it didnt have significant effect on jumping behavior. M. recutita extract in absence of PGi nucleus had sedative effect only on jumping behavior. It seems that PGi nucleus involves in some of the morphine withdrawal behaviors in dependent rats and M. recutita conducted its sedative effect in some of the behaviors through the attenuation of PGi nucleus activity or GABA-Bebzodiazepine receptors in the CNS.