Effects of Bonium persicum B.Fedtsch fruit ethanolic extract on morphine tolerance and dependence in adult male NMRI mice

Morphine causes the development of dependence, which limits its usage for chronic pain. Morphine dependence is a compulsive pattern of drug seeking and drug taking, resulting from the positive reinforcement of the rewarding effects of drug taking and the negative reinforcement of withdrawal syndrome that accompanies the cessation of drug taking. The objective of this research was to investigate the effects of caraway (Bonium persicum B.Fedtsch) ethanolic extract on acquisition and expression of morphine tolerance and dependence in mice.

In this experimental study, hot-plate test was used to survey morphine analgesic tolerance. Morphine was injected (2.5, 5, 10, 20, 40 mg/kg, i.p.) twice daily for 7 days, except in 8th day in which morphine was administrated at a single dose (50 mg/kg, i.p.). The extract (300, 400, 500 mg/kg, i.p.) was injected daily for 8 days. Also, Naloxone was injected (10 mg/kg, i.p.) 5 hours after the final dose of morphine and the withdrawal signs including jumping, abdominal contraction, teeth chattering, grooming, diarrhea, and ptosis were recorded during a period of 30 minutes.

Caraway extract significantly attenuated both development and expression of morphine dependence. It significantly reduced jumping, abdominal contraction, teeth chattering, grooming, diarrhea, and ptosis.

These findings indicate effectiveness of caraway extract for management of morphine tolerance. Results of this study indicate that the plant contained component(s) that alleviate morphine withdrawal syndrome.