Trifluoperazine attenuates naloxone-precipitated symptoms in morphine-dependent rats and mice / 中国药理学通报

ABSTRACT

AIM To investigate the effects of trifluoperazine on naloxone precipitated withdrawal symptoms in morphine dependent rats and mice, and its pharmacological mechanisms. METHODS\ Naloxone precipitated tests in morphine dependent rats and mice were used. RESULTS\ Trifluoperazine(2～20 mg?kg -1 ) dose dependently inhibited naloxone precipitated withdrawal jumping, wet dog shakes, paw tremor and weight loss in morphine dependent mice. With ip trifluoperazine (5～20 mg?kg -1 ), most of positive withdrawal symptoms, including jumping, wet dog shakes, defeacation, weight loss, teeth chattering, salivation, diarrhea, ptosis and irritating, induced by naloxone in morphine dependent rats were significantly reduced. Apomorphine (2～8 mg?kg -1 ), a mixed DA 1/DA 2 receptor agonist, did not affect inhibition of trifluoperazine on naloxone precipitated withdrawal symptoms in morphine dependent mice. However, nifedipine(5～20 mg?kg -1 ), a L type voltage sensitive calcium channel blocker, enhanced a pharmacological action of trifluoperazine against naloxone precipitated symptoms in morphine dependent mice. CONCLUSION\ Trifluoperazine attenuates naloxone precipitated withdrawal symptoms in morphine dependent rats and mice by inhibiting the activity of post receptor calmodulin, but it does not antagonizes DA 2 receptor, in central nervous system.