EFFECTS OF PNS ON [Ca~(2+)]i IN HIPPOCAMPAL NEURONS OF MORPHINE WITHDRAWAL RATS

Objective To explore the possible mechanisms that panax notoginseng saponins(PNS) attenuate morphine withdrawal syndrome,the effects of PNS on cytoplasmic free calcium([Ca~(2+)]i) were observed in hippocampus of morphine withdrawal rats.Methods The models of morphine physical dependent and withdrawal rats were established by subcutaneous injection of morphine in gradually increasing doses and abdominal cavity injection of naloxone respectively.The rats were treated with PNS by intragastric administration at various doses,simultaneously with morphine.The models were confirmed by measuring the body weight loss and number of jumping.[Ca~(2+)]i in hippocampal neurons was measured using flow cytometry.Results ①PNS(100,200,400 mg/kg) could decrease the body weight loss and number of jumping in a dose dependent manner.②Chronic morphine treatment increased [Ca~(2+)]i concentration in hippocampal neurons.Naloxone could downregulated the markedly increased [Ca~(2+)]i in hippocampal neurons of morphine dependent rats.PNS could increase dose-dependently [Ca2+]i in hippocampal neurons of naloxone-precipitated withdrawal rats.Conclusion PNS could alleviate morphine withdrawal symptoms by regulating [Ca~(2+)]i of neurons.