孕酮对大鼠吗啡位置偏爱相关脑区中β-内啡肽水平的影响  

Effects of Progesterone on Morphine-induced Conditioned Place Preference and Levels of β-endorphin in Rat Brain

作　　者：于动震[1] 吴红海[1] 侯艳宁[1] 

机构地区：[1]解放军白求恩国际和平医院药学部

出　　处：《华北国防医药》2008年第2期5-7,共3页Medical Journal of Beijing Military Region

基　　金：河北省自然科学基金资助项目(C2005000834)

摘　　要：目的:观察孕酮对吗啡所致奖赏效应及相关脑区中β-内啡肽(β-EP)水平的影响。方法:将40只SD大鼠随机分为生理盐水对照(NS)组、吗啡组、孕酮组和孕酮+吗啡组,上午NS组和孕酮组皮下给予环糊精和孕酮15mg/kg,10min后腹腔给予生理盐水5mg/kg,吗啡组和孕酮+吗啡组皮下给予环糊精和孕酮15mg/kg,10min后腹腔给予吗啡5mg/kg,放入白室训练。下午各组动物均皮下和腹腔给予等量的环糊精和生理盐水,放入黑室训练。建立吗啡条件性位置偏爱(CPP)模型,采用放射免疫法测定大鼠不同脑区中β-EP含量。结果:与NS组比较,吗啡组产生稳定的CPP效应(P<0.01),孕酮和孕酮+吗啡组均未产生CPP效应。与NS组比较,CPP形成时,吗啡组大鼠下丘脑、海马和额叶皮质中β-EP水平显著降低(P<0.05,P<0.01和P<0.05)。与吗啡组比较,孕酮+吗啡组大鼠下丘脑中β-EP水平显著升高(P<0.01),而其他脑区内无明显变化(P>0.05)。结论:孕酮可有效抑制吗啡CPP效应,其机制可能与逆转吗啡诱导的下丘脑中β-EP水平有关。Objective：The aim of the study was to investigate the effects of progesterone on morphine rewarding effect and levels of β-endorphin（β-EP） in rat brain. Methods：40 male SD rats were designated to 4 groups randomly with 10 in each,including saline control group, morphine group,progesterone group and progesterone plus morphine group. In the morning,the group of saline and progesterone had hypodermic injection of cyclodextrin and progesterone of 15 mg/kg, 10 min later, had intraperitoneal injection of saline of 5 mg/kg. The morphine and grogesterone plus morphine group had hypodermic injection of cyclodextrin and progesterone of 15 mg/kg, 10 min later,had intraperitoneal injection of morphine 5 mg/kg. All rats were put into the white room for training. And in the afternoon,all rats had hypodermic injection of cyclodextrin and intraperitoneal injection of saline of the same dose, and all were put into the black room for the same training. Conditioned place preference（CPP） test was used to investigate the morphine rewarding effect,and radioimmunoassay（RIA） was established to determine the levels of β-EP in rat brain. Results：Compared with NS control group,5 mg/kg morphine successfully induced the formation of CPP（ P 〈 0. 01 ）. 15 mg/kg progesterone was not able to induce CPP effect itself,but was able to restrain the morphine CPP effect. Compared with NS control group, the levels of β-EP following morphine administration decreased significantly in hypothalamus, hippocampus and frontal cortex（ P 〈0.05,P 〈 0.01 and P 〈 0. 05 ）. Compared with morphine group, the levels of β-EP increased significantly by co-administration with 15 mg/kg dose of progesterone in hypothalamus （P 〈 0.01 ）. Conclusion：It is estimated that progesterone can attenuate morphine induced CPP effectively. The effect of progesterone on morphine-induced CPP can be conduced through its action on β-EP.

关 键 词：孕酮 吗啡 条件性位置偏爱 β-内啡肽 

分 类 号：R964[医药卫生—药理学] R349.32[医药卫生—药学]