环境激发吗啡CPP复燃大鼠杏仁核PSD-95的表达

Expression of PSD-95 in amygdaloid body with morphine conditioned place preference after environment induced reinstatement in rats

目的检测吗啡条件性位置偏爱(conditioned place preference,CPP)复燃大鼠杏仁核突触后致密质-95(PSD-95)的表达,探讨其在吗啡成瘾中对记忆的影响。方法 SD大鼠32只,随机分为吗啡依赖组(MD)、吗啡CPP消退组(ME)、环境激发组(MR)和对照组(N)。建立吗啡CPP模型,自然消退后,通过环境诱发CPP复燃,应用免疫组化和RT-PCR方法,观察检测激发组大鼠杏仁核PSD-95蛋白和mRNA表达,并与依赖组、消退组、对照组进行比较。结果吗啡CPP环境激发组、吗啡CPP消退组和对照组比较,杏仁核PSD-95的表达明显增加,具有高度显著性差异(P<0.01);吗啡依赖组与对照组比较,PSD-95的表达明显降低,具有高度显著性差异(P<0.01)。结论吗啡CPP环境激发组大鼠杏仁核PSD-95表达明显增高,PSD-95可能参与了成瘾记忆。

Objective To investigate expression of postsynaptic density protein-95 （PSD-95） in amygdaloid body with morphine conditioned place preference（CPP） after environment induced reinstatement and to evaluate the influence of PSD-95 on addiction memory in rats. Methods Thirty-two rats were randomly divided into 4 groups（n =8 in each group） ： group MD,group ME, group MR, group N. Rat CPP model was established by intraperitoneal injection of morphine. Reinstatement was induced by environment after extinction of CPP. PSD-95 protein and mRNA in amygdaloid body were detected by immunohistochemical and RT-PCR assays. Results Compared with control group, the expression of PSD-95 in amygdaloid body was significantly increased in reinstatement and extinction group by morphine CPP （P 〈 0.01 ）. Expression of PSD-95 was also significantly up-regulated in reinstatement group as compared with extinction group （P 〈 0. 01）. In morphine dependent group, expression of PSD-95 was down-regulated in comparison with control group （P 〈0.01 ）. Conclusion The expression of PSD-95 in amygdaloid body is significantly increased by environment induced reinstatement in rats, suggesting that PSD-95 may play a role in addiction memory.