海洛因依赖大鼠VTA突触传递可塑性的研究  

A Study of VTA's Plasticity on Heroin-addicted Rats

作　　者：王宇晶[1] 牛晨[1] 潘贵书[1] 

机构地区：[1]遵义医学院生理学教研室,贵州563000

出　　处：《实验动物科学》2011年第6期13-17,共5页Laboratory Animal Science

基　　金：国家自然科学基金项目(No.30960109)

摘　　要：目的观察海洛因依赖大鼠中脑腹侧被盖区(vental tegment area,VTA)-伏隔核(nucleu accumbens,NAc)突触传递可塑性的变化。方法 SD雄性大鼠40只(180～220 g),随机分成对照组、海洛因依赖组(以下称依赖组)。按剂量递增原则,皮下注射海洛因,2次/d(9:00 am,16:00 pm),连续9 d(首日海洛因剂量3 mg/kg,逐日递增3 mg/kg),第10天用纳络酮催促戒断,确定大鼠海洛因成瘾模型成功建立。对照组按同样方式注射等量0.9%NaCl水溶液。海洛因依赖模型建立后,每天继续给海洛因维持量(27 mg/kg)。按大鼠脑立体定位图谱分别刺激VTA和NAc,并分别在NAc和VTA引导群体峰电位(Population spike,PS)(刺激参数:5 V,200 HZ,波宽300μs)。结果 1)建立的海洛因依赖模型组大鼠催促戒断症状的评分符合成瘾模型评分标准;2)海洛因依赖组分别高频刺激VTA和NAc,并分别在NAc和VTA引导长时程增强(long-term potentiation,LTP),其LTP的PS低于对照组(P<0.05)。结论 1)提示VTA和NAc之间存在着突触传递的通路;2)提示在海洛因的作用下,该通路的突触传递发生了可塑性的变化。Objective To examine the change of synaptic plasticity in VTA-NAc（Vental tegment area-Nucleu accumbens,VTA-NAc）circle in heroin-addicted rats.Methods Sprague-Dawley rats（180~220 g） were randomly divided into control group and heroin-treated group.Heroin were injected subcutaneously twice a day according to the principle of daily increasing dose to establish the model of heroin-dependence.Withdrawal was precipitated by administering the opioid antagonist naloxone to examine whether the heroin-addicted model was established.The control group was given equivalent volume of saline.For induction of LTP,high-frequency stimulations were applied to VTA and NAc,and population spike was recorded in vivo.Results 1）The withdrawal symptom is according with the scoring indications of the established heroin-addicted model of rats.2）The PS amplitude of LTP induced from NAc and VTA in heroin-addicted rats was significantly lower than control group（P 0.05）.Conclusion Heroin can influence synaptic plasticity in VTA-NAc circle in heroin-addicted rats.

关 键 词：海洛因依赖 中脑腹侧被盖区 伏隔核 长时程增强 群峰电位 

分 类 号：Q95-33[生物学—动物学]