Zhu Zai-Man, Hua Tian-Miao, Zhou Hong-Ming, Pan Qun-Wan, Li Jing, Li Min
Zhongguo Ying Yong Sheng Li Xue Za Zhi. 2014 Jul;30(4):368-72.
To analyze the electrical activity property changes in nucleus accumbens (NAc) of heroin-induced conditioned place preference (CPP) rats during different stages of heroin dependence and to explore NAc's roles in the formation of drug dependence.
Recording electrodes were bilaterally embedded into the NAcs of rats with the aid of stereotaxic apparatus, followed by establishment of heroin-dependent rat model. The NAc electrical activity during 3 different stages of heroin dependence, including heroin pre-exposure, immediate post-exposure and heroin withdrawal, were respectively recorded using EEG wireless telemetry techniques. The frequency distribution (ranging from 0.5 to 30 Hz) and the amplitude of NAc electrical activity were analyzed and measured.
Heroin-dependent rat models were successfully established and their withdrawal symptoms were evident. All rats showed a conditioned place preference (CPP) for the white box after 5-10 days of heroin-exposure, and displayed a maximum withdrawal symptoms on 2d after heroin- withdrawal. During all statges of heroin-dependence, the NAc electrical activity contained the highest proportion of delta rhythm and the lowest proportion of alpha2 rhythm. The discharge frequence band was similar across different stages. There was a significantly increased ratio of low-frequency discharges (delta rhythm) and decreased ratio of high-frequency discharges (beta rhythm) in NAc of rats during the immediate post- heroin exposure stage when compared with that during pre-exposure and heroin withdrawal stages. During the withdrawal stage, the ratio of at rhythm was significantly lower than during pre- and post-heroin exposure stages (P < 0.01). Further, the mean discharge amplitude in NAcs during immediate post-exposure and withdrawal stages was significantly increased relative to pre-exposure stage. However, the mean discharge amplitude during heroin withdrawal stage was significantly lower than during immediate post-exposure stage.
The electrical activity properties in rat NAcs showed a significant change during different stages of heroin-dependence, which suggested that neuronal activities in NAcs might contribute to the modulation of drug-dependence.
分析海洛因诱导的条件性位置偏爱（CPP）大鼠在海洛因依赖不同阶段伏隔核（NAc）电活动特性的变化，探讨NAc在药物依赖形成中的作用。
借助立体定位仪将记录电极双侧植入大鼠NAc，随后建立海洛因依赖大鼠模型。采用脑电图无线遥测技术分别记录海洛因依赖3个不同阶段（海洛因预暴露、暴露后即刻和海洛因戒断）的NAc电活动。分析并测量NAc电活动的频率分布（范围为0.5至30Hz）和幅度。
成功建立海洛因依赖大鼠模型，其戒断症状明显。所有大鼠在海洛因暴露5 - 10天后均对白色盒子表现出条件性位置偏爱（CPP），并在海洛因戒断后第2天表现出最大戒断症状。在海洛因依赖的所有阶段，NAc电活动中δ节律所占比例最高，α2节律所占比例最低。不同阶段的放电频率带相似。与预暴露和海洛因戒断阶段相比，海洛因暴露后即刻大鼠NAc中低频放电（δ节律）比例显著增加，高频放电（β节律）比例降低。在戒断阶段，α节律比例显著低于海洛因暴露前和暴露后阶段（P < 0.01）。此外，暴露后即刻和戒断阶段NAc的平均放电幅度相对于预暴露阶段显著增加。然而，海洛因戒断阶段的平均放电幅度显著低于暴露后即刻阶段。
大鼠NAc的电活动特性在海洛因依赖的不同阶段表现出显著变化，这表明NAc中的神经元活动可能参与药物依赖的调节。
