大鼠丘脑和下丘脑在线索诱导的海洛因复吸中的作用

摘要

目的 研究丘脑室旁核(PVT)和下丘脑外侧区(LH)在环境线索(CC)或条件性线索(CS)诱导的大鼠海洛因复吸中的作用.方法 SD大鼠进行生理盐水(对照组)或海洛因的自身给药训练,随后自然戒断,海洛因戒断大鼠随机分成模型组、CC组和CC+CS组;在戒断d 14,对照组和CC组均以环境线索诱导、CC+CS组以环境线索联合条件性线索诱导测定海洛因觅药行为的恢复,模型组不测定;利用免疫组化法检测所有组别大鼠PVT和LH脑区c-Fos蛋白的表达.结果 环境线索或条件性线索均能够诱导大鼠海洛因觅药行为的恢复;环境线索诱导大鼠海洛因觅药恢复时PVT脑区c-Fos免疫阳性表达明显增加(P<0.01);而LH脑区c-Fos免疫阳性表达在环境线索或条件性线索诱导大鼠海洛因觅药恢复时均明显增加(P<0.01).结论 PVT参与环境线索诱导的大鼠海洛因复吸过程,而LH同时参与环境线索或条件性线索诱导的大鼠海洛因复吸.%Aim To investigate the effects of paravent-ricular thalamus( PVT ) and lateral hypothalamus( LH ) on heroin relapse induced by drug-associated contextual cue ( CC ) or conditioned stimuli ( CS ). Methods Sprague-Dawley rats were trained to self-administer saline ( control group ) or heroin, then all rats were placed into home cages for abstinence. Heroin withdrawal rats were randomly divided into model group, CC group and CC + CS group. On 14 d after withdrawal , control group and CC group were evaluated for reinstatement of heroin seeking behaviors induced by CC, CC + CS group was measured for reinstatement of heroin seeking behaviors induced by CC plus CS. The c-Fos protein expression in PVT and LH of every group　was assayed by immunohistochemistry. Results The behavior results showed that rats emitted significantly heroin-seeking responses induced by CC or CS. The level of c-Fos immunoreactivity in PVT was increased during CC-induced reinstatement of heroin seeking ( P < 0. 01 ), while the expression level of c-Fos immunoreactivity in LH was both increased during CC or CS-induced reinstatement of heroin seeking ( P < 0. 01 ). Conclusion PVT is involved in CC-induced heroin relapse, while LH is involved in both CC or CS-in-duced heroin relapse.