吗啡依赖条件性位置厌恶大鼠伏隔核壳区5-羟色胺及其代谢产物5-羟吲哚乙酸水平检测分析

Detection and analysis of AcbSh 5-HT and its metabolite 5-HIAA levels in CPA rats

目的探讨吗啡依赖条件性位置厌恶大鼠伏隔核壳区5-羟色胺及其代谢产物5-羟吲噪乙酸水平的动态变化,揭示吗啡依赖戒断厌恶动机的神经生化机制。方法将60只雄性SD大鼠立体定位术后进入实验,按随机数字表法分为慢性吗啡注射+纳洛酮催瘾组(MN组)、慢性吗啡注射+生理盐水催瘾注射组(MS组)及慢性生理盐水注射+纳洛酮催瘾组(SN组);同时与条件性位置训练箱搭配建立条件性位置厌恶模型,采用在体微透析技术分别在术后第3d一第5d,条件性位置厌恶建立前后、条件性位置厌恶消退期及重建期7个时点收集伏隔核壳区细胞外液,采用高效液相色谱-电化学方法检测透析液中5-羟色胺及其代谢产物5-羟吲噪乙酸水平。结果条件性位置厌恶建立前,3组大鼠在伴药侧停留时间比较差异无统计学意义(P>0.05);条件性位置厌恶建立后,MN组大鼠在伴药侧停留时间显著短于MS组,SN组(P<0.01),条件性位置厌恶消退训练后,3组大鼠在伴药侧的停留时间比较差异无统计学意义(P>0.05),条件性位置厌恶重建后,MN组在伴药侧停留时间显著短于MS组,SN组(P<0.01)。吗啡注射后,MS组和MN组伏隔核壳区的5-羟色胺及5-羟吲噪乙酸水平显著高于SN组(P<0.05);条件性位置厌恶建立后,MN组5-羟色胺及5-羟明噪乙酸浓度显著低于MS和SN组(P<0.05);条件性位置厌恶消退后,MN组5-羟色胺及5-羟吲噪乙酸水平逐渐升高,与基线值比较差异无统计学意义(P>0.05);条件性位置厌恶重建后,MN组5-羟色胺及5-羟噪乙酸水平显著低于MS和SN组(P<0.05)。结论伏隔核壳区内5-羟色胺参与吗啡依赖戒断所致条件性位置厌恶相关中枢厌恶动机,可能是阿片依赖的临床治疗的潜在靶点之一。

Objective To investigate the dynamic changes of AcbSh 5-HT and its metabolite 5-HIAA levels in CPA rats,and to reveal the neurochemical mechanism of morphine-dependent withdrawal aversion.Methods 69 male SD rats were randomly divided into the MN group,MS group,SN group after stereotactic surgery.Establish a conditional position aversion model with a conditional position training box,extracorporeal fluid of nucleus accumbens was collected by in vivo microdialysis technique on the 3rd to 5th day after surgery,before and after the establishment of conditional aversion,conditional aversion and regression.High performance liquid chromatography-electrochemical method was used to detect the level of 5-HT and its metabolite 5-HIAA in dialysate.Results Before the establishment of conditioned place aver-sion,there was no significant difference in the residence time of the three groups of rats on the concomitant side(P>0.05).After the establishment of conditioned place aversion,the residence time of the rats in the MN group was significantly shorter than that in the MS group and the SN group(P<0.01).After CPA regression training,there was no significant difference in the residence time of the three groups of rats on the concomitant side(P>0.05).After CPA reconstruction,the staying time of the MN group on the concomitant side was significantly shorter than that of the MS group and the SN group(P<0.01).After morphine injection,the levels of 5-HT and 5-HIAA in the nucleus accumbens of MS group and MN group were significantly higher thanthose in SN group(P<0.05).After CPA was established,the concentration of 5-HT and 5-HIAA in MN group was significantly lower than that in MS and SN group(P<0.05).After CPA subsided,the levels of 5-HT and 5-HIAA in MN group gradually increased,and there was no significant difference compared with baseline(P>0.05).After CPA reconstruction,the levels of serotonin and 5-hydroxyindoleacetic acid in the MN group were significantly lower than those in the MS and SN groups(P<0.05).Conclusion The AcbSh 5-HT level of rats may participate in morphine addiction withdrawal-induced aversion motivation,and is probably one of the clinical treatment of opioid addiction potential targets.