5-HT1A受体拮抗剂对七氟烷致老年认知功能障碍模型大鼠突触可塑性的作用及其机制  

Effects of the 5-HT1A receptor antagonist on synaptic plasticity in sevoflurane-induced cognitive dysfunction in aged rats and its mechanism

作　　者：邹佳芮 陈克研 张振[1] ZOU Jiarui;CHEN Keyan;ZHANG Zhen(Department of Anesthesiology,Central Hospital Affiliated to Dalian University of Technology,Dalian 116024,China;Department of Experimental Animal,China Medical University,Shenyang 110122,China)

机构地区：[1]大连理工大学附属中心医院麻醉科,辽宁大连116024 [2]中国医科大学实验动物部,沈阳110122

出　　处：《中国医科大学学报》2024年第1期60-66,74,共8页Journal of China Medical University

基　　金：辽宁省自然科学基金(2022-MS-180)。

摘　　要：目的探讨5-HT1A受体拮抗剂对七氟烷致老年认知功能障碍模型大鼠突触可塑性的作用及其机制。方法将30只18月龄Sprague-Dawley大鼠随机分为对照组、模型组以及治疗组。模型组吸入50%空气、氧气混合物(2 L/min)和2%七氟烷4 h后左侧脑室给予生理盐水(5μL),治疗组在吸入50%空气、氧气混合物(2 L/min)和2%七氟烷4 h后左侧脑室给予5-HT1A受体拮抗剂(3μg),对照组仅吸入50%空气、氧气混合物(2 L/min)4 h。水迷宫法检测各组大鼠的学习记忆能力;HE染色法观察各组大鼠海马组织病理变化情况;尼氏染色和高尔基染色观察海马区神经元和突触的病理形态变化;免疫荧光法检测MeCP2、p250GAP、PSD-95、GAP-43与Syn蛋白表达;实时荧光定量PCR检测PKA、CREB1、BDNF mRNA表达水平;Western blotting检测PKA、CREB1、p-CREB1、BDNF蛋白表达水平。结果与对照组比较,模型组大鼠逃避潜伏期显著延长,穿越平台次数显著减少(P<0.05);与模型组比较,治疗组大鼠逃避潜伏期显著缩短,穿越平台次数明显增多(P<0.05)。HE、尼氏和高尔基染色显示,与对照组比较,模型组大鼠海马神经元形态不规则,排列松散,周围组织间隙扩大,细胞核固缩深染,部分神经元内尼氏体减少,树突分支数量以及树突棘密度明显减少;与模型组比较,治疗组大鼠海马神经元形态规则,结构相对完整,排列均匀,神经元内尼氏体数量增多,树突分支数量及树突棘密度显著增加。与对照组比较,模型组大鼠脑组织MeCP2、PSD-95、GAP-43、Syn蛋白,PKA、CREB1、BDNF mRNA和蛋白表达明显减少(P<0.05),p250GAP蛋白表达明显增加(P<0.05)。与模型组比较,治疗组MeCP2、PSD-95、GAP-43、Syn蛋白,PKA、CREB1、BDNF mRNA和蛋白表达明显增加(P<0.05),p250GAP蛋白表达明显减少(P<0.05)。结论5-HT1A受体拮抗剂通过激活CREB/BDNF通路,增强PSD-95、GAP-43、Syn表达,促进突触重塑,保护大鼠海马神经元细胞,从而改善七�Objective To investigate the effect of the 5-HT1A receptor antagonist on synaptic plasticity in flurane-induced cognitive dysfunction in aged rats.Methods Thirty 18-month-old Sprague-Dawley rats were randomly divided into control,model,and drug groups.The model group inhaled a 50%oxygen gas mixture(2 L/min)and 2%sevoflurane and were then treated with 5μL 0.9%NaCl;the drug group inhaled a 50%oxygen mixture(2 L/min)and 2%sevoflurane for 4 h and then the 5-HT1A receptor antagonist(3μg)was injected into the left ventricles of the rats;and the control group inhaled a 50%oxygen mixture(2 L/min)for 4 h.The water maze method was used to assess the learning memory of the rats and histopathological changes in the rat hippocampus were examined by HE staining.Nissl and Golgi staining were used to identify any changes to the neurons and synapses in hippocampal tissue.The MeCP2,p250GAP,PSD-95,GAP-43,and Syn expression levels were determined by immunofluorescence assay and the PKA,CREB1,and BDNF mRNA levels were determined using real-time PCR.Western blotting was performed to determine the PKA,CREB1,p-CREB1,and BDNF expression levels.Results The water maze data showed that the escape latency was significantly prolonged in the model group compared to the control group and,after treatment with the 5-HT1A receptor antagonist,the escape latency significantly decreased in the drug group compared to that of the model group(P<0.05).Moreover,the number of platform crossings was significantly lower in the model group than in the control group,but the number of platform crossings in the drug group was significantly higher than that in the model group(P<0.05).Compared to the control group,the hippocampal neurons in the model group had irregular morphology,loosely arranged and enlarged surrounding tissue gaps,deeply stained nuclei,a reduced number of Nissl bodies in the neurons,and a significantly reduced dendritic spine density and number of branches.After treatment with the 5-HT1A receptor antagonist,the hippocampal neurons in the drug

关 键 词：5-HT1A受体拮抗剂 CREB/BDNF通路 突触可塑性 认知功能障碍 

分 类 号：R614[医药卫生—麻醉学]