脑啡肽乙酸酯对大鼠急性全脑缺血－再灌注后海马区神经元保护的机制研究  

Neuroprotective effect of DADLE on the neurons in rat brain hippocampus with acute global cerebral ischemia -reperfusion injury

作　　者：梁庆[1] 梁子敬[1] 林俊敏[1] 郭伟[1] 郭锻强[1] 韩洁韵[1] 黄伟青[1] 邝素华[2] 杨志华[3] 

机构地区：[1]广州医科大学附属第一医院急诊科,广东广州510120 [2]广州医科大学附属第一医院心脏外科,广东广州510120 [3]广州医科大学附属第一医院神经内科,广东广州510120

出　　处：《中国急救医学》2015年第6期539-543,I0002,共6页Chinese Journal of Critical Care Medicine

基　　金：广州市医药卫生科技项目（201102A213152）；2012年广东省临床重点专科基金

摘　　要：目的：研究脑啡肽乙酸酯（ DADLE）是否通过调控胞外信号调控激酶（ ERK）信号转导通路而抑制大鼠急性全脑缺血－再灌注后海马区神经细胞凋亡。方法健康雌性SD大鼠50只（180～220 g）随机分为五组，建立大鼠急性全脑缺血－再灌注模型：假手术组（ Sham组，n＝10），只行手术分离血管，不予结扎血管及再灌注；缺血－再灌注组（I／R组，n＝10），缺血15 min，再灌注120 min；DADLE＋PD98059组（DA＋PD组，n＝10），缺血15 min后再灌注开始前静脉注射DADLE（3 mg／kg）及PD98059（0．3 mg／kg），然后行再灌注120 min； PD98059组（PD组，n＝10），缺血15 min后再灌注开始前静脉注射PD98059（0．3 mg／kg）；DADLE处理组（DA组，n＝10），缺血15 min后再灌注开始前静脉注射DADLE（3 mg／kg），然后行再灌注120 min。 HE染色观察各组海马CA1区神经元病理变化情况，TUNEL法检测大鼠海马凋亡细胞，Western blot检测脑组织磷酸化ERK1／2（P－ERK1／2）的表达状况。结果 HE染色显示，I／R组、DA＋PD组、PD组、DA组较Sham组正常神经元细胞计数显著减少（P＜0．01）；DA组神经元的损伤、脱失、细胞肿胀均较I／R组轻，正常神经元细胞计数较I／R组显著增多（P＜0．01）；PD组、DA＋PD组及I／R组正常神经元细胞计数组间两两比较差异无统计学意义。 TUNEL法检测显示，I／R组、DA＋PD组、PD组、DA组大鼠海马CA1区神经细胞凋亡指数均较Sham组显著升高（P＜0．01）；与I／R组比较，DA＋PD组及DA组凋亡指数显著下降（P＜0．01），PD组凋亡指数则升高（P＜0．05）；DA＋PD组、PD组及DA组组间两两比较差异有统计学意义（ P＜0．01）。Western blot检测显示，I／R组（0．69±0．07）、DA＋PD组（0．59±0．03）及DA组（0．83±0．06）的P－ERK1／2表达较Sham组（0．42±0．06）增多（P＜0．01），而PD组（0．41±0．05）则无显著�Objective To investigate whether DADLE could affect rat brain hippocampus neuronal apoptosis after acute global cerebral ischemia-reperfusion injury by regulating ERK signaling pathway.Methods Fifty female Sprague-Dawley rats （180 ~220 g） were randomly divided into 5 groups：sham group （Sham, n=10） exposed bilateral common artery but without occlusion;ischemia/reperfusion group （ I/R, n =10 ） was induced by bilateral common artery occlusion combined with hypotension for 15 min global ischemia followed by 120 min reperfusion; DADLE ＋PD98059 group （DA＋PD, n=10）, DADLE （3 mg/kg, iv） and PD98059 （0.3 mg/kg, iv） was applied through external jugular vein before reperfusion; PD98059 group （PD, n=10）, PD98059 （0.3 mg/kg, iv） were applied through external jugular vein before reperfusion; DADLE group： DADLE （3 mg/kg, iv） was applied through external jugular vein before reperfusion. Neuropathological changes in rat hippocampus CA1 area were observed by Hernatoxylin-Eosin （ H-E） staining.Apoptotic cells in rat hippocampus were detected by TUNEL method, and the expression of phosphorylated ERK （ P-ERK） in rat brain tissue was assessed by immunoblotting.Results H -E staining demonstrated that the normal neurons in hippocampal CA1 area were significantly decreased in I/R, DA＋PD, PD and DA group compared with that in Sham group （P〈0.01）;and in DA group when compared with I/R group the normal neurons was remarkably increased （P〈0.01） with less neuronal damage, demyelination, cell swelling.But there were no significant difference of normal neurons counting among the PD, DA＋PD and DADLE groups.TUNEL assay showed I/R group, DA ＋PD group, PD group, DA rat hippocampal CA1 neuronal apoptosis index was significantly higher than that in the Sham group （ P〈0.01）;compared with I/R group, apoptotic index was significantly decreased （P〈0.01） in DA＋PD and and DA group, but was increased （P〈0.05） in PD group;there were significant difference （P〈0.01）

关 键 词：脑啡肽乙酸酯( DADLE) 全脑 缺血-再灌注 胞内细胞外信号调节激酶1/2(ERK1/2) 神经细胞凋亡 大鼠 

分 类 号：R743.3[医药卫生—神经病学与精神病学]