γ-羟基丁酸对脑缺血再灌注后海马区γ-氨基丁酸及其A型受体α_1亚型的影响  

Effect of gamma hydroxybutyrate on the expressions of gamma-aminobytyric acid and its type A receptor alpha 1 in hippocampal CA1 of rats following focal cerebral ischemia reperfusion

作　　者：赵庆杰[1] 齐丹[1] 孟珊珊[1] 郜旭[1] 齐旭[1] 

机构地区：[1]哈尔滨医科大学附属第一医院神经内科,黑龙江省哈尔滨市150001

出　　处：《中国临床康复》2005年第45期37-39,共3页Chinese Journal of Clinical Rehabilitation

基　　金：黑龙江省科技攻关计划项目(GB02C137-02)~~

摘　　要：目的:观察γ-羟基丁酸对局部脑缺血再灌注大鼠海马CA1区γ-氨基丁酸及氨基丁酸A型受体α1亚型的影响,探讨其脑保护作用机制。方法:实验于2004-05-01/10-30在哈尔滨医科大学形态学实验中心完成。选用健康成年雄性Wistar大鼠60只,随机分为假手术组(n=10)、模型组(n=25)、治疗组(n=25),模型组和治疗组又各分5个时间点:即缺血1h再灌注1.5h,3h,6h,12h,24h,每个时间点5只。采用大脑中动脉拴线法,建立大鼠局部脑缺血再灌注模型,假手术组仅暴露颈内动脉,不阻断血流,24h后断头取脑。治疗组于再灌注前10min给予γ-羟基丁酸钠(GHBA)3.5mL/kg腹腔注射。模型组和治疗组分别于缺血1h再灌注1.5h,3h,6h,12h,24h,各取5只大鼠处死,断头取脑,置于40g/L多聚甲醛中固定,常规石蜡包埋,行5μm厚连续冠状切,用于苏木精-伊红染色及免疫组化检测。比较分析各组在不同时间点的γ-氨基丁酸能神经元及氨基丁酸A受体α1亚型阳性细胞数。结果:纳入动物共60只,手术过程及术后因麻醉过深、失血过多等原因,模型组死亡2只,治疗组死亡3只,进入结果分析11组共55只。①苏木精-伊红染色光镜观察结果:假手术组形态学改变不明显。模型组缺血区淡染,细胞数明显减少,但结构尚存,缺血周边细胞体积缩小,胞膜皱缩,核固缩深染,细胞间隙增大,海马区变化尤为显著。治疗组较模型组细胞数增多,细胞损害较轻。②海马CA1区γ-氨基丁酸能神经元免疫组化阳性细胞数:与假手术组比较,模型组与治疗组中缺血1h再灌注1.5h,3h,6h,12h,24h海马CA1区γ-氨基丁酸阳性神经元数量明显减少(P<0.05),治疗组缺血1h再灌注6h及以后各组均显著高于相应模型组(P<0.05)。③海马CA1区氨基丁酸A受体α1亚型免疫组化阳性细胞数:与假手术组比较,模型组、治疗组在中缺血1h再灌注12h及以后各组海马CA1区氨基丁酸A受体α1亚型免疫组化阳性细胞数明显�AIM： To observe the effect of gamma hydroxybutyric acid （GHB） on gammaaminobytyric acid （GABA） and its type A receptor α1 （GABAAα1R） subtypes in hippocampal CA1 of rats following focal cerebral ischemia reperfusion, and investigate the protective mechanism of GHB on ischemiareperfusion cerebral tissue. METHODS： The experiment was conducted in the Morphological Experimental Center, Hospital of Harbin Medical University from May to October 2004. Sixty male adult Wistar rats were randomly divided into 3 groups： sham-operated group （n=5）, model group （n=25） and treatment group （n=25）, and then the model group and treatment group were divided into 5 time points： isehemia for 1 hour and reperfusion for 1.5, 3, 6, 12 and 24 hours with 5 rats at each time point. Rat models of focal cerebral ischemia reperfusion were made by middle cerebral artery occlusion （MCAO）, and the rats in the sham-operated group were only treated by exposing internal carotid artery without line insertion and the brains were removed after 24 hours. The rats in the treatment group were abdominally injected with 3.5 mL/kg GHBA at 10 minutes before reperfusion. The brains were removed after the rats were killed at 1.5,3,6,12 and 24 hours following ischemia-reperfusion respectively, fixed with 4% parafonnaldehyde, routinely embedded in paraffin, and coronally sliced into slice 5μm of thickness for hematoxylin and eosin （HE） staining and immunohistochemieal staining. The changes of GABAergic neurons and GABAAα1R positive cells numbers were compared and analyzed at different times. RFSULTS： Sixty rats attended the experiment, and there were 2 and 3 dead rats caused by overdose of anesthesia or operation accident in control group and GHBA therapy group respectively. Fifty-five rats were brought in the analysis finally. （1）HE staining results： Morphology of the sham-operated group hardly changed, Ischemia area was stained weakly, neurons dramatically decreased and the structure still existed. The volum

关 键 词：脑缺血 基丁酸类 受体 GABA-A 再灌注损伤 

分 类 号：R743[医药卫生—神经病学与精神病学]