CAJ | 학술논문

背景:核因子κB是一种重要的转录因子,激活后能促进许多靶基因转录.目的:研究核因子κB在局部脑缺血及再灌注中的表达及N-乙酰半胱氨酸预处理的影响.设计:随机分组设计、动物实验.单位:哈尔滨医科大学第二临床学院神经内科.材料:实验于2004-01/05在哈尔滨医科大学动物实验中心及病理实验室完成.选择健康雄性Wister大鼠99只,随机分3组,假手术组11只,生理盐水对照组44只,N-乙酰半胱氨酸组44只.方法:3组大鼠采用Longa等改良线栓法制备大鼠局灶性脑缺血模型.将头端加热成0.26mm直径的光滑圆球的尼龙线经颈总动脉近分叉处切口插入,扎紧颈总动脉备线,打开颈内动脉上的微动脉夹,尼龙线进入颈内动脉,N-乙酰半胱氨酸组和生理盐水对照组插入长度由颈内动脉和颈外动脉分叉部计约(18.5±0.5)mm,阻断大脑中动脉血供,假手术组插入深度＜15 mm,大脑中动脉血供正常.N-乙酰半胱氨酸组于缺血前30min腹腔注射N-乙酰半胱氨酸(150mg/kg),生理盐水对照组于缺血前30 min注射等体积生理盐水.生理盐水对照组和N-乙酰半胱氨酸组于缺血6,24 h,缺血6,24 h再灌注1 h时间点将大鼠断颈处死,每次11只.应用免疫组织化学法观察脑组织核因子κB的表达情况,红四氯氮唑染色测定各组大鼠脑梗死体积百分比,脱氧核糖核苷酸末端转移酶介导的缺口末端标记法检测脑组织细胞凋亡.主要观察指标:各组大鼠脑梗死体积百分比,核因子κB p65结合活性,凋亡细胞.结果:纳入动物99只,均进入结果分析.①缺血6 h及24 h再灌注1 hN-乙酰半胱氨酸组梗死体积百分比分别为(8.39±2.54)%,(24.54±6.02)%,相应生理盐水对照组为(15.50±4.18)%,(32.22±3.99)%.缺血24 h各组较缺血6 h各组梗死灶增大,使用N-乙酰半胱氨酸组较生理盐水对照组梗死体积明显缩小(P＜0.01).②缺血及再灌注后核因子κBp65明显从胞质转移到胞核.缺血6 h及24 h再灌注N-乙酰半胱氨酸组p65阳性细胞率分别为(0.462±0.022)%,(0.452±0.015)%,与相应生理盐水对照组[(0.563±0.028)%,(0.554±0.013)%]比较表达减少(P＜0.01).③N-乙酰半胱氨酸预处理较生理盐水预处理凋亡细胞减少.结论:局灶脑缺血及再灌注能使核因子κBp65活化,参与脑缺血及再灌注损伤.N-乙酰半胱氨酸可抑制p65表达,减轻神经损伤,具有脑保护作用. 揹景:覈因子κB是一種重要的轉錄因子,激活後能促進許多靶基因轉錄.目的:研究覈因子κB在跼部腦缺血及再灌註中的錶達及N-乙酰半胱氨痠預處理的影響.設計:隨機分組設計、動物實驗.單位:哈爾濱醫科大學第二臨床學院神經內科.材料:實驗于2004-01/05在哈爾濱醫科大學動物實驗中心及病理實驗室完成.選擇健康雄性Wister大鼠99隻,隨機分3組,假手術組11隻,生理鹽水對照組44隻,N-乙酰半胱氨痠組44隻.方法:3組大鼠採用Longa等改良線栓法製備大鼠跼竈性腦缺血模型.將頭耑加熱成0.26mm直徑的光滑圓毬的尼龍線經頸總動脈近分扠處切口插入,扎緊頸總動脈備線,打開頸內動脈上的微動脈夾,尼龍線進入頸內動脈,N-乙酰半胱氨痠組和生理鹽水對照組插入長度由頸內動脈和頸外動脈分扠部計約(18.5±0.5)mm,阻斷大腦中動脈血供,假手術組插入深度＜15 mm,大腦中動脈血供正常.N-乙酰半胱氨痠組于缺血前30min腹腔註射N-乙酰半胱氨痠(150mg/kg),生理鹽水對照組于缺血前30 min註射等體積生理鹽水.生理鹽水對照組和N-乙酰半胱氨痠組于缺血6,24 h,缺血6,24 h再灌註1 h時間點將大鼠斷頸處死,每次11隻.應用免疫組織化學法觀察腦組織覈因子κB的錶達情況,紅四氯氮唑染色測定各組大鼠腦梗死體積百分比,脫氧覈糖覈苷痠末耑轉移酶介導的缺口末耑標記法檢測腦組織細胞凋亡.主要觀察指標:各組大鼠腦梗死體積百分比,覈因子κB p65結閤活性,凋亡細胞.結果:納入動物99隻,均進入結果分析.①缺血6 h及24 h再灌註1 hN-乙酰半胱氨痠組梗死體積百分比分彆為(8.39±2.54)%,(24.54±6.02)%,相應生理鹽水對照組為(15.50±4.18)%,(32.22±3.99)%.缺血24 h各組較缺血6 h各組梗死竈增大,使用N-乙酰半胱氨痠組較生理鹽水對照組梗死體積明顯縮小(P＜0.01).②缺血及再灌註後覈因子κBp65明顯從胞質轉移到胞覈.缺血6 h及24 h再灌註N-乙酰半胱氨痠組p65暘性細胞率分彆為(0.462±0.022)%,(0.452±0.015)%,與相應生理鹽水對照組[(0.563±0.028)%,(0.554±0.013)%]比較錶達減少(P＜0.01).③N-乙酰半胱氨痠預處理較生理鹽水預處理凋亡細胞減少.結論:跼竈腦缺血及再灌註能使覈因子κBp65活化,參與腦缺血及再灌註損傷.N-乙酰半胱氨痠可抑製p65錶達,減輕神經損傷,具有腦保護作用.
배경:핵인자κB시일충중요적전록인자,격활후능촉진허다파기인전록.목적:연구핵인자κB재국부뇌결혈급재관주중적표체급N-을선반광안산예처리적영향.설계:수궤분조설계、동물실험.단위:합이빈의과대학제이림상학원신경내과.재료:실험우2004-01/05재합이빈의과대학동물실험중심급병리실험실완성.선택건강웅성Wister대서99지,수궤분3조,가수술조11지,생리염수대조조44지,N-을선반광안산조44지.방법:3조대서채용Longa등개량선전법제비대서국조성뇌결혈모형.장두단가열성0.26mm직경적광활원구적니룡선경경총동맥근분차처절구삽입,찰긴경총동맥비선,타개경내동맥상적미동맥협,니룡선진입경내동맥,N-을선반광안산조화생리염수대조조삽입장도유경내동맥화경외동맥분차부계약(18.5±0.5)mm,조단대뇌중동맥혈공,가수술조삽입심도＜15 mm,대뇌중동맥혈공정상.N-을선반광안산조우결혈전30min복강주사N-을선반광안산(150mg/kg),생리염수대조조우결혈전30 min주사등체적생리염수.생리염수대조조화N-을선반광안산조우결혈6,24 h,결혈6,24 h재관주1 h시간점장대서단경처사,매차11지.응용면역조직화학법관찰뇌조직핵인자κB적표체정황,홍사록담서염색측정각조대서뇌경사체적백분비,탈양핵당핵감산말단전이매개도적결구말단표기법검측뇌조직세포조망.주요관찰지표:각조대서뇌경사체적백분비,핵인자κB p65결합활성,조망세포.결과:납입동물99지,균진입결과분석.①결혈6 h급24 h재관주1 hN-을선반광안산조경사체적백분비분별위(8.39±2.54)%,(24.54±6.02)%,상응생리염수대조조위(15.50±4.18)%,(32.22±3.99)%.결혈24 h각조교결혈6 h각조경사조증대,사용N-을선반광안산조교생리염수대조조경사체적명현축소(P＜0.01).②결혈급재관주후핵인자κBp65명현종포질전이도포핵.결혈6 h급24 h재관주N-을선반광안산조p65양성세포솔분별위(0.462±0.022)%,(0.452±0.015)%,여상응생리염수대조조[(0.563±0.028)%,(0.554±0.013)%]비교표체감소(P＜0.01).③N-을선반광안산예처리교생리염수예처리조망세포감소.결론:국조뇌결혈급재관주능사핵인자κBp65활화,삼여뇌결혈급재관주손상.N-을선반광안산가억제p65표체,감경신경손상,구유뇌보호작용.
BACKGROUND: Nuclear factor-kappa B (NF-κB) is an important transcription factor, which can promote the transcription of many target genes after activated.OBJECTIVE: To investigate the expressions of NF-κB in local cerebral ischemia-reperfusion and the influence of the pretreatment of the N-acetylcysteine.DESIGN: Randomized grouping experiment with animals as subjects.SETTING: Department of Neurology, the Second Clinical Medical College, Harbin Medical University.MATERIALS: The experiment was finished in the Animal Experimental Center and Laboratory of Pathology of Harbin Medical University. Ninetynine male healthy Wister rats were randomly divided into 3 groups: Sham-operated group(n=l 1), saline control group(n=44), N-acetylcysteine group(n=44).METHODS: Rat models of cerebral ischemia were made with the method of thread blocking improved by Longa et al in rats of the three groups. A nylon line with a smooth spherical captular end of 0.26 mm in diameter made by heating was inserted through the cut of crotch of the common carotid artery. The prepared line for common carotid artery was tied tightly and the arteriole clamp of internal carotid artery was unclamped. The nylon line entered the common carotid artery and the inserted length of the saline control group and the N-acetylcysteine group from the crotch of the internal and external carotid artery was calculated about (18.5±0.5)mm in order to obstruct the blood supply of the middle cerebral artery. The inserted depth in sham-operated group was less than 15 mm and the blood supply of the middle cerebral artery was kept normal. Intraperitoneal injection of N-acetylcysteine was given with 150 mg/kg at 30 minutes before ischemia in N-acetylcysteine group and injection of normal saline was given with equal volume at 30 minutes before ischemia in saline control group.Eleven rats each time in saline control group and N-acetylcysteine group were killed by cutting off heads at the time points of ischemia 6, 24 hours,and reperfusion 1 hour after ischemia 6, 24 hours. The express of NF-κB of brain tissue was observed with immunchistochemical method. Percentage of cerebral infarction of rats in each group was determined by dyeing of tetrachloro red tetrazoline. Apoptosis of brain tissue cells was detected with terminal deoxynucleotide transferase-mediated dUTP nick-end labeling (TUNEL).MAIN OUTCOME MESURES: Percentage of cerebral infart volume of rats in each group, the activity of combination of the NF-κB and apoptosis of cells.RESULTS: Ninety-nine animals attended the experiment, all of them entered the final analysis. ① Percentages of infarct volume at 1 hour of ischemia and 6, 24 hours of reperfusion in N-acetylcysteine group were (8.39±2.54)%, (24.54±6.02)% respectively, and that of corresponding saline control group were (15.50±4.18)%,(32.22±3.99)%. The focus of infartion with ischemia for 24 hours in each group was increased as compared with that for 6 hours and the infarct volume in group with N-acetylcysteine was obviously decreased as compared with that in saline control group (P ＜ 0.01). ② NF-κB p56 transfered from the kytoplasm to the nucelus after the ischemia and reperfusion. The rates of p56 masculine cells in N-acetylcysteine group of ischemia for 6 and 24 hours were (0.462±0.022)%, (0.452±0.015)% respectively, the express of which was decreased as compared with that in saline control group [(0.563±0.028 )%,(0.554±0.013)%] (P ＜ 0.01 ). ③ Cells of apoptosis pretreated with N-acetylcysteine were obviously decreased as compared with that pretreated with normal saline.CONCLUSION: Focal cerebral ischemia and reperfusion can activate NF-κB p65, which participate in the damage of cerebral ischemia and reperfusion. NF-κB can inhibit the express of p65, and relieve the nerve injury and so have the effct of protection for brain.