CAJ | 학술논문

目的评价线粒体ATP敏感性钾通道在异氟醚预处理减轻大鼠脑缺血再灌注损伤中的作用及其与c-Jun氨基末端激酶(JNK)信号通路的关系.方法清洁级健康成年雄性SD大鼠32只,体重280 ～ 320 g,采用随机数字表法分为4组(n=8):假手术组(S组)、脑缺血再灌注组(I/R组)、异氟醚预处理组(Ⅰ-pre组)和5-羟葵酸组(5-HD组).I/R组采用改良Pulsinelli四血管阻断法制备大鼠全脑缺血再灌注模型;Ⅰ-pre组在缺血前每天吸入1.5％异氟醚1h,连续5 d;5-HD组处理同Ⅰ-pre组,在缺血处理前30 min腹腔注射5-羟癸酸15 mg/kg.于再灌注24 h时行神经行为学评分,于再灌注72h时处死大鼠取海马组织,采用TUNEL法检测凋亡神经元,计算神经元凋亡率,免疫组化法检测caspase-3表达,Westem blot法检测磷酸化JNK (p-JNK)蛋白表达.结果与S组比较,I/R组、Ⅰ-pre组和5-HD组格子爬行数减少,悬挂时间缩短,海马神经元凋亡率升高,caspase-3表达上调,I/R组和5-HD组p-JNK蛋白表达上调(P＜0.05),Ⅰ-pre组p-JNK蛋白表达差异无统计学意义(P＞0.05);与I/R组比较,Ⅰ-pre组格子爬行数增多,悬挂时间延长,海马神经元凋亡率降低,caspase-3和p-JNK蛋白表达下调(P＜0.05),5-HD组上述指标差异无统计学意义(P＞0,05);与Ⅰ-pre组比较,5-HD组格子爬行数减少,悬挂时间缩短,海马神经元凋亡率升高,caspase-3和p-JNK蛋白表达上调(P＜0.05).结论线粒体ATP敏感性钾通道可通过阻断JNK信号通路参与异氟醚预处理减轻大鼠脑缺血再灌注损伤的过程.
목적 평개선립체ATP민감성갑통도재이불미예처리감경대서뇌결혈재관주손상중적작용급기여c-Jun안기말단격매(JNK)신호통로적관계.방법 청길급건강성년웅성SD대서32지,체중280 ～ 320 g,채용수궤수자표법분위4조(n=8):가수술조(S조)、뇌결혈재관주조(I/R조)、이불미예처리조(Ⅰ-pre조)화5-간규산조(5-HD조).I/R조채용개량Pulsinelli사혈관조단법제비대서전뇌결혈재관주모형;Ⅰ-pre조재결혈전매천흡입1.5％이불미1h,련속5 d;5-HD조처리동Ⅰ-pre조,재결혈처리전30 min복강주사5-간계산15 mg/kg.우재관주24 h시행신경행위학평분,우재관주72h시처사대서취해마조직,채용TUNEL법검측조망신경원,계산신경원조망솔,면역조화법검측caspase-3표체,Westem blot법검측린산화JNK (p-JNK)단백표체.결과 여S조비교,I/R조、Ⅰ-pre조화5-HD조격자파행수감소,현괘시간축단,해마신경원조망솔승고,caspase-3표체상조,I/R조화5-HD조p-JNK단백표체상조(P＜0.05),Ⅰ-pre조p-JNK단백표체차이무통계학의의(P＞0.05);여I/R조비교,Ⅰ-pre조격자파행수증다,현괘시간연장,해마신경원조망솔강저,caspase-3화p-JNK단백표체하조(P＜0.05),5-HD조상술지표차이무통계학의의(P＞0,05);여Ⅰ-pre조비교,5-HD조격자파행수감소,현괘시간축단,해마신경원조망솔승고,caspase-3화p-JNK단백표체상조(P＜0.05).결론 선립체ATP민감성갑통도가통과조단JNK신호통로삼여이불미예처리감경대서뇌결혈재관주손상적과정.
Objective To evaluate the role of mitochondrial ATP-sensitive potassium (mitoKATP) channel in mitigation of cerebral ischemia-reperfusion (I/R) injury by isoflurane preconditioning in rats and the relationship with c-Jun N-terminal kinase (JNK) signaling pathway.Methods Thirty-two male Sprague-Dawley rats,weighing 280-320 g,were randomly divided into 4 groups (n =8 each) using a random number table:sham operation group (group S),group I/R,isoflurane preconditioning group (group Ⅰ-pre),and 5-hydroxydecanoate (5-HD,a selective mitoKATP channel antagonist) group.Cerebral I/R was produced by modified 4-vessel technique described by Pulsinelli in anesthetized rats.In group Ⅰ-pre,the rats were exposed to 1.5％ isoflurane for 1 h everyday for 5 consecutive days before ischemia.In group 5-HD,5-HD 15 mg/kg was injected intraperitoneally at 30 min before ischemia and the other procedures were similar to those previously described in group Ⅰ-pre.Neurological behavior was evaluated at 24 h of reperfusion.The rats in each group were sacrificed at 72 h of reperfusion,and the brains were removed for determination of neuronal apoptosis (by TUNEL) and expression of caspase-3 and phosphor-JNK (p-JNK) protein (using Western blot) in hippocampal tissues.Apoptotic rate was calculated.Results Compared with group S,the number of grid cross was significantly decreased,hanging time was shortened,apoptotic rate was increased,and caspase-3 expression was up-regulated in I/R,Ⅰ-pre and 5-HD groups,the expression of p-JNK protein was up-regulated in IR and 5-HD groups,and no significant change was found in the expression of p-JNK protein in group Ⅰ-pre.Compare with group I/R,the number of grid cross was significantly increased,hanging time was prolonged,apoptotic rate was decreased,and the expression of caspase-3 and p-JNK protein was downregulated in group Ⅰ-pre,and no significant change was found in the parameters mentioned above in group 5-HD.Compared with group Ⅰ-pre,the number of grid cross was significantly decreased,hanging time was shortened,apoptotic rate was increased,and the expression of caspase-3 and p-JNK protein was up-regulated in group 5-HD.Conclusion The mitoKATP channel is involved in mitigation of cerebral I/R injury by isoflurane preconditioning through blocking the JNK signaling pathway in rats.