CAJ | 학술논문

目的评价短暂性全脑缺血再灌注时老年大鼠海马神经元AMP依赖性蛋白激酶(AMPK)信号转导通路的变化.方法健康老年雄性SD大鼠96只,18～ 22月龄,体重450 ～ 600 g,采用随机数字表法分为2组(n=36):假手术组(OS组)和短暂性全脑缺血再灌注组(OTIR组).健康青年雄性SD大鼠96只,2～3月龄,体重200～ 250 g,采用随机数字表法分为2组(n=48):假手术组(AS组)和短暂性全脑缺血再灌注组(ATIR组).采用Pusinelli四血管阻断法制备大鼠全脑缺血再灌注模型,缺血3 min后恢复灌注.于再灌注3、5和7d时每组随机取12只处死,取脑组织,分离海马CA1区,采用TUNEL法计数凋亡神经元,计算神经元凋亡率,采用Western blot法检测磷酸化AMPKα(p-AMPKα)的表达.结果与OS组比较,OTIR组各时点海马神经元凋亡率升高,p-AM PKα表达上调,AS组各时点海马神经元凋亡率降低,p-AMPKα表达下调(P＜0.05)；与AS组比较,ATIR组大鼠各时点海马神经元凋亡率升高,再灌注3和5d时海马神经元p-AMPKα上调(P＜0.05)；与OTIR组比较,ATIR组各时点海马神经元凋亡率降低,再灌注5和7d时海马神经元p-AMPKα表达下调(P＜0.05).结论短暂性全脑缺血再灌注时老年大鼠海马神经元AMPK信号转导通路激活,其激活程度较青年大鼠增强,脑缺血再灌注损伤程度加重.
목적 평개단잠성전뇌결혈재관주시노년대서해마신경원AMP의뢰성단백격매(AMPK)신호전도통로적변화.방법 건강노년웅성SD대서96지,18～ 22월령,체중450 ～ 600 g,채용수궤수자표법분위2조(n=36):가수술조(OS조)화단잠성전뇌결혈재관주조(OTIR조).건강청년웅성SD대서96지,2～3월령,체중200～ 250 g,채용수궤수자표법분위2조(n=48):가수술조(AS조)화단잠성전뇌결혈재관주조(ATIR조).채용Pusinelli사혈관조단법제비대서전뇌결혈재관주모형,결혈3 min후회복관주.우재관주3、5화7d시매조수궤취12지처사,취뇌조직,분리해마CA1구,채용TUNEL법계수조망신경원,계산신경원조망솔,채용Western blot법검측린산화AMPKα(p-AMPKα)적표체.결과 여OS조비교,OTIR조각시점해마신경원조망솔승고,p-AM PKα표체상조,AS조각시점해마신경원조망솔강저,p-AMPKα표체하조(P＜0.05)；여AS조비교,ATIR조대서각시점해마신경원조망솔승고,재관주3화5d시해마신경원p-AMPKα상조(P＜0.05)；여OTIR조비교,ATIR조각시점해마신경원조망솔강저,재관주5화7d시해마신경원p-AMPKα표체하조(P＜0.05).결론 단잠성전뇌결혈재관주시노년대서해마신경원AMPK신호전도통로격활,기격활정도교청년대서증강,뇌결혈재관주손상정도가중.
Objective To evaluate the changes in 5'-adenosine monophosphate-activated protein kinase (AMPK) signal transduction pathway in hippocampal neurons of aged rats during transient global cerebral ischemia/reperfusion (I/R).Methods Ninety-six aged male Sprague-Dawley rats aged 18-22 months,weighing 450-600 g,were randomly allocated to one of two groups (n=48 each):sham operation group (group OS) and transient global cerebral I/R group (group OTIR).Ninety-six yong male Sprague-Dawley rats aged 3 months,weighing 200-250 g,were randomly divided into 2 groups (n=48 each):sham operation group (group AS) and transient global cerebral I/R group (group ATIR).The global cerebral I/R was produced by 3 min four-vessel occlusion followed by reperfusion according to Pulsinelli.On 3,5 and 7 days of reperfusion,12 rats in each group were chosen and sacrificed.Their brains were removed and hippocampal CA1 region was dissected for detection of neuronal apoptosis (by TUNEL) and expression of phosphorylated AMPKα (p-AMPKα) (by Western blot).The apoptotic rate (AR) was calculated.Results Compared with OS group,the AR was significantly increased and the expression of p-AMPKα was up-regulated at each time point in OTIR group,and the AR was significantly decreased and the expression of p-AMPKα was down-regulated at each time point in AS group (P ＜ 0.05).Compared with AS groupthe AR was significantly increased at each time point and the expression of p-AMPKα was up-regulated on day 3 and 5 of reperfusion in ATIR group (P ＜ 0.05).The AR was significantly lower at each time point and the expression of p-AMPKα was down-regulated on day 5 and 7 of reperfusion in ATIR group than in OTIR group (P ＜ 0.05).Conclusion Transient global cerebral I/R can activate AMPK signal transduction pathway in hippocampus of aged rats.The activation of AMPK signal transduction pathway is stronger and the cerebral I/R injury is more severe in aged rats than in young rats.