老龄大鼠脑缺血再灌注一氧化氮和肿瘤坏死因子的变化及其意义

目的：根据一氧化氮（NO）和肿瘤坏死因子（TNF）的变化研究老龄大鼠脑缺血再灌注损伤的机制，为揭示脑梗塞的病理生理提供依据。方法：青年（5月龄）和老龄（20月龄以上）大鼠均分为模型组和正常对照组，观察大鼠全脑缺血30min再灌注60min后血NO和脑组织中NO，一氧化氮合成酶（NOS），TNF的水平。结果：老龄模型组血清中NO水平低于老龄对照组＊P＜0．05），脑组织中NO水平青年对照组高于青年模型组（P＜0．05），低于老龄对照组（P＜0．05），老龄模型组高于青年模型组（P＜0．01），青年模型组脑组织中NOS水平高于青年对照组和 老龄模型组（P＜0．05），青年模型组脑中TNF水平高于青年对照组（P＜0．05），老龄模型组高于青年模型组＊P＜0．05）和老龄对照组（P＜0．01），结论：青年大鼠和老龄大鼠脑缺血再灌注脑组织损伤与NO含量降低和TNF增高有关，由于老龄大鼠的增龄变化，使脑缺血再灌注后这些病理改变较青年大鼠更为严重。

Changes of nitric oxide and tumorous necrotic factor levels in aged rats with brain ischemia reperfusion

? Objective To explore the mechanism of brain ischemia reperfusion injury from the changes of nitric oxide(NO) and tumorous necrotic factor(TNF) in the aged rats, provide the evidence to clarify the pathophysiology of cerebral infarction.Methods Young(5 months)and aged(20 months or more)rats were divided into model groups and normal control groups respectively.It was measured that the NO levels, nitric oxide synthetase(NOS) activity, TNF levels.Results The serum NO level in aged model group was higher than that in the aged control group( P <0 05).The brain tissue NO level in young control group was higher than that in the young model group( P <0 01) and lower than that in the aged control group( P <0 05); and was higher in aged model group than that in the young model group( P <0 01).Comparing the young control and the aged model group, the brain tissue NOS activity in the young model was high( P <0 05).Brain TNF level in young model group was higher than that in the young control( P <0 05),the TNF level in aged model group was higher than that in the young model( P <0 05)and the aged control( P <0 01).Conclusions The brain ischemia reperfusion injury in young and the aged rats were correlated with the decrease of NO level and the increase of TNF.The pathological changes in aged rats with brain ischemia reperfusion was more serious with aging than that in the young rats.