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目的:评价N-甲基-D-天冬氨酸受体(NMDA受体)在七氟烷麻醉致老龄小鼠海马神经元程序性坏死中的作用。方法:清洁级健康雄性C57BL/6小鼠90只，18月龄，体重27~30 g，采用随机数字表法分为3组(n n＝30)：对照组(C组)、七氟烷麻醉组(S组)和七氟烷麻醉+NMDA受体拮抗剂盐酸美金刚组(S+M组)。S组和S+M组小鼠连续3 d吸入3%七氟烷2 h，S+M组于每次吸入七氟烷前1 h腹腔注射盐酸美金刚20 mg/kg，C组只吸入纯氧。分别于麻醉前1 d、麻醉后3和7 d时每组随机取10只小鼠行Morris水迷宫实验。Morris水迷宫实验结束后立即处死小鼠取海马，于光镜下观察病理学结果，采用流式细胞术测定神经元程序性坏死率和胞浆游离钙离子浓度([Can 2+]n i)，Wes-tern blot法检测NMDA受体亚型GluN2A、GluN2B和受体相互作用蛋白激酶1(RIP1)的表达。n 结果:与C组比较，S组和S+M组麻醉后各时点逃避潜伏期延长，穿越原平台位置次数减少，海马[Can 2+]n i和神经元程序性坏死率升高，GluN2A、GluN2B和RIP1表达上调(n P<0.05)，病理学损伤加重；与S组比较，S+M组麻醉后各时点逃避潜伏期缩短，穿越原平台位置次数增加，海马[Can 2+]n i和神经元程序性坏死率降低，GluN2A、GluN2B和RIP1表达下调(n P<0.05)，病理学损伤减轻。n 结论:NMDA受体参与了七氟烷麻醉致老龄小鼠认知功能障碍的过程，其机制可能与促进海马神经元程序性坏死有关。“,”Objective:To evaluate the role of N-methyl-D-aspartate receptors (NMDA receptors) in sevoflurane anesthesia-caused necroptosis in hippocampal neurons of aged mice.Methods:Ninety clean-grade healthy male C57BL/6 mice, aged 18 months, weighing 27-30 g, were divided into 3 groups (n n=30 each) using a random number table method: control group (group C), sevoflurane anesthesia group (group S) and sevoflurane anesthesia plus NMDA receptor antagonist memantine hydrochloride group (group S+ M). Mice inhaled 3% sevoflurane for 2 h for 3 consecutive days in S group and S+ M group, and memantine hydrochloride 20 mg/kg was intraperitoneally injected at 1 h before each inhalation of sevoflurane in S+ M group.Mice only inhaled pure oxygen for 2 h in group C. Ten mice of each group were selected on 1 day before anesthesia and 3 and 7 days after anesthesia to perform Morris water maze test.The mice were sacrificed immediately after Morris water maze test, and hippocampus was removed for microscopic examination of pathological changes (with a light microscope) and for determination of the necroptosis rate of neurons and cytoplasmic free calcium concentration([Can 2+ ]n i)(by flow cytometry), and expression of NMDA receptor subtypes GluN2A, GluN2B and receptor-interacting protein kinase 1 (RIP1) (by Western blot).n Results:Compared with group C, the escape latency was significantly prolonged, and the frequency of crossing the original platform was decreased, and the [Can 2+ ]n i and neuronal necroptosis rate in the hippocampus were increased at each time point after anesthesia, and the expression of GluN2A, GluN2B and RIP1 was up-regulated(n P<0.05), and the pathologic changes were accentuated in S group and S+ M group.Compared with group S, the escape latency was significantly shortened, and the frequency of crossing the original platform was increased, and the [Can 2+ ]n i and neuronal necroptosis rate in the hippocampus were decreased at each time point after anesthesia, and the expression of GluN2A, GluN2B and RIP1 was down-regulated (n P<0.05), and the pathologic changes were attenuated in group S+ M.n Conclusions:NMDA receptors are involved in the process of cognitive dysfunction induced by sevoflurane anesthesia in aged mice, and the mechanism may be related to the promotion of necrptosis in hippocampal neurons.