目的:观察吸入麻醉药异氟醚对转APP基因小鼠脑内海马神经元蛋白质损伤和蛋白聚集的影响,并探讨海藻糖对异氟醚诱导的神经毒性的干预作用。方法:60只12月龄转APP基因小鼠随机分为对照组、异氟醚组(Iso组)和海藻糖组(Tre组),每组20只。对照组小鼠不给予任何药物,将其置于持续通入2L·min^-1氧气的麻醉箱中2h;Iso组和Tre组小鼠于麻醉前30min分别经腹腔注射2mL生理盐水或海藻糖(400μg·kg^-1)稀释液,然后给予1.4%异氟醚吸入麻醉2h。麻醉后6h取小鼠海马组织制备脑组织匀浆,应用DCFH-DA荧光法检测小鼠海马组织中活性氧(ROS)水平;麻醉后24 h应用免疫组织化学法和Western blotting法检测小鼠海马组织中蛋白羰基化合物、硝基化酪氨酸和β-淀粉样蛋白(Aβ)1-42蛋白表达水平,应用透射电镜检测海马神经元中蛋白聚集物的形成,应用TUNEL染色法观察小鼠海马组织中神经元凋亡率。结果:与对照组比较,Iso组小鼠海马组织中ROS水平、氧化蛋白羰基化合物、硝基化酪氨酸、Aβ1-42蛋白表达水平和神经元凋亡率均明显增加(P〈0.05);与Iso组比较,Tre组小鼠海马组织中ROS水平、氧化蛋白羰基化合物、硝基化酪氨酸、Aβ1-42蛋白表达水平和神经元凋亡率均明显降低(P〈0.05)。结论:异氟醚能诱导转APP基因小鼠海马神经元蛋白质损伤和蛋白聚集,加剧氧化应激反应,增加脑内海马神经元凋亡,海藻糖能够拮抗异氟醚诱导的神经毒性。
Objective:To observe the influence of inhaled anesthetic isoflurane in the neuronal protein damage and aggregation in the APP transgenic mouse hippocampus,and to investigate the intervention effect of trehalose.Methods:Sixty APP transgenic mice aged 12 months were divided into control group,isoflurane group(Iso group)and trehalose group(Tre group)(n=20).The rats in control group were not given any drugs and were put into the anesthetic box with continuonsly entering 2L·min^-1 oxygen for 2h;the rats in Iso group and Tre group were respectively injected intraperitoneally with 2mL saline or trehalose(400μg·kg^-1)30min before anesthesia,and then inhalated 1.4%isoflurane for 2h.6hafter anesthesia,the hippocampus tissue of the mice was prepared,and DCFH-DA fluorescence was applied to detect the reactive oxygen species(ROS)level;24hafter anesthesia,immunohistochemical method and Western blotting method were used to detect the contents of carbonyl compounds and nitrotyrosine and the Aβ1-42 protein expression level in hippocampus;TEM was applied to observe the formation of protein aggregates;TUNEL staining was performed to observe the apoptotic rate of hippocampal neurons.Results:Compared with control group,the ROS level,the expression levels of oxidative protein carbonyl compounds and nitrotyrosine,the expression level of Aβ1-42 protein,and the apoptotic rate of hippocampal neurons in Iso group were significantly increased(P〈0.05);compared with Iso group,the ROS level,the expression levels of oxidative protein carbonyl compounds and nitrotyrosine,the Aβ1-42 protein expression level,and the apoptotic rate of hippocampal neurons in Tre group were significantly decreased(P〈0.05).Conclusion:Isoflurane can induce the protein damage and aggregation,the apoptotic rate of hippocampal neurons,aggravate oxidative stress reaction,increase the apoptotic rate of brain hippocampal neurons in the APP transgenic mice;trehalose can intervene the neurotoxicity induced by inhaled anesthetics.