异氟醚对老龄大鼠海马蛋白质组的影响

Effects of isoflurane on hippocampus proteome in aged rats

目的探讨异氟醚对老龄大鼠海马蛋白质组的影响。方法清洁级老龄雌性SD大鼠75只，22月龄，随机分为对照组（C组，n=35）和异氟醚组（I组，n=40）。C组吸入含40％氧气的空气2h，I组通过异氟醚挥发罐的调节使麻醉箱内异氟醚浓度为3％，待翻正反射消失后将异氟醚浓度降至1．2％，维持2h。I组苏醒后24h采用Y型迷宫实验检测认知功能，麻醉结束后24h和72h分别随机取5只大鼠，取海马行双向凝胶电泳和质谱分析。结果与C组比较，I组麻醉结束后24h和48h正确反应次数和主动回避次数降低，全天总反应时间延长（P〈0．05）；学习能力I组低于C组（P〈0．05）。2组麻醉结束后24h差异表达蛋白17种，其中6种蛋白质表达上调，11种蛋白质表达下调；2组麻醉结束后72h差异表达蛋白16个，其中10种蛋白质表达上调，6种蛋白质表达下调。结论异氟醚麻醉后早期老龄大鼠认知功能下降具有可逆性，这种现象可能与海马蛋白质组变化有关。

Objective To investigate the effects of isoflurane on learning and memory function and hippocampus proteome in aged rats. Methods Seventy-five 22 month old SD rats were randomly divided into control group （C, n = 35） and isoflurane group （Iso, n = 40） . The rats in Iso group inhaled 1.2% isoflurane in 40% 02 for 2 h while those in control group inhaled 40% O2-air. The animals underwent Y-maze test for the assessment of learning and memory function at 24, 48 and 72 h after termination of 2 h isoflurane inhalation. Five animals in each group were decapitated at 24 and 72 h after the termination of 2 h isoflurane inhalation respectively and their hippocampi were removed for two-dimensional gel electrophoresis. The different protein spots were analyzed by means of mass chromatography. Results The correct reaction and active avoidance rate were significantly lower in Iso group than in control group at 24 h and 48 h after termination of isoflurane or 02 inhalation. The total reactive time was significantly longer in group Iso than in control group at 48 h after termination of isoflurane or 02 inhalation. There were 17 （6/11） different protein spots between group Iso and group C at 24 h after isoflurane or O2 inhalation and 16 （10/6） different protein spots between group Iso and group C at 72 h after isoflurane or 02 inhalation. Twenty-two protein spots of all spots were identified by means of MALDI-TOF-MS. Conclusion The cognitive impairment after isoflurane anesthesia in aged rats is reversible and may be related to the alteration in proteome of hippocampus.