异氟醚麻醉对老龄大鼠海马突触体蛋白质组的影响

Effects of isoflurane anesthesia on hippocampus synaptosomes proteome in aged rats

目的评价异氟醚麻醉对老龄大鼠海马突触体蛋白质组的影响。方法雌性SD大鼠27只，22月龄，体重480～550g，采用随机数字表法，将其随机分为2组：对照组（C组，n=6）和异氟醚麻醉组（I组，n=21）。C组吸入含80％氧气的空氧混合气体2h，I组吸入3％异氟醚麻醉诱导后，经口明视气管插管，吸入2％异氟醚＋80％氧气维持麻醉2h。麻醉结束后24h时，进行Y型迷宫实验测试大鼠认知功能，记录训练次数。以训练次数〉75次为判断认知功能低下的标准，将I组大鼠分为2组：认知功能低下组（IA组）和认知功能未低下组（IB组）。Y型迷宫实验结束后，处死大鼠，取双侧海马组织，提取突触体，进行双向凝胶电泳和质谱分析。结果I组有6只大鼠发生认知功能低下，有13只大鼠未发生认知功能低下。与C组和IB组比较，IA组训练次数增多（P〈0．05）；C组和IB组间比较训练次数差异无统计学意义（P〉0．05）。IB组和IA组差异表达的蛋白质有21个，其中11个蛋白质表达上调，10个蛋白质表达下调。C组和IA组差异表达的蛋白质有19个，其中12个蛋白质表达上调，7个蛋白质表达下调。经质谱分析鉴定出31个蛋白质。结论异氟醚麻醉导致老龄大鼠认知功能低下可能与突触部位能量代谢相关蛋白、突触部位的细胞骨架结构及调节蛋白的改变有关。

Objective To investigate the effects of isoflurane anesthesia on hippocampus synaptosomes proteome in aged rats. Methods Twenty-seven 22- month-old SD rats weighing 480-550 g were randomly divided into 2 groups： control group （group C, n = 6） and isoflurane group （group I, n = 21）. In group C inhaled mixed gas containing 80 % oxygen for 2 h. In group I the animals were endotracheal intubated after induction by 3 % isofiurane and inhaled 2% isoflurane and 80% oxygen for 2 h. Cognition function was evaluated by Y-maze at 24 h after anesthesia and the total training times were recorded. The total training times 〉 75 was defined as cognitive dysfuction. In group I the animals were divided into cognitive dysfuction group （group IA） and non-cognitive dysfuction group （group IB） according to the results of Y-maze test. The animals were sacrificed and their hippocampi were removed and syrtaptosomes were extracted for two-dimensional gel electrophoresis. The different protein spots were analyzed by mass chromatographic analysis. Results Six rats had cognitive dysfuction （group IA） and anoth- er thirteen rats had no cognitive dysfuction （group IB）. The total training times were significantly higher in group IA than in groups C and IB （ P 〈 0.05 ）. There was no significant difference in the total training times between groups C and I B （P 〉 0.05）. There were 21 （11/10） different protein spots between groups IB and IA, and 19 （12/7） different protein spots between groups C and IA. Thirty-one protein spots were identified by means of MAL- DI-TOF-MS. Conclusion The cognitive dysfuction after isoflurane anesthesia in aged rats may be related to the changes of energy metabolism protein, cytoskeletal structure and regulatory protein in synapse of hippocampus.