七氟醚诱发大鼠认知功能障碍与大脑皮质α1B和α1D肾上腺素能受体的关系

Relationship between sevoflurane-induced cognitive impairment andα1B andα1D adrenoceptors in cerebral cortex of rats

目的评价七氟醚诱发大鼠认知功能障碍与大脑皮质α1B肾上腺素能受体(ADRA1B)和ADRA1D的关系。方法SPF级成年SD大鼠48只,雌雄各半,体重220~260 g,采用随机数字表法分为2组(n=24)∶对照组(C组)和七氟醚组(S组)。C组吸入空气,S组吸入3%七氟醚5 h。于麻醉后即刻,取8只大鼠处死后取大脑皮质组织,于麻醉后1和7 d,取8只大鼠,行巴恩斯迷宫实验,随后处死取大脑皮质组织,分别采用Western blot法和实时荧光定量PCR法检测大脑皮质ADRA1B、ADRA1D及其mRNA的表达水平。结果与C组比较,S组麻醉后1和7 d时错误进洞数增多,潜伏期和总路程延长,麻醉后即刻、1和7 d时大脑皮质ADRA1B、ADRA1D及其mRNA表达下调(P<0.05)。结论七氟醚诱发大鼠认知功能障碍的机制可能与大脑皮层ADRA1B和ADRA1D表达下调有关。

Objective To evaluate the relationship between sevoflurane-induced cognitive impairment andα1B adrenoceptors(ADRA1B)and ADRA1D in the cerebral cortex of rats.Methods Forty-eight SPF adult Sprague-Dawley rats(half male,half female),weighing 220-260 g,were divided into control group(C group,n=24)and sevoflurane group(S group,n=24)using a random number table method.Group C and group S inhaled air and 3%sevoflurane,respectively,for 5 h.Eight rats in each group were sacrificed immediately after anesthesia,and the cerebral cortex was removed.Eight rats in each group were selected on days 1 and 7 after anesthesia and underwent Barnes maze test.The rats were then sacrificed,and the cerebral cortex was removed.The expression of ADRA1B and ADRA1D protein and mRNA in cerebral cortex tissues was detected by Western blot and fluorescent quantitative real-time polymerase chain reaction,respectively.Results Compared with group C,the number of entering incorrect holes was significantly increased at 1 and 7 days after anesthesia,the latency and total distance to enter the target hole were prolonged,and the expression of ADRA1B and ADRA1D protein and mRNA in cerebral cortex was down-regulated immediately after anesthesia and at 1 and 7 days after anesthesia in group S(P<0.05).Conclusion The mechanism underlying sevoflurane-induced cognitive impairment may be related to the down-regulated expression of ADRA1B and ADRA1D in cerebral cortex of rats.