中文摘要：

目的评价异氟醚／丙泊酚不同配伍麻醉对轻度认知功能障碍（MCI）大鼠术后认知功能的影响。方法健康雄性Wistar大鼠，16～18月龄，采用结扎双侧颈总动脉致其重度狭窄的方法，建立MCI模型。取MCI模型制备成功的大鼠150只，采用随机数字表法分为5组（n=30）：假手术组（S组）、异氟醚组（I组）、丙泊酚组（P组）和异氟醚／丙泊酚不同剂量配伍组（IP1,2组）。I组吸入1．9％异氟醚；P组静脉输注丙泊酚40mg·kg-1·h-1；IP1组吸入1．0％异氟醚，静脉输注丙泊酚20mg·kg-1·h-1；IP，组吸入1．4％异氟醚，静脉输注丙泊酚10mg·kg-1·h-1。各组麻醉时间均为3h，待大鼠翻正反射消失后行胫骨骨折切开复位内固定术。于术后7d行恐惧条件化测试与Y迷宫实验检测认知功能，取海马组织，尼氏染色确定海马CA1区存活神经元计数；免疫荧光法确定海马CA1区CCAAT／增强子结合蛋白同源蛋白（CHOP）及cflspase-12阳性神经元计数。结果与s组比较，IP2组、I组和P组N臂停留时间比率、僵直时间比率和存活神经元计数降低，CHOP阳性神经元计数和caspase-12阳性神经元计数升高（P〈0．05），IP1组上述指标差异无统计学意义（P〉0．05）；与IP1组比较，IP2组、I组和P组N臂停留时间比率、测试期僵直时间比率和存活神经元计数降低，CHOP阳性神经元计数和caspase-12阳性神经元计数升高（P〈0．05）；与IP2组比较，I组和P组N臂停留时间比率、测试期僵直时间比率和存活神经元计数降低，CHOP阳性神经元计数和caspase-12阳性神经元计数升高（P〈0．05）。结论1．0％异氟醚复合丙泊酚20mg·kg-1·h-1麻醉不加重MCI大鼠术后认知功能障碍。

英文摘要：

Objective To evaluate the effects of different ratios of medicine dosage for isoflurane and propofol on postoperative cognitive function of rats with mild cognitive impairment （MCI）. Methods Healthy male Wistar rats, aged 16- 18 months, were used in the study. MCI model was established by occlusion of bilateral common carotid arteries. One hundred and fifty rats with MCI were divided into 5 groups （n=30 each） using a random number table： sham operation group （ group S） , isoflurane group （group I） , propofol group （group P） and different ratios of medicine dosage for isoflurane and propofolgroups （IP1,2 groups）. The rats inhaled 1.9% isoflurane for 3 h in group I. Propofol 40 mg ·kg-1· h-1 was infused intravenously for 3 h in group P. The rats inhaled 1.0% isofluraue, and propofol 20 mg · kg-1 · h-1 was infused intravenously for 3 h in group IP1. The rats inhaled 1.4% isoflurane, and propofol 10 mg ·kg-1 · h-1 was infused intravenously for 3 h in group IP2. After disappearance of eyelash reflex, open reduction and internal fixation was performed after tibial fracture was induced. On 7 days after operation, contextual fear conditioning test and Y maze test were used to assess the cognitive function, and hippocampal tissues were obtained to count the viable neurons （using Nissl＇s staining） and CCAAT/ enhancer-binding protein homologous protein （CHOP） and caspase-12 positive neurons （by immunofluores- cence） in hippocampal CA1 region. Results Compared with group S, the rate of time spent in N arm, the rate of time spent freezing, and the number of viable neurons were significantly decreased, and the number of CHOP and caspase-12 positive neurons were significantly increased in IP2, I and P groups （P〈 0.05） , and no significant change was found in the parameters mentioned above in group IP1 （P〉0.05）. Compared with group IP1, the rate of time spent in N arm, the rate of time spent freezing, and the.number of viable neurons were significantly decreased, and the