摘要目的:评价术前睡眠剥夺加重老龄小鼠术后认知功能障碍的机制与海马CA1区theta振荡的关系。方法:SPF级雄性C57BL/6J小鼠24只，18月龄，体质量20～30 g，采用随机数字表法将小鼠分为3组( n＝8)：正常对照组(C组)、手术组(S组)和术前睡眠剥夺＋手术组(SD＋S组)。采用睡眠剥夺杆法建立睡眠剥夺模型，术前睡眠剥夺时间为24 h。C组无任何处理；S组异氟烷麻醉下行剖腹探查术；SD＋S组睡眠剥夺24 h后行异氟烷麻醉下剖腹探查术。采用Y迷宫和Morris水迷宫实验评估术后认知功能，采用在体脑电图电极记录Y迷宫测试期间小鼠海马CA1区theta振荡。之后处死小鼠取脑组织，采用高尔基染色观察海马CA1区树突棘密度。 结果:与C组相比，S组穿越原平台位置次数、目标象限停留时间、新臂探索时间和进入新臂次数减少，海马CA1区树突棘密度减少，Y迷宫测试期间theta振荡功率百分比降低( P<0.05)；与S组相比，SD＋S组穿越原平台位置次数、目标象限停留时间、新臂探索时间和新臂穿梭次数减少，海马CA1区树突棘密度减少，Y迷宫测试期间theta振荡功率百分比降低( P<0.05)。 结论:术前睡眠剥夺加重老龄小鼠术后认知功能障碍的机制可能与海马CA1区theta振荡减少有关。

abstractsObjective:To evaluate the relationship between the mechanism of preoperative sleep deprivation aggravating postoperative cognitive dysfunction and theta oscillations in the hippocampal CA1 region in aged mice.Methods:Twenty-four SPF male C57BL/6J mice, aged 18 months, weighing 20-30 g, were divided into 3 groups ( n=8 each) by a random number table method: normal control group (group C), operation group (group S) and preoperative sleep deprivation + operation group (group SD+ S). The sleep deprivation model was established using the sleep deprivation rod method, and the sleep deprivation time was 24 h before operation. The sleep deprivation rod was set to rotate continuously at 6 rpm/min, and the direction was randomly reversed to force the mice to exercise to achieve the purpose of sleep deprivation. Group C received no treatment. Group S underwent exploratory laparotomy under isoflurane anesthesia. After sleep deprivation for 24 h, SD+ S group underwent exploratory laparotomy under isoflurane anesthesia. Y-maze and Morris water maze tests were used to evaluate postoperative cognitive function. The theta oscillations in the hippocampal CA1 region were observed and recorded by EEG electrodes in vivo. The animals were then sacrificed and brain tissues were obtained for determination of the density of dendritic spines in the hippocampal CA1 region. Results:Compared with group C, the number of crossing the original platform was significantly decreased, and the time of staying at the original platform quadrant and time of exploring the novel arm were shortened, and the number of entries into the novel arm was reduced, the density of dendritic spines in the hippocampal CA1 region was reduced, and the percentage of theta oscillation power was decreased during the Y maze test in group S ( P<0.05). Compared with S group, the number of crossing the original platform was significantly decreased, and the time of staying at the original platform quadrant and time of exploring the novel arm were shortened, and the number of entries into the novel arm was reduced, the density of dendritic spines in the hippocampal CA1 region was reduced, and the percentage of theta oscillation power was decreased during the Y maze test in SD+ S group ( P<0.01). Conclusions:The mechanisms by which preoperative sleep deprivation exacerbates postoperative cognitive dysfunction may be related to reduction in theta oscillations in the hippocampal CA1 region of aged mice.