地塞米松对老龄大鼠术后认知功能的影响  

Effect of dexamethasone on postoperative cognitive function in rats

作　　者：李文瑶[1] 杨智勇[1] 李玉萍[1] 陶国才[1] 

机构地区：[1]第三军医大学附属西南医院手术麻醉科,重庆市400038

出　　处：《中华麻醉学杂志》2012年第10期1200-1203,共4页Chinese Journal of Anesthesiology

基　　金：国家自然科学基金（81171034）

摘　　要：目的评价地塞米松对老龄大鼠术后认知功能的影响。方法雄性sD大鼠180只，18～20月龄，体重400～600g，采用随机数字表法，将大鼠随机分为3组（n=60）：对照组（c组）、手术组（s组）和地塞米松组（D组）。采用大鼠剖腹探查手术模型。D组于麻醉开始时腹腔注射地塞米松10mg／kg。C组不进行手术，腹腔注射生理盐水2ml／kg。于术后3h、7d时测定海马OX42（小胶质细胞激活特异性标志物）的表达水平；于术后3h、1d、3d和7d时测定海马IL-1βmRNA和TNF—dmRNA的表达水平。采用Morris水迷宫实验和条件恐怖适应实验检测大鼠术后认知功能。结果与C组比较，s组和D组逃逸潜伏期延长，穿越原平台次数减少，术后僵直时间缩短，海马OX42表达、IL-1βmR．NA和TNF-a“mRNA表达上调（P〈0．05或0．01）；与s组比较，D组逃逸潜伏期缩短，穿越原平台次数增多，术后僵直时间延长，海马OX42、IL-IβmRNA和TNF．dmRNA表达下调（P〈0．05或0．01）。结论地塞米松可抑制海马小胶质细胞过度激活，减轻炎性反应，从而改善老龄大鼠术后认知功能。Objective To investigate the effect of dexamethasone on the postoperative cognitive function in rats. Methods One hundred and eighty Sprague-Dawley rats, aged 18-20 months, weighing 400-600 g, were randomly allocated into 3 groups （ n = 60 each） ：： control group （C group）, surgery group （S group） and dexamethasone group （D group） . In groups S and D, the rats were anesthetized with 5 % chloral hydrate 4-6 ml/kg and underwent abdominal surgery. The rats in group D received intraperitoneal injection of dexamethasone 10 mg/kg at the beginning of anesthesia, while the rats in group C underwent no surgery and received intraperitoneal injection of normal saline 1 ml/kg instead. Six rats in each group were chosen at 3 h and 7 days after surgery and sacrificed, and their brains were immediately removed for detection of the expression of OX42 （a specific marker for activation of microglia） in hippocampus. Another 6 rats in each group were chosen at 3 h, and 1, 3 and 7 days after surgery and sacrificed, and their brains were immediately removed for detection of the expression of IL-1β mRNA and TNF- a mRNA in hippocampus. Cognitive function was assessed by Morris water maze test and fear conditioning test. Re- suits Compared with group C, the escape latency was prolonged, the frequency of crossing the original platform was decreased, the postoperative freezing time was shortened, and the expression of OX42 after surgery and IL-1β mRNA and TNF-a mRNA at 3 h and 1 and 3 days after surgery was up-regulated in groups S and D （ P 〈 0.05 or 0.01 ）. Compared with group S, the escape latency was shortened, the frequency of crossing the original platform was increased, the postoperative freezing time was prolonged, and the expression of OX42 at 3 h after surgery and IL-1β mRNA and TNF-a mRNA at 3 h and 1 and 3 days after surgery was down-regulated in group D （ P 〈 0.05 or 0.01）. Conclusion Dexamethasone can inhibit the over-activation of microglia and reduce the inflammatory response, thus impr

关 键 词：地塞米松 认知障碍 手术后并发症 老年人 

分 类 号：R614[医药卫生—麻醉学]