Toll样受体4在机械通气致小鼠脑组织神经元凋亡中的作用  

Role of Toll-like receptor 4 in mechanical ventilation-induced neuronal apoptosis in brain tissues of mice

作　　者：陈婷[1] 邹玉凤[1] 陈畅[1] 张宗泽[1] 彭勉[1] 陈凯[1] 陈莹莹[1] 王焱林[1] 

机构地区：[1]武汉大学中南医院麻醉科,430071

出　　处：《中华麻醉学杂志》2016年第7期847-850,共4页Chinese Journal of Anesthesiology

基　　金：基金项目：国家自然科学基金（81571291）;湖北省卫生计生科研项目（WJ2015MB034）;湖北省自然科学基金杰出青年项目（2014CFA046）

摘　　要：目的探讨Toll样受体4（TLR4）在机械通气致小鼠脑组织神经元凋亡中的作用。方法健康雄性TLR4基因敲除（J003752）C57BL／10scNJNju小鼠和野生型C57BL／6小鼠各42只，10-12周龄，体重20～25g，采用随机数字表法，将2种小鼠各分为2组（n=21）：假手术组（S组）和机械通气组（MV组）。S组吸入异氟醚麻醉下自主呼吸6h，MV组行气管插管后异氟醚麻醉维持下机械通气6h。每组于机械通气后1、3d时取12只小鼠，进行恐惧条件化实验评价认知功能，计算僵直时间比率。于机械通气后1d处死3只小鼠，取脑组织，采用TUNEL法检测海马CAl区神经元凋亡情况，计算凋亡指数；于机械通气后1d处死6只小鼠，取海马，采用Western blot法检测Bax、Bcl-2、活化型caspase-9和活化型caspase-3的表达，计算Bax与Bcl-2表达的比值（Bax／Bcl-2比值）。结果与S组比较，野生型小鼠和TLR4基因敲除小鼠的MV组机械通气后1、3d时僵直时间比率降低，海马神经元凋亡指数和Bax／Bcl-2比值升高，海马活化型caspase-9和活化型caspase-3表达上调（P〈0．05或0．01）；与野生型小鼠的MV组比较，TLR4基因敲除小鼠的MV组机械通气后1、3d时僵直时间比率升高，海马神经元凋亡指数和Bax／Bcl-2比值下降，海马活化型caspase-9和活化型caspase-3表达下调（P〈0．05或0．01）。结论机械通气致小鼠脑组织神经元凋亡的机制部分与TLR4有关。Objective To investigate the role of Toll-like receptor 4 （TLR4） in mechanical ventilation-induced neuronal apoptosis in brain tissues of mice. Methods Forty-two heahhy male TLR4 gene knockout （J003752） C57BL/10ScNJNju mice and 42 wild type C56BL/6 mice, aged 10-12 weeks, weighing 20-25 g, were used in the study. The mice of either type were randomly divided into 2 groups （n= 21 each） using a random number table： sham operation group （group S） and mechanical ventilation group （group MV）. In group S, the mice were exposed to isoflurane for 6 h in an anesthesia chamber. In group MV, the mice were mechanically ventilated for 6 h after tracheal intubation when anesthesia was maintained with isoflurane. Twelve mice were selected from each group at 1 and 3 days after ventilation, fear condition- ing test was performed to assess the cognitive function, and the ratio of freezing time was recorded. Three mice in each group were sacrificed at 1 day after ventilation, the brains were removed for detection of neuronal apoptosis in the hippocampal CA1 region in the brain tissue by TUNEL, and the apoptosis index was calculated. Six mice in each group were sacrificed at 1 day after ventilation, the hippocampi were isolated for determination of the expression of Bax, Bcl-2, activated caspase-9 and activated caspase-3 by Western blot, and the Bax/Bcl-2 ratio was calculated. Results Compared with group S, the ratio of freezing time was significantly decreased at 1 and 3 days after ventilation, the apoptosis index and Bax/Bcl-2 ratio were significantly increased, and the expression of activated caspase-9 and activated caspase-3 was significantly up-regulated in group MV of TLR4 gene knockout and wild type mice （P〈0.05 or 0.01）. Compared with group MV of wild type mice, the ratio of freezing time was significantly increased at 1 and 3 days after ventilation, the apoptosis index and Bax/Bcl-2 ratio were significantly decreased, and the expression of activa- ted caspase-9 and activated caspase-3 was signifi

关 键 词：TOLL样受体4 呼吸 人工 细胞凋亡 神经元 脑 

分 类 号：R614[医药卫生—麻醉学]