海马PI3K/Akt信号通路在外源性食欲素A改善异氟醚致小鼠记忆功能减退中的作用  

Role of hippocampal PI3K/Akt signaling pathway in exogenous orexin A-induced improvement of isoflurane anesthesia-caused decline in memory function of mice

作　　者：赵广超 刘洪 董海龙 巩固[3] 熊利泽 Zhao Guangchao;Liu Hong;Dong Hailong;Gong Gu;Xiong Lize(Department of Anaesthesiology and Perioperative Medicine, Xijing Hospital, Xi′an 710032, China;Department of Anesthesiology, Sichuan Mianyang 404 Hospital, Mianyang 621000, China;Department of Anesthesiology, Chengdu Military General Hospital, Chengdu 610083, China)

机构地区：[1]空军军医大学西京医院麻醉与围术期医学科,西安市710032 [2]四川绵阳四0四医院麻醉科,621000 [3]成都军区总医院麻醉科,610083

出　　处：《中华麻醉学杂志》2018年第3期300-303,共4页Chinese Journal of Anesthesiology

基　　金：国家自然科学基金重点项目（81730032）

摘　　要：目的评价海马磷脂酰肌醇3-激酶/蛋白质丝氨酸苏氨酸激酶（PI3K/Akt）信号通路在外源性食欲素A改善异氟醚致小鼠记忆功能减退中的作用。方法清洁级健康成年雄性C57BL/6小鼠100只，体重20-25 g，侧脑室置管成功后，采用随机数字表法分为5组（n＝20）：对照组（C组）和异氟醚组（I组）给予生理盐水，食欲素A组（OA组）给予1.5 mmol/L食欲素A，食欲素A＋二甲基亚砜组（OA＋D组）给予1.5 mmol/L食欲素A（溶于二甲基亚砜），食欲素A＋PI3K抑制剂LY294002组（OA＋LY组）给予1.5 mmol/L食欲素A ＋10 mmol/L LY294002。除C组仅吸入纯氧2 h（氧流量2 L/min）外，其余各组小鼠均吸入1.4%异氟醚2 h，并于麻醉结束前15 min依上述浓度侧脑室注射相应药物2 μl。每组随机取12只小鼠于麻醉结束后2 h时行条件恐惧刺激实验，并于24 h后进行记忆提取。各组剩余8只小鼠于麻醉结束后2 h时处死取海马组织，采用Western blot法检测PI3K、Akt、磷酸化Akt（p-Akt）的表达。结果与C组比较，I组小鼠恐惧箱内僵直时间缩短，PI3K、Akt和p-Akt表达下调，p-Akt/Akt比值降低（P〈0.05）；与I组比较，OA组小鼠恐惧箱内僵直时间延长，PI3K和p-Akt表达上调，p-Akt/Akt比值升高（P〈0.05）；OA组和OA＋D组各指标比较差异无统计学意义（P〉0.05）；与OA＋D组比较，OA＋LY组小鼠恐惧箱内僵直时间缩短，PI3K、Akt、p-Akt表达下调，p-Akt/Akt比值降低（P〈0.05）。结论海马PI3K/Akt信号通路参与了外源性食欲素A改善异氟醚致小鼠记忆功能减退的过程。Objective To evaluate the role of hippocampal phosphatidylinositol 3-kinase/serine-threonine kinase （PI3K/Akt） signaling pathway in exogenous orexin A-induced improvement of isoflurane anesthesia-caused decline in memory function of mice.Methods A total of 100 pathogen-free healthy adult male C57BL/6 mice, aged 8-12 weeks, weighing 20-25 g, in which the lateral ventricle was catheterized, were divided into 5 groups （n=20 each） using a random number table： control group （group C）, isoflurane group （group I）, orexin A group （group OA）, orexin A plus dimethyl sulfoxide group （group OA＋ D） and orexin A plus PI3K inhibitor LY294002 group （group OA＋ LY）. Normal saline was administrated in group C and group I. Orexin A 1.5 mmol/L was given in group OA.Orexin A 1.5 mmol/L （dissolved in dimethyl sulfoxide） was given in group OA＋ D.Orexin A 1.5 mmol/L and LY294002 10 mmol/L were given in group OA＋ LY.Group C only inhaled pure oxygen for 2 h （oxygen flow rate 2 L/min）, all the rest groups inhaled 1.4% isoflurane for 2 h, and the corresponding drug 2 μl was injected into the lateral cerebral ventricle according to the concentration mentioned above at 15 min before the end of anesthesia.Twelve mice were randomly selected from each group and trained for contextual fear conditioning test, and then fear memory retrieval was conducted at 24 h after training.The rest 8 mice in each group were sacrificed at 2 h after the end of anesthesia and their brains were removed for determination of the expression of PI3K, Akt and phosphor-Akt （p-Akt） protein by Western blot.Results Compared with group C, the freezing time was significantly shortened, the expression of PI3K, Akt and p-Akt was down-regulated, and p-Akt/Akt ratio was decreased in group I （P〈0.05）. Compared with group I, the freezing time was significantly prolonged, the expression of PI3K, Akt and p-Akt was up-regulated, and p-Akt/Akt ratio was increased in group OA （P〈0.05）. There was no significant difference in e

关 键 词：1-磷脂酰肌醇3-激酶 蛋白质丝氨酸苏氨酸激酶 异氟醚 记忆障碍 食欲素A 

分 类 号：R614[医药卫生—麻醉学]