【作者】 肖倩；

【导师】 王白云； 唐小卿；

【作者基本信息】 南华大学 ， 临床医学（麻醉学）（专业学位）， 2017， 硕士

【摘要】 目的:首先观察麻醉和手术对老年大鼠海马自噬的影响,明确异氟烷吸入麻醉下实施剖腹探查术后的老年大鼠海马自噬受到损害,自噬水平下降,然后通过外源性给予H₂S,观察其对术后老年大鼠海马自噬受损的改善作用,以自噬作为切入点,为防治POCD提供新思路。方法:取75只健康清洁18-20月龄的Sprague Dawley（SD）雄性大鼠,按随机数字表法分为5组（15只/组）,分组如下:对照组、手术组（Postoperation）、低浓度H₂S组（Postoperation+NaHS30μmol/kg）、高浓度H₂S组（Postoperation+Na HS 100μmol/kg）和H₂S对照组（NaHS 100μmol/kg）,在手术组和高、低浓度H₂S组实施剖腹探查术之前,对高、低浓度H₂S组和H₂S对照组分别给予不同浓度的NaHS溶液腹腔注射14天,对照组和手术组每天腹腔注射等量PBS,连续14天。术后3天,取所有存活大鼠脑组织,透射电镜观察海马CA1区自噬小体数量,Western-Blot法分别检测大鼠海马CA1区LC3、Beclin1、P62蛋白的表达。结果:1.术后老年大鼠海马组织CA1区自噬障碍。1.1透射电镜观察术后老年大鼠海马组织CA1区自噬,结果表明手术组大鼠海马组织CA1区自噬小体和自噬溶酶体数目与对照组相比显著减少。说明术后老年大鼠海马组织自噬障碍。1.2与对照组相比,老年大鼠剖腹探查术后三天,老年大鼠海马组织CA1区自噬相关蛋白LC3的表达下调。1.3与对照组相比,老年大鼠剖腹探查术后三天,老年大鼠海马组织CA1区自噬相关蛋白Beclin1的表达下调。1.4与对照组相比,老年大鼠剖腹探查术后三天,老年大鼠海马组织CA1区自噬相关蛋白P62的表达上调。2.H₂S改善术后老年大鼠海马CA1区自噬障碍。2.1 NaHS（30,100μmol/kg/d）腹腔注射14天后行剖腹探查术,术后3天取海马组织采用透射电镜观察海马组织发现H₂S能增加术后老年大鼠海马CA1区自噬体结构的数量,且增加作用具有浓度依赖性。2.2剖腹探查术前14天预处理NaHS（30,100μmol/kg/d）,发现H₂S促进术后老年大鼠海马组织CA1区LC3的表达。2.3剖腹探查术前14天预处理NaHS（30,100μmol/kg/d）,发现H₂S上调术后老年大鼠海马CA1区Beclin1的表达。2.4剖腹探查术前14天预处理NaHS（30,100μmol/kg/d）,发现H₂S下调术后老年大鼠海马CA1区P62的表达。结论:1.术后老年大鼠海马组织自噬呈现障碍。2.H₂S促进术后老年大鼠海马组织自噬。更多还原

【Abstract】 Objective:To observe the effects of anesthesia and surgery on autophagy in hippocampus of aged rats and conclude isoflurane inhalation can damage the hippocampus of rats after laparotomy,Decrease autophagy level,And after through the administration of exogenous H₂S,the effect on impaired autophagy in hippocampus of aged rats after operation,with autophagy as a starting point,to provide new ideas for the prevention and treatment of POCD.Methods:Selecting 75 healthy clean 18-20 month old Sprague Dawley（SD）male rats were randomly divided into 5 groups（15/group）and control group（PBS）,operation group（Surgery+PBS）,low concentration of H₂S group（Surgery+NaHS 30 mol/kg）,high concentration H₂S group（Surgery+Na HS 100 mol/kg）.Before laparotomy,the low dose NaHS treatment and high dose NaHS treatment group and the simple NaHS treatment group,were treated with different concentrations of NaHS by intraperitoneal injection for 14 days.Control group and simple operation group intraperitoneal injection of PBS consecutively for 14days;At 3 days after operation,all the brain tissues of rats were survived,a number of autophagic bodies in CA1 area of hippocampus was observed by transmission electron microscope,Western-Blot method was used to detect the expression of LC3,Beclin1 and P62 in the hippocampal CA1 area of rats.Results:1.The disorder of CA1 in hippocampus of aged rats.1.1 The CA1area of hippocampus in aged rats was observed by transmission electron microscope.The results showed that the number of autophagic bodies and the number of autophagic lysosome in the CA1 area of hippocampus in the rats in the operation group was significantly lower than that in the control group.1.2 The expression of autophagy related protein LC3 in the hippocampal CA1 area of aged rats was decreased three days after laparotomy.1.3 The expression of autophagy related protein Beclin1 in the hippocampal CA1 area of aged rats was decreased three days after laparotomy.1.4 The expression of autophagy related protein CA1 in the hippocampus of P62 rats aged three days after laparotomy.2.H₂S can improve the dysfunction of hippocampus CA1 area in aged rats.2.1NaHS（30,100 mol/kg/d）was pretreated by for the first time on the first day of the laparotomy.The results showed that H₂S could improve the dysfunction of CA1 in the hippocampus of aged rats after operation.2.2NaHS（30,100 mol/kg/d）was pretreated for 14 days before laparotomy,and it was found that H₂S could promote the expression of CA1 in hippocampus of aged rats.2.3 NaHS（30,100 mol/kg/d）was pretreated for 14 days before laparotomy,and H₂S was found to up regulate the expression of CA1 in hippocampus of aged rats.2.4 NaHS（30,100mol/kg/d）was pretreated for 14 days before laparotomy,and H₂S was found to down regulate the expression of CA1 in the hippocampus of aged rats.Conclusion:1.The autophagy in hippocampus of postoperative aged rats is defected.2.H₂S ameliorates the impairement of autophagy in the hippocampus of postoperative aged rats.更多还原