脊髓GABAA受体在术前焦虑诱发大鼠术后痛觉过敏中的作用  

Role of spinal GABAA receptors in preoperative anxiety-induced postoperative hyperalgesia in rats

作　　者：张佐霞[1] 刘玥[1] 孙绕[1] 荣辉[1] 顾小萍[1] 马正良[1] 

机构地区：[1]南京大学医学院附属鼓楼医院麻醉科,210008

出　　处：《中华麻醉学杂志》2016年第8期978-981,共4页Chinese Journal of Anesthesiology

基　　金：国家自然科学基金（81471129）;江苏省医学重点学科（XK201140）

摘　　要：目的 探讨脊髓GABAA受体在术前焦虑诱发大鼠术后痛觉过敏中的作用.方法 清洁级健康雄性SD大鼠42只,6～8周龄,体重200～ 250 g,采用随机数字表法分为5组：对照组（C组,n=10）、手术组（O组,n=10）、术前焦虑组（PA组,n=10）、生理盐水组（NS组,n=6）和蝇覃醇组（M组,n=6）.采用单次延长应激法建立术前焦虑模型.C组仅进行七氟醚麻醉;O组于七氟醚麻醉下行右后足切口手术;PA组制备术前焦虑模型后行右后足切口手术;NS组于术前焦虑模型制备前30 min、术前30 min、术后1、2和3d时鞘内注射生理盐水10μl;M组于上述时点鞘内注射0.01 μg/μlGABAA受体激动剂蝇覃醇10μl.于术前焦虑模型制备前24 h（基础状态）、术后1、2、3、5和7d时测定机械缩足反应阈（MWT）.C组、O组和PA组分别于术后1和7d痛阈测定结束后,取脊髓组织,采用Western blot法测定GABAA受体的表达水平.结果 与C组及基础值比较,O组术后1～3dMWT降低,术后1d脊髓GABAA受体表达下调（P＜0.05）.与O组比较,PA组术后1～7 d MWT降低,术后1和7d脊髓GABAA受体表达下调（P＜0.05）.与PA组比较,M组术后1～7 d MWT升高（P＜0.05）.结论 术前焦虑诱发大鼠术后痛觉过敏的机制可能与抑制脊髓GABAA受体功能有关.Objective To investigate the role of spinal γ-aminobutyric acid A （GABAA） receptors in preoperative anxiety-induced postoperative hyperalgesia in rats.Methods Forty-two pathogen-free healthy male Sprague-Dawley rats,aged 6-8 weeks,weighing 200-250 g,were randomly divided into 5 groups using a random number table：control group （group C,n=10）,operation group （group O,n=10）,preoperative anxiety group （group PA,n=10）,normal saline group （group NS,n=6） and muscimol group （group M,n=6）.The rats were exposed to single prolonged stress to establish the model of preoperative anxiety.The rats were only anaesthetized with sevoflurane in group C.The rats were anesthetized with sevoflurane and underwent an incision operation on the right hindlimb in group O.In group PA,the rats underwent an incision operation on the right hindlimb after establishment of preoperative anxiety model.In group NS,normal saline 10 μl was injected intrathecally at 30 min before establishment of the model,at 30 min before operation,and on postoperative days 1,2 and 3.In group M,0.01 μg/μl GABAA receptor agonist muscimol 10 μl was injected intrathecally at the time points mentioned above.The mechanical paw withdrawal threshold （MWT） was measured at 24 h before establishment of the model （baseline） and on postoperative days 1,2,3,5 and 7.In C,O and PA groups,the lumbar segments （L3-5） of the spinal cord were removed after measurement of the pain threshold on postoperative days 1 and 7 for determination of GABAA receptor expression by Western blot.Results Compared with group C and the baseline values,the MWT was significantly decreased on postoperative days 1-3,and the expression of GABAA receptors was significantly down-regulated on postoperative day 1 in group O （P〈0.05）.Compared with group O,the MWT was significantly decreased on postoperative days 1-7,and the expression of GABAA receptors was significantly down-regulated on postoperative days 1 and 7 in group PA （P〈0.05）.Compared with group PA,t

关 键 词：焦虑 痛觉过敏 脊髓 

分 类 号：R614[医药卫生—麻醉学]