高位脊髓损伤大鼠α2-肾上腺素受体基因的变化  

Changes in α2-adrenergic receptors gene expression after high-level spinal cord injury in Wistar rats

作　　者：何星颖[1] 石学银[1] 袁红斌[1] 徐海涛[1] 王亚华[1] 

机构地区：[1]第二军医大学附属长征医院麻醉科,上海,200003

出　　处：《中华危重病急救医学》2008年第11期-,共3页Chinese Critical Care Medicine

基　　金：国家自然科学基金，上海市医药卫生科技发展基金

摘　　要：目的 研究大鼠高位脊髓损伤后脊髓α2-肾上腺素受体(α2-ARs)基因的变化特点,为临床围手术期麻醉管理提供实验依据.方法 采用改良Aliens打击法建立脊髓胸4节段重度损伤动物模型:分别于损伤后1、3 d及1、2、3、4周处死动物,取损伤段及邻近上下段脊髓组织.采用逆转录-聚合酶链反应(RT-PCR)测定脊髓不同节段α2-ARs mRNA表达.结果 与不损伤脊髓假手术组比较.损伤段以上节段在损伤后受体表达持续减少,2周达最低(P＜0.01),此后受体表达开始逐步增加,4周受体表达增加至正常水平;损伤段在损伤后受体表达持续减少,1周达最低(P＜0.01).此后受体表达开始逐步增加.但至4周时仍未恢复至正常水平(P＜0.05);损伤段以下节段在损伤后1 d受体表达减少(P＜0.05).但1周后增加至正常水平.4周时仍未见明显变化.结论 大鼠高位脊髓损伤4周后.损伤段脊髓a2-ARs表达下调.而邻近上下节段脊髓a2-ARs表达恢复至正常水平.α2-ARs数目表达变化可能是引起高位脊髓损伤后"脊髓休克"及自主反射异常的中枢机制之一.Objective To evaluate the change in α2-adrenergic receptors (α2-Ars) gene expression after high-level iniury of the spinal cord (SCI),aiming as developing a more effective perioperative anesthetic management for high-level SCI patients.Methods Adult male Wistar rats were anesihetized and severe spinal crush injury at T4 was produced using modified Aliens device.The expression of α2-Ars mRNA at different levels of spinal cord in normal control rats (C),injured segment (Ⅰ),above (A) and below (B) the site of injured segment,were measured by reverse transcription-polymerase chain reaction (RT-PCR) 1 day,3 days,1 week,2 weeks,3 weeks and 4 weeks,respectively after SCI.Results Compared with group C(sham group),in group A the expression of α2-Ars mRNA decreased 1 day after SCI (P＜ 0.05) and dropped to the nadir 2 weeks later (P＜0.01),but the expression was restored to the normal level 4 weeks later.In group Ⅰ the lowering of α2-Ars mRNA expression occurred immediately after SCI and down to the lowest value 1 week later (P＜0.01),and did not recover to normal level 4 weeks later (P＜0.05).In group B downregulation of α2-Ars mRNA expression was detected 1 day after SCI (P＜0.05),but it was upregulated 1 week later reaching the normal level,which was maintained for 4 weeks.Conclusion In a chronic SCI rat model,α2-Ars gene expression is downregulated in the injured segment,but returns to the normal level above and below the injured segment. The changes in α2-Ars may he a pivotal factor contributing to a series of abnormal responses after high-level SCI.

关 键 词：脊髓损伤 肾上腺素受体 基因表达 聚合酶链反应 

分 类 号：R686[医药卫生—骨科学]