七氟烷后处理对大鼠肠缺血再灌注时早期炎症反应的影响

Effect of sevoflurane postconditioning on early inflammatory responses during intestinal ischemia-reperfusion in rats

目的评价七氟烷后处理对大鼠肠缺血再灌注时早期炎症反应的影响。方法清洁级SD大鼠60只,8~10周龄,体重200~230 g,雌雄各半,采用随机数字表法分为3组(n=20):假手术组(Sham组)、肠缺血再灌注组(I/R组)和七氟烷后处理组(Sevo组)。I/R组和Sevo组采用无损伤动脉夹夹闭肠系膜上动脉根部60 min,然后松开动脉夹恢复灌注2 h的方法制备肠缺血再灌注损伤模型,Sham组只分离肠系膜上动脉,不夹闭。Sevo组于再灌注即刻持续吸入1.15%七氟烷30 min进行后处理。再灌注2 h时心脏穿刺取血样后处死大鼠,取小肠组织,光镜下观察病理学结果,并进行Chiu评分,测定血中性粒细胞L-选择素水平(流式细胞术)和小肠组织TNF-α表达(Western blot法)、MPO活性(分光光度法)。结果与Sham组比较,I/R组血中性粒细胞L-选择素水平升高,Sevo组血中性粒细胞L-选择素水平降低,I/R组和Sevo组小肠组织Chiu评分、TNF-α表达水平和MPO活性升高(P<0.05);与I/R组比较,Sevo组血中性粒细胞L-选择素水平、小肠组织Chiu评分、TNF-α表达水平和MPO活性降低(P<0.05),小肠组织病理学损伤减轻。结论七氟烷后处理减轻大鼠肠缺血再灌注损伤的机制可能与抑制早期炎症反应有关。

Objective To evaluate the effect of sevoflurane postconditioning on early inflammatory responses during intestinal ischemia-reperfusion(I/R)in rats.Methods Sixty clean-grade Sprague-Dawley rats,aged 8-10 weeks,weighing 200-230 g,were divided into 3 groups(n=20 each)using a random number table method:sham operation group(Sham group),intestinal I/R group(I/R group),and sevoflurane postconditioning group(Sevo group).Intestinal I/R was produced by occlusion of the superior mesenteric artery for 60 min followed by reperfusion for 2 h in anesthetized rats in I/R group and Sevo group.Laparotomy was performed,and the superior mesenteric artery was only isolated in Sham group.The rats inhaled 1.15%sevoflurane for 30 min for postconditioning in Sevo group.Blood samples were collected by cardiac puncture at 2 h of reperfusion,and then the rats were sacrificed.Samples of intestine were obtained for examination of the pathological changes of intestinal tissues(with a light microscope)which were scored according to Chiu and for determination of the neutrophil L-selectin levels in blood(by flow cytometry),tumor necrosis factor-alpha(TNF-a)expression(by Western blot),myeloperoxidase(MPO)activity(by spectrophotometry).Results Compared with group Sham,the neutropil L-selectin level in blood was significantly increased in group I/R and decreased in group Sevo,and Chiu′s score,TNF-a expression and MPO activity were significantly increased in I/R and Sevo groups(P<0.05).Compared with group I/R,the neutropil L-selectin level in blood,Chiu′s score,TNF-a expression,TNF-a expression and MPO activity were significantly decreased(P<0.05),and the pathological changes were significantly attenuated in group Sevo.Conclusion The mechanism by which sevoflurane postconditioning reduces intestinal I/R injury may be related to inhibiting early inflammatory responses in rats.