摘要目的 评价异构前列腺素15-F2t-isoprostane在大鼠肠缺血再灌注损伤中的作用.方法 健康雄性SD大鼠32只,体重230 ～ 255 g,采用随机数字表法,将其随机分为4组(n=8):假手术组(S组)、肠缺血再灌注组(I/R组)、血栓烷A2(TXA2)受体拮抗剂SQ-29548组(SQ组)和二甲基亚砜组(DMSO组).采用阻断肠系膜上动脉60 min,再灌注120 min的方法制备肠缺血再灌注损伤模型.SQ组及DMSO组分别于夹闭肠系膜上动脉前30 min腹部皮下注射SQ-29548或二甲基亚砜2μmol/kg.于再灌注120 min时取肠段,观察肠粘膜形态学,并行Chiu评分,取肠粘膜组织,检测髓过氧化物酶(MPO)、超氧化物歧化酶(SOD)活性和丙二醛(MDA)、乳酸(LD)含量；采集动脉血样,检测血清二胺氧化酶( DAO)活性及15-F2t-isoprostane、内皮素-1(ET-1)和血栓烷B2(TXB2)浓度.结果 与S组比较,其余各组Chiu评分、DAO活性、15-F2t-isoprostane及TXB2浓度均升高(P＜0.05),SQ组LD和MDA含量、MPO和SOD活性及ET-1浓度差异无统计学意义(P＞0.05)；与I/R组比较,SQ组Chiu评分、LD含量、DAO和MPO活性及ET-1浓度降低,SOD活性升高(P＜0.05).结论 15-F2t-isoprostane可通过激活TXA2受体,增加ET-1生成及促进中性粒细胞在肠粘膜聚集参与大鼠肠缺血再灌注损伤过程.

abstractsObjective To investigate the role of 15-F2t-isoprostane in intestinal injury induced by intestinal ischemia/reperfusion (I/R) in rats.Methods Thirty-two pathogen free adult male SD rats weighing 230-255 g were randomly divided into 4 groups ( n =8 each):group sham operation (group S) ; group intestinal I/R; group SQ-29548 (TXA2 receptor antagonist) (group SQ) and group DMSO (the solvent).Intestinal I/R was induced by 60 min occlusion of superior mesenteric artery (SMA) followed by 120 main reperfusion in groups I/R,SQ and DMSO SQ-29548 2 μmol/kg and DMSO were injected subcutaneusly at abdominal wall at 30 min before SMS in groups SQ and DMSO respectively.Arterial blood samples were taken at 120 min of reperfusion for determination of serum diamine oxidase (DAO) activity and 15-F2t-isoprostane,endothelin-1 (ET-1) and thromboxane B2 (TXB2) concentrations.Intestinal tissues were removed for microscopic examination and determination of myeloperoxidase (MPO) and SOD activities,MDA and lactate contents.Intestinal damage was assessed and scored according to Chiu (0 =normal,5 =disruption of tunica propria,bleeding and ulceration).Results Intestinal I/R significantly increased Chiu's score,MDA and lactate contents and MPO activity and decreased SOD activity in intestine in group I/R as compared with group S.SQ-29548 pretreatment significantly decreased Chiu's score,lactate content and MPO activity in intestine and increased intestinal SOD activity and decreased serum DAO activity and ET-1 concentration in group SQ as compared with group I/R.Conclusion 15-F2t-isoprostane is involved in the development of intestinal injury induced by intestinal I/R by activating TXA2 receptor,increasing ET-1 production and promoting neutrophil infiltration.