重组人促红细胞生成素对大鼠肠系膜缺血再灌注损伤影响的实验研究

目的观察重组人促红细胞生成素(rHuEPO)对小肠缺血再灌注(IR)的影响,探讨rHuEPO对IR的保护作用。方法 90只雄性SD大鼠随机分为3组:假手术组(n=30),缺血再灌注(IR)损伤组(n=30)和重组人促红细胞生成素(rHuEPO)干预+IR组(n=30)。采用肠系膜上动脉无创性暂时阻断30min,之后恢复肠系膜血流再灌注60min的方法构建大鼠肠系膜缺血再灌注损伤模型,在肠系膜上动脉阻断之前30min给予5000u/kgrHuEPO腹腔注射。心室穿刺取血制备血清样本,通过硫代巴比妥酸反应方法来测定血清丙二醛(MDA)含量;取大鼠远端回肠制备肠组织匀浆样本,比色法测定样本髓过氧化物酶(MPO)活性。采用Park/Chiu对肠组织损伤程度进行组织病理学评分。结果假手术组大鼠没有观察到明显的肠黏膜损伤;IR损伤组大鼠肠黏膜表现出较为显著的组织病理学损伤,绒毛剥脱,上皮层和固有层大量分离,从绒毛尖端开始向浆膜层进展,毛细血管扩张充血;促红素处理组大鼠肠黏膜损伤显著减轻,仅有轻度的上皮下间隙形成,较轻微的上皮层从固有层分离及毛细血管充血。IR损伤组大鼠血清MDA、MPO水平及Chiu评分显著高于假手术组,相比较差异有显著性(r=6.912,24.376,19.553,P<0.05);经rHuEPO干预后,rHuEPO+IR组大鼠血清MDA、MPO水平及Chiu评分显著降低,与IR损伤组比较差异有显著性(r=3.853,7.835,4.851,P<0.05)。Chiu评分与血清MDA、MPO含量之间呈显著正相关性(r=0.915,0.904,P=0.010,0.013<0.05)。结论 rHuEPO可能通过其抗氧化、抗炎效应从而减轻大鼠肠缺血再灌注损伤。

Experimental study of recombinant human erythropoietin to protect against injury of intestinal ischemia-reperfusion in rats

【Objective】 To investigate whether ischemic preconditioning plays a role in intestinal ischemia-reperfusion injury and the protective effect of recombinant human erythropoietin(rHuEPO) on ischemia-reperfusion(IR).【Methods】 Ninety male SD rats were randomly divided into three groups,the sham operation group(n =30),renal IR group(n =30),and rHuEPO treatment group combined IR group(n =30).Establishment of the rat mesenteric ischemia-reperfusion injury model was to perform a midline laparotomy under general anesthesia with superior mesenteric artery(SMA) occlusion 30 min subsequently reperfusion 60 min using a traumatic vascular micro clip.Before SMA occlusion 30 min,the rats were given 5000 U/kg rHuEPO intraperitoneally.Blood samples were gathered through ventricular punctuation,serum MDA contents were determined in a method of the thiobarbituric acid reaction.Intestinal tissue samples were taken from the distal ileum segments for the preparation of intestinal tissue homogenate,intestinal tissue MPO activities were measured by means of chromatometry.Intestinal tissue specimen were evaluated histopathologically using Chiu scoring system.【Results】 Histopathological features of normal ileal tissue and no evident mucosal injury were observed in the sham group.In the ischemia-reperfusion group,the villi were denuded to the level of the lamina propria and dilated capillaries,disintegration of lamina propria,hemorrhage,manifesting severe mucosal injury.In the EPO group,slight mucosal injury were observed,such as small sub epithelial detachments,occasionally occurred subepithelial detachments exerted a slight amount of upward push on the mucosa epithelium,few denuded villus tips were observed,most villi are preserved intact,no disintegration of lamina propria,no hemorrhage or ulceration formation,manifesting slight mucosal injury.The serum MDA,MPO levels and Chiu score of the IR injury group were significantly higher than the sham group,compared the difference was significant(t =6.912,24.376,19.553,P <0.05);Intervention by rHuEPO,the serum MDA,MPO levels and Chiu score of the rHuEPO+IR injury group were significantly lower than the IR injury group,compared the difference was significant(t =3.853,7.835,4.851,P <0.05).Chiu score was significantly positive correlation with the serum MDA,MPO levels(r =0.915,0.904,P =0.010,0.013<0.05).【Conclusions】 rHuEPO protects the intestine of rats against mesenteric ischemia-reperfusion injury mediated by anti-oxidative,anti-inflammatory.