幼年及成年大鼠肠缺血-再灌注肠组织学对照研究

目的在建立小肠缺血-再灌注（ intestinal ischemia-reperfusion injury, II/R）模型的基础上，比较II／R幼年及成年SD大鼠肠组织形态学变化。方法4周龄和10周龄SD大鼠，分为幼鼠组和成鼠组，每组5只大鼠用于作正常对照，余下15只用于建立II／R模型，分别于缺血前、缺血1h、再灌注1h和再灌注2h4个时间点取距回盲部5cm处肠管行组织学观察并进行Chiu’s氏6级评分，结果进行统计学分析。结果缺血1h可见绒毛倒伏但结构基本完整，绒毛下间隙增宽和充血；再灌注1h时出现绒毛坏死崩解脱落、小溃疡形成，多处固有层分离，毛细血管暴露，再灌注2h时肠组织损伤程度未见明显加重，但绒毛上皮细胞脱落，溃疡面增多，幼鼠组有明显的出血现象。肠组织病理改变的Chiu氏评分结果随缺血和再灌注时间的延长而评分增加，再灌注1h时幼鼠组的分值高于成鼠组（P〈0．05），其余各时间点两组评分值间的差异无显著性（P〉0．05）。结论肠组织病理损伤呈现随II／R的时间延长而加重，其中又以幼年大鼠肠组织损伤较严重且发展快。

Comparative morphological study about intestinal ischemia-reperfusion between young and adult rats

Objective To explore the difference of intestinal histological changes induces by ischemia-reperfusion （I/R） between young and adult rats. Methods 40 SD rats were divided into young and adult groups each 20 with 4 and 10 weeks old respectively. Based on the I/R model of superior mesenteric artery occluded, the intestinal specimens were harvested before and after ischemia 1 hour, reperfusion 1 hour and 2 hours, Chiu＇s scores were calculated according to their morphological changes were performed and the data analyzed statistically. Results There was pathological changes performance for chorionic villi lodging and hyperemia under villi space of intestine after ischemia. Villus necrosis and small ulcer formation, intrinsic layer separation can be found in intestine after reperfusion, there was the aggressive trend with the reperfusion time prolong especially in young group. But for the Chiu＇s score, its higher in young group at reperfusion lh than that in adult group only （ P 〈 0.05 ）, no significant difference the scores compared between two groups in another three observe time points （P 〉 0.05）. Conclusions Intestinal tissue damage induced by I/R is severer in young rat than adult and increased with reperfusion prolong.