Park P O, Haglund U
Department of Surgery, University of Uppsala, Sweden.
Crit Care Med. 1992 Jan;20(1):135-9. doi: 10.1097/00003246-199201000-00026.
The objective of this study was to evaluate the histologic reconstitution of the small intestinal mucosa after a standardized ischemic injury and to determine if the early repair process takes place by cell renewal or migration of existing mucosal cells. Therefore, male Wistar rats, weighing 190 to 320 g, were subjected to total warm intestinal ischemia by means of a hydrostatic pressure clamp for 45 or 90 mins. These rats were compared to sham-operated controls. Intestinal biopsies were obtained just before reperfusion and at various times up to 48 hrs thereafter. Mucosal injury was evaluated microscopically by a blinded examiner.
Variable mucosal reconstitution occurred within 3 hrs, after 45 mins of ischemia, whereas mucosal repair required up to 18 hrs after 90 mins of ischemia. In a second series of experiments, 45 or 90 mins of ischemia and 5 hrs of reperfusion were followed by the iv administration of radioactively labeled thymidine. Intestinal biopsies were taken 1 hr later and prepared for autoradiography. No increase in mucosal mitoses was observed.
The mucosal reconstitution occurred rapidly after 45 mins and 90 mins of total warm intestinal ischemia and primarily through mucosal cell migration.
本研究的目的是评估标准化缺血性损伤后小肠黏膜的组织学重建情况，并确定早期修复过程是通过细胞更新还是现有黏膜细胞的迁移来进行的。因此，对体重190至320克的雄性Wistar大鼠，通过静水压力夹进行45或90分钟的完全热肠缺血处理。将这些大鼠与假手术对照组进行比较。在再灌注前及此后长达48小时的不同时间点获取肠道活检样本。由一位不知情的检查者通过显微镜评估黏膜损伤情况。
缺血45分钟后，3小时内出现了不同程度的黏膜重建，而缺血90分钟后，黏膜修复需要长达18小时。在第二系列实验中，缺血45或90分钟以及再灌注5小时后，静脉注射放射性标记的胸腺嘧啶核苷。1小时后取肠道活检样本并准备进行放射自显影。未观察到黏膜有丝分裂增加。
完全热肠缺血45分钟和90分钟后，黏膜重建迅速发生，且主要通过黏膜细胞迁移实现。
