Megison S M, Horton J W, Chao H, Walker P B
Department of Surgery, University of Texas Southwestern Medical Center, Dallas 75235-9031.
J Surg Res. 1990 Aug;49(2):168-73. doi: 10.1016/0022-4804(90)90257-3.
Many models of intestinal ischemia in the rat have been described yielding mortality rates of 8-80% following superior mesenteric artery (SMA) occlusion for periods of 1-85 min. These results have been difficult to reliably reproduce in our lab. Based on our theory that these inconsistent findings are secondary to individual variability in collateral circulation, we have developed a new model for intestinal ischemia with reproducible and consistent mortality. Male Sprague-Dawley rats weighting 300-400 g underwent celiotomy and evisceration. Occlusion of the superior mesenteric artery just distal to the right colic artery was achieved. Collateral arcades from the right colic artery and the jejunal arteries proximal to the site of occlusion were ligated and the bowel was returned to the abdomen for the remainder of the ischemic period. SMA occlusion alone and SMA occlusion with interruption of collateral flow were evaluated and compared for severity of ischemic injury reflected by mortality and for reproducibility of ischemia and mortality. Quantitative measurements of blood flow for each technique were made using radiolabeled microspheres, and a survival curve for SMA occlusion with collateral ligation was constructed. SMA occlusion alone in the rat is not a reliable model for mesenteric ischemia because the resulting ischemic injury is inconsistent and not reproducible. SMA occlusion with collateral ligation produced more severe and reproducible ischemia with greater mortality than did SMA occlusion alone. This technique produced mortality rates that were reproducible and were more consistently related to duration of ischemia.
许多大鼠肠缺血模型已被描述，在肠系膜上动脉（SMA）闭塞1 - 85分钟后，死亡率为8% - 80%。这些结果在我们实验室难以可靠地重复。基于我们的理论，即这些不一致的发现是由于侧支循环的个体差异所致，我们开发了一种新的肠缺血模型，其死亡率具有可重复性和一致性。体重300 - 400克的雄性Sprague - Dawley大鼠接受剖腹术和内脏摘除术。在右结肠动脉远端实现肠系膜上动脉闭塞。结扎来自右结肠动脉和闭塞部位近端空肠动脉的侧支血管弓，在缺血期剩余时间将肠管放回腹腔。评估并比较单独SMA闭塞以及SMA闭塞并中断侧支血流的情况，以死亡率反映的缺血损伤严重程度以及缺血和死亡率的可重复性。使用放射性标记微球对每种技术的血流量进行定量测量，并构建SMA闭塞并结扎侧支血管的生存曲线。单独SMA闭塞在大鼠中不是肠系膜缺血的可靠模型，因为由此产生的缺血损伤不一致且不可重复。与单独SMA闭塞相比，SMA闭塞并结扎侧支血管产生更严重且可重复的缺血，死亡率更高。该技术产生的死亡率具有可重复性，并且与缺血持续时间更一致相关。
