Suval W D, Durán W N, Borić M P, Hobson R W, Berendsen P B, Ritter A B
Am J Surg. 1987 Aug;154(2):211-8. doi: 10.1016/0002-9610(87)90181-4.
We determined the leakage of macromolecules using FITC-dextran-150 as a tracer and measured the extent of no-reflow phenomenon by video field analysis. The cremaster muscle of anesthetized rats was fashioned as a single layer, splayed on a lucite chamber and suffused with bicarbonate solution at 35 degrees C. After a 1 hour period of baseline data collection, ischemia was produced by cross-clamping the cremasteric vascular pedicle for periods of 30 minutes and 2 hours in separate experiments. Macromolecular leakage was visualized after reinstitution of perfusion. Leakage occurred at postcapillary venules 15 to 50 micron in diameter and quickly spread to the interstitium. The magnitude of leakage decreased as a function of time with continuous buffer suffusion, but remained higher than in the control period. No reflow occurred in approximately 30 percent of the muscle microvasculature upon reperfusion. The no-reflow values at 30 minute and 2 hour periods of ischemia were significantly different from the control values but were not from each other. Electron micrographs demonstrated endothelial cell swelling and migration of leukocytes and normal myocytes after 1 hour of reperfusion following 2 hours of ischemia. Our results demonstrate that permeability changes, occurrence of no reflow, and leukocyte migration precede the onset of damage to skeletal muscle in ischemia and reperfusion injury.
我们使用异硫氰酸荧光素标记的葡聚糖-150作为示踪剂来测定大分子的渗漏情况，并通过视频场分析来测量无复流现象的程度。将麻醉大鼠的提睾肌制成单层，铺展在有机玻璃腔室上，并在35摄氏度下用碳酸氢盐溶液灌注。在收集1小时的基线数据后，在单独的实验中通过交叉夹闭提睾肌血管蒂30分钟和2小时来造成缺血。恢复灌注后观察大分子渗漏情况。渗漏发生在直径为15至50微米的毛细血管后微静脉处，并迅速扩散到间质。随着持续缓冲液灌注，渗漏程度随时间下降，但仍高于对照期。再灌注时约30%的肌肉微血管出现无复流现象。缺血30分钟和2小时时的无复流值与对照值有显著差异，但两者之间无显著差异。电子显微镜照片显示，缺血2小时后再灌注1小时，内皮细胞肿胀，白细胞和正常心肌细胞迁移。我们的结果表明，在缺血再灌注损伤中，通透性改变、无复流的发生以及白细胞迁移先于骨骼肌损伤的发生。
