Milazzo V J, Ferrante R J, Sabido F, Silva M B, Hobson R W, Durán W N
Department of Physiology, UMDNJ-New Jersey Medical School, Newark 07103-2714, USA.
J Surg Res. 1996 Feb 15;61(1):139-42. doi: 10.1006/jsre.1996.0094.
Adhesion of leukocytes (L) to microvascular endothelium (E) is a required step in the L-E interaction leading to tissue injury in ischemia-reperfusion. To assess the optimum period for therapy aimed at ameliorating negative effects of this required step, we investigated the time course of L-E adhesion in the hamster cheek pouch using 2 hr of ischemia and 1 hr of reperfusion in our model of I-R injury (Am. J. Physiol-261: 1626, 1991). Leukocytes adhering (stationary for > or = 30 sec) to postcapillary venules (15-30 microns in diameter) were counted after labeling with acridine orange. Prior to the induction of ischemia, there were no significant differences in the number of adherent leukocytes in each area chosen for study (1.9 +/- 0.6 vs 2.0 +/- 0.3; mean number of leukocytes/100-microns vessel length +/- SD). After 10 and 20 min of reperfusion there was no significant difference in leukocyte adhesion in the ischemic area relative to the control (2.7 +/- 0.5 vs 2.8 +/- 0.8, and 5.3 +/- 2.8 vs 2.4 +/- 0.6, respectively). Leukocyte adherence increased significantly after 30 min of reperfusion and remained elevated at 1 hr of reperfusion in the postischemic area relative to the nonischemic control area (7.8 +/- 1.3 vs 3.6 +/- 0.6, and 8.3 +/- 0.8 vs 4.1 +/- 0.6, respectively; P < 0.01). Leukocyte adhesion in the postischemic area after 30 min reperfusion was not significantly different from the adhesion at the end of 1 hr reperfusion. These data suggest that (1) peak leukocyte adhesion occurs after 30 min of normal reperfusion and (2) postischemic therapeutic intervention may be most beneficial when instituted within this early time period.
白细胞（L）与微血管内皮细胞（E）的黏附是L-E相互作用导致缺血再灌注组织损伤的必要步骤。为评估旨在减轻这一必要步骤负面影响的最佳治疗时期，我们在仓鼠颊囊缺血再灌注损伤模型（《美国生理学杂志》-261: 1626, 1991）中，采用2小时缺血和1小时再灌注，研究了L-E黏附的时间进程。用吖啶橙标记后，对黏附于直径15 - 30微米的毛细血管后微静脉（静止≥30秒）的白细胞进行计数。在诱导缺血前，所选各研究区域内黏附白细胞的数量无显著差异（1.9±0.6对2.0±0.3；白细胞平均数/100微米血管长度±标准差）。再灌注10分钟和20分钟后，缺血区域的白细胞黏附与对照组相比无显著差异（分别为2.7±0.5对2.8±0.8，以及5.3±2.8对2.4±0.6）。与非缺血对照区域相比，再灌注30分钟后缺血区域的白细胞黏附显著增加，并在再灌注1小时时仍保持升高（分别为7.8±1.3对3.6±0.6，以及8.3±0.8对4.1±0.6；P<0.01）。再灌注30分钟后缺血区域的白细胞黏附与再灌注1小时末的黏附无显著差异。这些数据表明：（1）正常再灌注30分钟后白细胞黏附达到峰值；（2）缺血后治疗干预在这一早期时间段内实施可能最有益。
