ENDOTHELIAL INJURY IN TRAUMA AND ISCHEMIA--REPERFUSION

这项建议的主要目的是阐明 血管再灌注后发生的内皮功能障碍 缺血的冠状动脉或内脏血管或在软组织诱导后 组织创伤。内皮功能障碍的主要表现是 基础释放和激动剂刺激释放显著减少 一氧化氮(NO)。负责减少的主要机制 NO的释放增加了超氧阴离子自由基的形成， 灭活NO，(B)多形核(PMN)白细胞与 内皮细胞(EC)和(C)结构性一氧化氮的抑制 合成酶。先前的提议是针对研究时间的。 血管内皮细胞功能障碍的病程及其与NO的相互作用 氧产生的自由基。本提案的主要主旨是 探讨PMN-EC相互作用的黏附分子 并将这些相互作用与组织损伤联系起来，因为PMN发挥着 在再灌流损伤中的重要作用甚至超越了对 内皮细胞。为了实现这些目标，我们将研究 抗L-选择素和CD_(18)的单抗 中性粒细胞细胞膜以及针对ICAM-1，PECAM-1， P-选择素和L-选择素对内皮细胞的影响。其他研究将包括 使用抗选择素寡糖(即唾液酸基Lewis[X])进行 类比)。利用流式细胞术和免疫组织化学，我们将 确定这些粘连的激活和失活的时间进程 分子，它们之间的相互作用以及它们对 再灌注和创伤所致的内皮功能障碍。用人 活体显微镜，我们将直接观察白细胞-EC 微血管系统(即肠系膜)水平上的相互作用 小静脉)。进一步的工作将指向研究细胞事件在 培养的内皮细胞，并研究其衰减机制。 再灌流诱导内皮细胞粘附性增加和NO减少 一代。这些发现应该会为我们提供重要的基本见解 心肌和内脏的病理生理学和治疗学 缺血/再灌流和创伤性休克。所有这些都是严肃的生活 威胁性疾病及其病理生理学知识提供了 对于治疗这些疾病的临床医生来说，这是重要的信息。

The major objective of this proposal is to elucidate the mechanism of the endothelial dysfunction occurring after reperfusion of a previously ischemic coronary or splanchnic vasculature or after induction of soft tissue trauma. The major manifestation of the endothelial dysfunction is a marked reduction in the basal release and agonist-stimulated release of nitric oxide (NO). The primary mechanisms responsible for the reduced release of NO are (a) increased superoxide radical formation which inactivates NO, (b)polymorphonuclear (PMN) leukocyte adherence to endothelial cells (EC), and (c) inhibition of constitutive nitric oxide synthase. The previous proposal was directed toward studying the time course of the endothelial dysfunction and the interactions between NO and oxygen derived free radicals. The major thrust of the present proposal is to investigate the adhesion molecules responsible for PMN-EC interaction and to relate these interactions to tissue injury, since PMNs play a significant role in reperfusion injury even beyond adherence to the endothelium. In order to achieve these goals, we will study the effect of monoclonal antibodies (MAb) directed against L-selectin and CD18 on the neutrophil cell membrane as well as MAbs directed against ICAM-1, PECAM-1, P-selectin and L-selectin on endothelial cells. Additional studies will be conducted using anti-selectin oligosaccharides (i.e., sialyl Lewis[X] analogs). Utilizing flow cytometry and immunohistochemistry, we will determine the time course of activation-inactivation of these adhesion molecules, their interaction among each other and their significance to reperfusion- and trauma-induced endothelial dysfunction. Employing intravital microscopy, we will directly visualize leukocyte-EC interactions at the level of the microvasculature (i.e., mesenteric venules). Further work will be directed toward studying cellular events in cultured ECs, and in investigating mechanisms of attenuation of reperfusion-induced increased adhesiveness of ECs and reduced NO generation. These findings should provide important basic insight into the pathophysiology and therapeutics of myocardial and splanchnic ischemia/reperfusion and traumatic shock. All of these are serious life threatening disorders, and knowledge of their pathophysiology provides important information to the clinician treating these conditions.