Schlitt Axel, Pruefer Diethard, Buerke Ute, Russ Martin, Dahm Manfred, Oelert Hellmut, Werdan Karl, Buerke Michael
Department of Medicine III, Martin Luther-University, Halle-Wittenberg, Germany.
Ann Thorac Surg. 2006 Apr;81(4):1262-8. doi: 10.1016/j.athoracsur.2005.09.073.
Interaction of circulating leukocytes and vascular endothelium plays an important role in vasoconstriction, endothelial dysfunction, and vascular injury. Dilation procedures of grafts before coronary artery bypass graft surgery might lead to vascular injury and subsequent bypass graft disease.
We analyzed in vitro the adherence of fluorescence-labeled polymorphonuclear neutrophils (PMNs) to endothelium of human saphenous vein grafts or internal mammary artery grafts after stimulation with thrombin (0.5 to 2 U/mL) or dilating procedures. Furthermore, we investigated endothelial function of prepared grafts.
Thrombin stimulation resulted in a dose-dependent increase of PMN adherence to the endothelium of saphenous vein and internal mammary artery, which was attenuated by the selectin-blocking carbohydrate fucoidin or anti-P-selectin monoclonal antibody. Mechanical dilation of saphenous vein or internal mammary artery led to a marked increase in PMN adherence (65 +/- 5 versus 5 +/- 3 PMN/mm2; p < 0.01), which was significantly attenuated by fucoidin or anti-P-selectin monoclonal antibodies. Treatment of internal mammary artery with the vasodilator papaverine led to a marked increase of PMN adherence (59 +/- 8 versus 12 +/- 4 PMN/mm2; p < 0.01) when papaverine was administered directly into the vessel. However, external treatment with papaverine did not affect PMN adhesion. Endothelial dysfunction was observed in dilated venous grafts and in arterial grafts internally treated with papaverine; in contrast, external treatment did not affect endothelial function.
This study showed that mechanical or pharmacologic dilation of venous or arterial coronary grafts, usually performed before anastomosis of aortocoronary bypass grafts, led to increased selectin-mediated PMN adhesion on vascular endothelium and subsequent endothelial dysfunction.
循环白细胞与血管内皮的相互作用在血管收缩、内皮功能障碍及血管损伤中起重要作用。冠状动脉旁路移植手术前对移植物进行扩张操作可能导致血管损伤及随后的旁路移植血管病变。
我们在体外分析了荧光标记的多形核中性粒细胞（PMN）在凝血酶（0.5至2 U/mL）刺激或扩张操作后与人隐静脉移植物或乳内动脉移植物内皮的黏附情况。此外，我们研究了制备好的移植物的内皮功能。
凝血酶刺激导致PMN对隐静脉和乳内动脉内皮的黏附呈剂量依赖性增加，而选择素阻断性碳水化合物岩藻依聚糖或抗P-选择素单克隆抗体可减弱这种增加。隐静脉或乳内动脉的机械扩张导致PMN黏附显著增加（65±5对5±3个PMN/mm²；p<0.01），岩藻依聚糖或抗P-选择素单克隆抗体可显著减弱这种增加。当将血管扩张剂罂粟碱直接注入乳内动脉血管时，可导致PMN黏附显著增加（59±8对12±4个PMN/mm²；p<0.01）。然而，罂粟碱的外部处理并不影响PMN黏附。在扩张的静脉移植物和经罂粟碱内部处理的动脉移植物中观察到内皮功能障碍；相比之下，外部处理不影响内皮功能。
本研究表明，通常在主动脉冠状动脉旁路移植吻合术前对静脉或动脉冠状动脉移植物进行的机械或药物扩张，会导致选择素介导的PMN在血管内皮上的黏附增加及随后的内皮功能障碍。
