Neutrophil adherence to activated saphenous vein and mammary endothelium after graft preparation.
BACKGROUND
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.


METHODS
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.


RESULTS
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.


CONCLUSIONS
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.
Department of Medicine III, Martin Luther-University, Halle-Wittenberg, Germany.
Axel
A
Schlitt
Diethard
D
Pruefer
Ute
U
Buerke
Martin
M
Russ
Manfred
M
Dahm
Hellmut
H
Oelert
Karl
K
Werdan
Michael
M
Buerke
D002448:Cell Adhesion; D001026:Coronary Artery Bypass; D004106:Dilatation; D004730:Endothelium, Vascular; D006801:Humans; D066298:In Vitro Techniques; D008323:Mammary Arteries / Q000187:drug effects / Q000502:physiology / Q000637:transplantation; D009504:Neutrophils / Q000502:physiology*; D010208:Papaverine / Q000494:pharmacology; D011300:Preoperative Care; D012501:Saphenous Vein / Q000187:drug effects / Q000502:physiology / Q000637:transplantation; D013917:Thrombin / Q000494:pharmacology; D014665:Vasodilator Agents / Q000494:pharmacology
D014665:Vasodilator Agents; D010208:Papaverine; D013917:Thrombin