Expression of endothelial protein C receptor and thrombomodulin in human coronary atherosclerotic plaques.

Background. The expression of selected genes in human coronary atherosclerotic plaques may help to clarify the evolution of atherogenesis and the causes of thrombogenesis on some fissured plaques. The aim of this study was to analyze the expression of the genes known to participate in inflammation and hemostasis: thrombomodulin and endothelial protein C receptor, E- and P-selectin, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), tissue factor and plasminogen activator inhibitor-1 (PAI-1). Methods. RNA was extracted and reverse-transcribed from 27 atherectomized human coronary atherosclerotic plaques. The genes were specifically amplified together with a housekeeping gene. Results. Thrombomodulin was not expressed in the 8/27 plaques from which RNA could be obtained. The levels of expression of tissue factor, ICAM-1, P- and E-selectin, and PAI-1 were low, whereas those of endothelial protein C receptor and VCAM-1 were high. Conclusions. RNA may be extracted from ex vivo atherosclerotic plaques. In addition to anticoagulation, endothelial protein C receptor may play an important inflammation-related role in plaque development.