THROMBOMODULIN AND SMOKING

Recently Blann [l] reported an increase in serum levels of von Willebrand factor antigen in smokers immediately after they had smoked two cigarettes. The von Willebrand factor is a specific endothelial constituent and its increased release indicates endothelial injury. To further investigate the possibility of endothelial damage caused by smoking, we studied the activation of thrombomodulin, another endothelial cell marker [2,3]. Thrombomodulin levels were assessed by EIA (Thrombomodulin-Asserachrom, Diagnostica Stago, France) immediately before and after the smoking of two filtered medium tar cigarettes of trade mark ‘Sparta’ in 12 male smokers. Statistical analysis by Wilcoxon rank sum test did not reveal any release of thrombomodulin (Table 1). Thrombomodulin is produced by endothelial cells and is bound to their surface. It exerts antithrombotic activity by mediating protein C activa-