[Evidence of elevated soluble plasma thrombomodulin in atherosclerosis]

Thrombomodulin (TM) is a very efficient natural anti-thrombin glycoprotein expressed on the endothelial cell surface. Circulating soluble thrombomodulin is also detected by enzyme immunoassay in plasma and represents some fragments of membrane TM with various molecular weight. Plasma TM (TMp) levels are elevated in diseases associated with endothelium damage. We have explored TMp in patients with atheromatous disease and compared its level with others endothelial cell markers, particularly those who indicate cell activation, as tissue-type plasminogen activator (t-PA), inhibitor of plasminogen activator (PAI-1) and prostacyclin (PG12). Thirty seven patients with documented atheromatous artery disease were included in this study. They were not diabetics and their hepatic and renal functions were normal. Mean age was 71 +/- years. Routine serum parameters were checked out as well as others more specific for endothelium activation (TMp, PG12, PAI-1, t-PA) measured by enzyme immunoassay. Patients were classified according to three localizations of atheromatous involvement: - 15 patients with peripheral occlusive arteriopathy disease (POAD) - 6 with coronary artery disease (CAD); and 16 with polyvascular involvement (POLY). They were compared with 21 controls without any vascular lesions (mean age: 43 +/- 13 years). In controls TMp was 36 +/- 8 ng/ml without significant change according with age and sex. In patients whatever the localization of atheroma, TMp was found significantly higher: POAD = 51.3 +/- 19.7 ng/ml (p = 0.003); CAD = 49.2 +/- 15.4 ng/ml (p = 0.008); POLY = 49.6 +/- 17.2 ng/ml (p = 0.003). A positive correlation was pointed out in all patients between TMp and t-PA (p = 0.047), TMp and PG12 (p = 0.008). A positive correlation between TMp and t-PA (p = 0.034) was found only in the subgroup with POAD. In this study, there was no correlation between TMp and the following parameters: leucocytes, haemoglobin, cholesterol, HDL, LDL-cholesterol, Lp(a), fibrinogen.(ABSTRACT TRUNCATED AT 250 WORDS)