Hypertension Associated with Reduced Plasma Thrombomodulin Levels and a Hypercoagulable State in Rats

The plasma thrombomodulin (TM) level, an indicator of systemic endothelial cell damage, was measured in spontaneously hypertensive rats (SHR), deoxycorticosteron acetate (DOCA)-induced hypertensive rats and normotensive Wistar-Kyoto (WKY) rats to clarify its changes in hypertension. Plasma TM levels, measured by enzyme-linked immuno-sorbent assay, decreased with aging (5-20-weeks-old) in both SHR and WKY, and they were lower in SHR than age-matched WKY in all ages examined. Deoxycorticosteron acetate-induced hypertensive WKY also showed decreased TM levels compared with normotensive WKY. Accelerated coagulation and fibrinolysis shown by the increases in thrombin-antithrombin complex (TAT) and D-dimer levels were observed in both groups of hypertensive rats. These results suggest that hypertension may decrease plasma TM levels and induce a hypercoagulable state in rats.