The purpose of this study is to explore the clinical value of plasma endothelin(EH)in EssentialHypertension(Eh)and coronary artery disease (CAD)Methods:the levels of plasma ETwere measured byradioimmunoassay at different stages in 42 EH and 45 CAD and 45 healthy personsResults:the results showedthat plasma ET levels in patients with EH in the 3rd stage and the patients withCAD in heart failure weresignificantly higher than those in the healthy.The concentration of plasma ET atthe 3rd EH stage and patientswith CAD in heart failure was 90.10±21.76pg/ml(P<0.01)and 85.33±16.07pg/ml(P<0.01).ET levels in patientswith EH stages Ⅰ

Ⅱ and patients with CAD in function compensation stage was 46.9±50.02pg/ml(P>0.05)and48.88±4.72pg/ml(P>0.05).It is suiggested that the elevation of ET may contribute to the pathophysiological changes in patients with EH or CAD.