DIET-INDUCED HYPERCHOLESTEROLEMIA INCREASES ENDOTHELIN-1 RELEASE BY AORTIC ENDOTHELIAL-CELLS

Our previous studies demonstrated the morphological heterogeneity of e ndothelial cells (ECs) and the emergence of large multinucleated ECs i n human and animal atherosclerotic lesions. To investigate the functio nal alteration of ECs in diet-induced atherosclerosis, immunoreactive endothelin-1 (irET-1) release by ECs of the rabbit aorta was correlate d with scanning electron microscopy. Rabbits were fed a cholesterol di et for 12 weeks: by scanning electron microscopy, the area of ECs in t he aorta increased in the hypercholesterolemic (HC) group as atheroscl erosis progressed. Cultured ECs of the HC group released significantly more irET-1 than ECs of the control. The plasma irET-1 level was also elevated in the HC group. The results obtained suggest that accelerat ed secretion of ET-1 by ECs contributes to the development of atherosc lerotic vascular lesions.