Localisation of endothelin-1 and its receptors in vascular tissue as seen at the electron microscopic level.

Since the discovery of endothelin in vascular endothelial cells and its pivotal role in vascular physiology (Yanagisawa and colleagues), a number of studies have focused on the localisation of this vasoconstrictor peptide in human and animal vascular tissue, largely in endothelial cells. Various vascular beds have been the subject of research in normal and pathophysiological conditions, for example in neonates, during ageing, pregnancy, hypertension, diabetes, heart failure, experimental metastases and neurological disorders. These studies have revealed the presence of endothelin in the blood vessel wall, suggesting the involvement of this peptide in vascular physiology in health and disease. This chapter reviews studies on the distribution of endothelin-1 (ET-1) and its receptors (ET(A) and ET(B)) in vascular tissue with emphasis on their ultrastructural localisation.