Recent Advances in Endothelin Research on Cardiovascular and Endocrine Systems

Abstract

Recent advances in ET research on the cardiovascular and endocrine systems were reviewed. Considering the potent vasculotropic actions, strategically advantageous localization, and recent findings with the specific receptor antagonist, ET is Table 2. Effects of dehydration for 2 days on hematocrit, serum osmolarity, plasma levels of it-VP, plasma and neurohypophyseal levels of it-ET-1, density of NSG, and density of it-ET-1 in NSG potentially involved in the regulation of hemodynamic homeostasis and in the pathogenesis of essential and secondary hypertension. The mitogenic action on the vascular smooth muscle cells suggests its more chronic effect on the vascular structure. In addition to the hypertensinogenic aspects, the role of ET in maintaining blood pressure in a hypotensive condition should not be overlooked. The development of specific antagonists which block the action of locally operating ET in vivo will be a powerful tool in elucidating the pathophysiological significance of ET and will provide a new therapeutic approach for hypertension. The roles of ET in the endocrine system are also fascinating. Accumulating evidence supports the notion that ET modulates the secretion of pituitary and adrenal hormones. The mode of action is likely to be paracrine/autocrine rather than endocrine, although a possible role of circulating ET cannot be ruled out. The pathophysiological role of ET in the endocrine tissues remains to be clarified. The diversity of the action of ET on the blood pressure and endocrine functions provides further evidence of the complexity of the homeostatic mechanisms, leaving us an intriguing subject for future study.