Adrenomedullin and diabetes mellitus

Adrenomedullin (AM) is a novel 52 amino acid peptide hormone, originally is olated from human pheochromocytoma. AM acts as a local autocrine and/or par acrine vasoactive hormone and has vasodilator and blood pressure lowering p roperties. AM as a vasodilative molecule protects the vascular wall but its exact role is still uncertain. AM is considered to play an important endoc rine role in various tissues in maintaining electrolyte and fluid homeostas is. Its plasma concentration in healthy conditions is low. In hypertension, chronic renal failure and congestive heart failure its plasma concentratio n increases in a parallel manner with the severity of the disease. It is as sumed that this peptide plays an important role in physiological and pathol ogical conditions compensating the effects of vasoconstrictive molecules. I nvestigations have proven that in diabetic angiopathies the levels and prod uction of vasoconstrictive factors and AM are increased, while other relaxi ng substances such as nitric oxide (NO) are decreased. It is still uncertai n whether the increased release of AM is a compensatory mechanism or a coin cidental event. Although the precise role of AM in the pathogenesis of diab etic complications is still to be elucidated, the altered concentration of AM in diabetes could indicate a certain interaction between AM induction an d vascular function. Hence, the induction of vascular AM can be a new targe t of therapeutic approach to diabetic complications. Copyright (C) 2001 Joh n Wiley & Sons, Ltd.