Adrenomedullin is a peptide hormone involved in vascular regulation, blood flow control, endothelial signaling, fluid balance, and cardiovascular adaptation. The hormone functions primarily as a vasodilatory signaling molecule that helps regulate vascular tone and maintain circulatory stability during changing physiological conditions.
Adrenomedullin influences smooth muscle relaxation, endothelial protection, renal blood flow, sodium balance, and microvascular circulation. It also contributes to inflammatory signaling, oxidative stress adaptation, and regulation of tissue perfusion during metabolic or hemodynamic stress. Through these actions, the hormone helps coordinate communication between endothelial tissues, kidneys, heart, and circulatory systems.
Adrenomedullin is produced by endothelial cells, vascular smooth muscle cells, adrenal tissues, heart tissue, kidneys, lungs, and numerous additional organs. The hormone is synthesized as a larger precursor peptide that undergoes enzymatic processing to form the biologically active molecule.
Production increases during conditions associated with vascular stress, inflammatory signaling, hypoxia, oxidative stress, and altered circulatory demand. Because many tissues can synthesize adrenomedullin locally, the hormone functions through both endocrine and paracrine communication pathways.
Adrenomedullin production is regulated by inflammatory cytokines, hypoxia, oxidative stress pathways, shear stress, endotoxin exposure, and cardiovascular signaling systems. Hormonal communication involving angiotensin II, natriuretic peptides, and nitric oxide pathways also influences secretion dynamics.
The hormone acts through calcitonin receptor-like receptor systems associated with receptor activity-modifying proteins that activate cyclic AMP signaling pathways and vascular relaxation mechanisms. Interactions with nitric oxide signaling and endothelial protective pathways contribute to regulation of vascular tone and tissue perfusion. Through these integrated cardiovascular signaling systems, adrenomedullin coordinates endothelial adaptation, vascular relaxation, renal communication, and circulatory homeostasis.
Widely expressed vasoactive peptide regulating vascular tone and fluid balance.
