endoteeliinien

Endoteeliinien, also known as endothelin-1 (ET-1), is a potent vasoconstrictor peptide hormone primarily produced by endothelial cells lining blood vessels. It plays a crucial role in regulating vascular tone, blood pressure, and fluid balance within the body. As a member of the endothelin family, which includes endothelin-2 and endothelin-3, ET-1 is the most extensively studied and biologically active form.

Endoteeliinien is synthesized as a precursor protein, preproendothelin-1, which undergoes enzymatic processing to form big endothelin-1 before being converted into the mature 21-amino acid peptide. This conversion is mediated by the enzyme endothelin-converting enzyme (ECE). Once released, ET-1 binds to two distinct G-protein-coupled receptors: ETA and ETB, which mediate its diverse physiological effects.

The primary function of ET-1 is vasoconstriction, where it binds to ETA receptors on vascular smooth muscle cells, leading to increased intracellular calcium levels and contraction of the vessel walls. This action helps regulate blood pressure and peripheral resistance. ET-1 also promotes cell proliferation, fibrosis, and inflammation, contributing to pathological processes such as hypertension, atherosclerosis, and heart failure. Additionally, it influences renal function by modulating glomerular filtration rate and sodium excretion.

Dysregulation of endothelin signaling has been implicated in various cardiovascular and renal disorders. Elevated levels of ET-1 are associated with conditions like pulmonary hypertension, where excessive vasoconstriction and remodeling of pulmonary arteries occur. Therapeutic strategies targeting the endothelin system, such as endothelin receptor antagonists, are being explored to treat these diseases.

Endoteeliinien is also involved in non-vascular functions, including neuroprotection, immune modulation, and bone remodeling, highlighting its broad physiological significance. Research continues to elucidate its complex roles and potential as a therapeutic target in multiple pathological states.