What is the Origin of Vasoactive Intestinal Polypeptide?

The name is purely descriptive, reflecting its initial discovery and its primary biological effects: "vasoactive" due to its influence on blood vessel diameter, "intestinal" due to its high concentration and initial isolation from the gut, and "polypeptide" describing its chemical structure as a short chain of amino acids. Its discovery provided early evidence of the profound integration between the nervous system and the endocrine system.

What is the Mechanism of Vasoactive Intestinal Polypeptide?

VIP exerts its diverse biological effects by binding to specific G protein-coupled receptors, primarily VPAC1 and VPAC2, on the surface of target cells throughout the body. Receptor activation leads to an increase in the intracellular concentration of cyclic AMP (cAMP), a crucial second messenger. This rise in cAMP mediates the relaxation of smooth muscle cells in the vasculature and the gut, resulting in vasodilation and increased secretory activity in the intestinal lining.

Vasoactive Intestinal Polypeptide

Meaning

Vasoactive Intestinal Polypeptide, widely known by its abbreviation VIP, is a neuro-peptide hormone that acts as a potent and broad-spectrum vasodilator, meaning it causes the relaxation and widening of blood vessels. VIP is extensively distributed throughout the central and peripheral nervous systems, as well as the gastrointestinal tract. It plays crucial roles in regulating regional blood flow, smooth muscle tone, and the secretion of water and electrolytes in the gut.