High Quality Content by WIKIPEDIA articles! Vasoactive intestinal peptide also known as the vasoactive intestinal polypeptide or VIP is a peptide hormone containing 28 amino acid residues that is produced in many tissues of vertebrates including the gut, pancreas and suprachiasmatic nuclei of the hypothalamus in the brain. VIP stimulates contractility in the heart, causes vasodilation, increases glycogenolysis, lowers arterial blood pressure and relaxes the smooth muscle of trachea, stomach and gall bladder. In humans, the vasoactive intestinal peptide is encoded by the VIP gene.