VIP (vasoactive intestinal peptide) A peptide hormone secreted by endocrine cells of the upper part of the small intestine in response to the entry of partially digested food from the stomach. VIP, along with secretin, stimulates the pancreas to produce a thin watery secretion containing bicarbonate. This raises the pH in the intestine in preparation for secretion of pancreatic enzymes. VIP also inhibits gastric secretion, occurs as a neuropeptide in central nervous tissue, where it functions as a cotransmitter, and has a range of other physiological roles.

VIP • abbr. ∎  very important person. ∎  Biochem. vasoactive intestinal polypeptide (or peptide), a substance which acts as a neurotransmitter, esp. in the brain and gastrointestinal tract.

VIP (vasoactive intestinal peptide) n. a peptide hormone and neurotransmitter found widely throughout the central nervous system and intestinal tract. Its many actions include vasodilatation of blood vessels in the gut and reduction of stomach acid secretion. Large amounts cause severe diarrhoea (see VIPoma).

VIP Med. vasoactive intestinal peptide
• very important person