VIP (vasoactive intestinal peptide) is involved in the VIP biosynthetic pathways. It also acts as a neurotransmitter in neural tissues and works in the relaxation of smooth muscle, stimulation of intestinal water and electrolyte secretion and release of insulin, glucagon and several anterior pituitary hormones. It participates in vasodilation. It acts as a potent agonist of the calcitonin receptor CALCR, with similar efficacy as calcitonin.
