VIP (vasoactive intestinal peptide) is a 28-amino acid neuropeptide that functions as a multifunctional signaling molecule with diverse physiological roles 1. The primary function of VIP is vasodilation, causing relaxation of blood vessels through endothelium-dependent mechanisms 2. VIP exerts its effects by binding to specific receptors and activating multiple intracellular signaling pathways, including cAMP/PKA, RhoA-GTPase, PLC, and MAPK cascades 3. The peptide activates adenylyl cyclase-mediated cAMP signaling and modulates cellular calcium levels 3. VIP gene expression is regulated at multiple levels, including transcriptional control through cis-regulatory elements and post-transcriptional mRNA stabilization 45. The gene contains seven exons with complex regulatory mechanisms involving both ubiquitous and neuron-specific transcription factors 64. VIP has significant clinical relevance, functioning as an autocrine growth factor in non-small cell lung cancer and being involved in cerebrovascular pathophysiology following subarachnoid hemorrhage, where CGRP levels are reduced 57. The peptide also plays important roles in sexual arousal, neuroendocrine functions, and immune cell modulation, making it a critical mediator of multiple physiological processes 83.