VIP: Dosage, Benefits & Research Guide
What is VIP?
VIP (Vasoactive Intestinal Peptide) is a 28-amino acid neuropeptide belonging to the secretin/glucagon superfamily, originally isolated from porcine duodenum by Said and Mutt in 1970. VIP signals through two G-protein coupled receptors, VPAC1 and VPAC2, both of which activate adenylyl cyclase to elevate intracellular cAMP. Widely distributed throughout the central and peripheral nervous systems, VIP functions as a neurotransmitter and neuromodulator with roles in vasodilation, smooth muscle relaxation, exocrine secretion, circadian rhythm regulation, and neuroprotection. Research by Delgado et al. (2004) in Pharmacological Reviews comprehensively characterized VIP's anti-inflammatory properties, demonstrating suppression of TNF-alpha, IL-6, and IL-12 in activated macrophages while upregulating the anti-inflammatory cytokine IL-10. Studies published in the Journal of Neuroscience by Bhatt et al. showed that VIP protected hippocampal neurons from excitotoxic and oxidative damage through VPAC2-mediated cAMP/PKA signaling. Abad et al. in Annals of the New York Academy of Sciences reported that VIP administration ameliorated experimental autoimmune encephalomyelitis in murine models, suggesting therapeutic potential in neuroinflammatory conditions. Additional research has shown VIP regulates the suprachiasmatic nucleus master clock, influencing circadian output. Compared to PACAP (Pituitary Adenylate Cyclase-Activating Polypeptide), which shares significant structural homology and receptor overlap, VIP has higher selectivity for VPAC receptors and lower affinity for PAC1 receptors. This makes VIP preferred for research specifically targeting VPAC-mediated pathways rather than the broader PAC1-dependent neuroprotective signaling. VIP is sensitive to degradation. Store lyophilized at -20°C. Reconstitute with bacteriostatic water and store at 2-8°C, using within 2-3 weeks. Studied by neuroscientists, immunologists, chronobiologists, and pulmonary researchers investigating airway smooth muscle regulation.
VIP Research Applications
In published and preclinical research, VIP has been studied across the following areas:
- Cognitive focus and neuroprotection
- Vasodilation and blood flow
- Immune modulation studies
- Circadian rhythm regulation
VIP in Research: Reconstitution & Study Concentrations
VIP is supplied as a lyophilized powder. For laboratory research it is reconstituted with bacteriostatic or sterile water; the solvent volume sets the working concentration. Published studies select concentrations specific to the assay or model system — there is no human dose, as VIP is not approved for human use. Researchers should reference the primary literature for the model in question and document the exact lot COA.
Worked example: a 10mg vial reconstituted with 2 mL of bacteriostatic water yields 5.00 mg/mL.
Open the reconstitution calculator