What Is VIP (Vasoactive Intestinal Peptide)? A Research Guide

VIP (Vasoactive Intestinal Peptide) is a 28-amino-acid neuropeptide of the secretin/glucagon peptide superfamily that signals through the class B G-protein-coupled receptors VPAC1 and VPAC2. It is studied in neuroendocrine, vascular, and immunomodulation research. This article is educational only. VIP is discussed here strictly as a research compound; it is for research use only (RUO) and is not for human use. Bolt Peptide does not sell VIP.

Quick facts

• Class: 28-amino-acid neuropeptide (secretin/glucagon peptide superfamily)
• Receptors: VPAC1 and VPAC2 (class B GPCRs)
• Research focus: neuroendocrine, immunomodulation, and vasodilation research

What is VIP?

Vasoactive intestinal peptide was first isolated from porcine intestine and characterized as a 28-amino-acid peptide. It belongs to the secretin/glucagon peptide superfamily, a group that also includes PACAP (pituitary adenylate cyclase-activating polypeptide) and GLP-1. In preclinical models, VIP is described as widely distributed across the central and peripheral nervous systems as well as peripheral tissues including the gastrointestinal tract, pancreas, cardiovascular system, and immune organs, where it has been studied as a putative neurotransmitter and neuroendocrine signaling molecule.

What does the research show?

In published reviews, VIP is characterized as a neuropeptide with broad, or “pleiotropic,” signaling roles in preclinical systems. Delgado and Ganea describe VIP as a 28-amino-acid neuropeptide distributed throughout the nervous system that has been examined for effects on cultured immune cells and in animal models of inflammatory and autoimmune processes — framed entirely as basic immunobiology research rather than as a treatment. The IUPHAR nomenclature review by Harmar and colleagues catalogues the pharmacology of VIP/PACAP receptors, confirming that VPAC1 and VPAC2 respond to VIP with high affinity and detailing the adenylyl-cyclase–coupled signaling these receptors engage. Separately, reviews of VIP and the VPAC2 receptor summarize preclinical work on glucose-dependent insulin-secretion pathways and pancreatic β-cell signaling in animal and cell models. None of this work establishes any outcome in humans.

Mechanisms studied in the lab

• VPAC1/VPAC2 GPCR signaling: VIP binds two class B G-protein-coupled receptors that couple primarily to G_s proteins.
• cAMP pathway: receptor activation increases adenylyl-cyclase activity and intracellular cAMP, a second-messenger cascade studied across multiple cell types.
• Immunomodulation (preclinical): in cell and animal models, cAMP-linked signaling has been examined for downstream effects on cultured immune-cell activity.

Research status

VIP is discussed only as a research-use-only (RUO) compound. It is not approved by the FDA for the diagnosis, treatment, cure, or prevention of any condition, and it is not a dietary supplement. All properties described above come from in vitro and animal studies and do not predict any effect in humans. VIP is not for human use.

Related research peptides

Bolt Peptide does not carry VIP, but you can browse our full research peptide catalog for available compounds. For related reading on other neuropeptides studied in the lab, see our guides on KPV, a peptide studied in anti-inflammatory research, and PT-141, another melanocortin/neuropeptide research compound.

FAQ

Is VIP the same as PACAP? No. They are distinct peptides within the same secretin/glucagon superfamily. Both bind the VPAC1 and VPAC2 receptors with high affinity, while PACAP additionally binds a PACAP-selective PAC1 receptor.

Which receptors does VIP act on? In the research literature, VIP signals primarily through two class B GPCRs, VPAC1 and VPAC2, coupled to adenylyl cyclase and cAMP generation.

Does Bolt Peptide sell VIP? No. This article is educational. VIP is described here only as a research compound and is not offered for sale or for human use.

References

1. Delgado M, Ganea D. Vasoactive intestinal peptide: a neuropeptide with pleiotropic immune functions. Amino Acids. 2013.
2. Harmar AJ, et al. Pharmacology and functions of receptors for VIP and PACAP: IUPHAR Review 1. Br J Pharmacol. 2012.
3. Hou X, et al. VIP and its receptor VPAC2 in type 2 diabetes research. Front Endocrinol. 2022.

For research use only. Not for human or veterinary use; not a drug, food, or supplement. Bolt Peptide does not sell VIP. Statements have not been evaluated by the FDA.