Description
VIP (Vasoactive Intestinal Peptide) is an endogenous 28-amino acid neuropeptide. It is not a Khavinson bioregulator and not a small molecule tool, but a naturally occurring signaling peptide from the secretin peptide superfamily that includes secretin, PACAP, glucagon, GLP-1, GIP, and GHRH. As such, it is considered a specialty research peptide. It was first isolated from porcine intestine but is expressed throughout the nervous system, gastrointestinal tract, immune tissue, and pancreatic islets. VIP binds two Class B GPCRs — VPAC1 and VPAC2 — with comparable affinity, activating Gs-coupled cAMP signaling that phosphorylates CREB and drives downstream gene expression. Its circadian clock regulation angle is distinctive: Per1 and Per2 promoters contain CRE domains, meaning VIP-mediated CREB phosphorylation directly regulates molecular clock gene expression through VPAC2 receptor signaling — a research axis that no other compound in this catalog addresses.
Key Characteristics
- Circadian clock gene regulation through Per1/Per2 CRE domain activation is VIP’s most mechanistically distinctive research angle. VPAC2-mediated CREB phosphorylation directly drives molecular clock gene transcription; light-induced circadian synchronization requires VIP signaling, making it a research tool for studying neuroendocrine entrainment biology that no other compound in this catalog can replicate
- VPAC1 and VPAC2 receptor subtype selectivity creates two distinct research tracks. Researchers targeting circadian or pancreatic biology use VPAC2-selective approaches, while those studying intestinal epithelial and immune biology focus on VPAC1
- NF-κB inhibition alongside cAMP activation gives VIP a dual pro-survival and anti-inflammatory research profile — cAMP elevation supports cell survival and CREB-driven gene expression while NF-κB suppression reduces inflammatory mediator transcription; this simultaneous activation of one pathway and suppression of another is mechanistically unusual and shapes how inflammatory biology models using VIP are designed
- Structural membership in the secretin superfamily creates comparative research value alongside GLP-1, GIP, and GHRH. VIP shares ~68% sequence homology with PACAP and activates the same VPAC receptors. Researchers studying Class B GPCR pharmacology use VIP as an endogenous reference ligand alongside the incretin analogs already available in this catalog
- Short plasma half-life of minutes reflects its role as a local neuroendocrine and paracrine signal. This rapid clearance is a defining pharmacokinetic characteristic that shapes experimental protocol design, particularly for in vivo models requiring sustained receptor occupancy
Handling and Storage
Store as lyophilized powder under refrigeration, away from heat, moisture, and light. VIP degrades rapidly in plasma and under suboptimal storage conditions. Reconstitute immediately before use, use within the experimental session, and avoid repeated freeze-thaw cycles.
FAQs
What is VIP?
VIP (Vasoactive Intestinal Peptide) is an endogenous 28-amino acid neuropeptide from the secretin superfamily. It binds VPAC1 and VPAC2 receptors — Class B GPCRs — activating cAMP/CREB signaling while inhibiting NF-κB. Research contexts span circadian clock regulation, GI epithelial biology, pancreatic islet signaling, and immunomodulation. It is an endogenous peptide with a known receptor system, not a synthetic bioregulator.
How does VIP’s VPAC2-mediated circadian regulation work?
VIP is released from neurons in the suprachiasmatic nucleus — the brain’s circadian pacemaker. VPAC2 receptor activation elevates cAMP and drives CREB phosphorylation. Per1 and Per2, core components of the molecular clock, have CRE response elements in their promoters. CREB binding to these elements directly activates the Per gene transcription, synchronizing the molecular clock to external time cues. VIP signaling is required for normal light-induced circadian entrainment.
How does VIP relate to GLP-1 and other secretin superfamily members in research?
VIP, GLP-1, GIP, secretin, PACAP, and GHRH all belong to the same structural superfamily and signal through Class B GPCRs. VIP and PACAP share 68% sequence homology and activate the same VPAC receptors. GLP-1 acts through a distinct GLP-1 receptor but shares the cAMP/CREB signaling cascade. Researchers studying Class B GPCR pharmacology, incretin biology, or pancreatic islet signaling use VIP as an endogenous reference compound that illuminates receptor behavior and downstream pathway activity across the superfamily.
