Vasoactive intestinal peptide (VIP) is a 28-amino-acid neuropeptide in the glucagon/secretin superfamily, first isolated from intestinal tissue and now widely used as a laboratory research tool for studying GPCR signaling in cell-based systems. This overview covers its structure and in vitro pharmacology only.
Structure and Receptors
VIP shares sequence homology with PACAP and secretin. In cell culture models it binds VPAC1 and VPAC2 receptors, Gs-coupled receptors whose activation raises intracellular cAMP — a readout commonly measured in reporter and second-messenger assays.
Cell Culture Study Applications
- cAMP accumulation and reporter-gene assays for VPAC receptor pharmacology
- Receptor selectivity screening against related peptide ligands
- Signal-transduction pathway mapping in transfected and endogenous-expression cell lines
- Analytical characterization (HPLC purity, MS identity) as part of standard laboratory QC
Analytical Notes
Researchers typically confirm VIP identity by mass spectrometry and purity by RP-HPLC, and assess aggregation by orthogonal methods, before use in sensitive signaling assays where peptide quality directly affects reproducibility.
References
Harmar et al., IUPHAR review of VIP/PACAP receptors (Pharmacological Reviews); Laburthe & Couvineau, VPAC receptor molecular pharmacology literature.
Disclaimer: For laboratory research education only. Not for human consumption / research use only. No medical, therapeutic, dosing, or efficacy information is provided or implied.