VIP

VIP is a 28-residue linear peptide with no disulfide bridges. The molecule binds two class B G-protein-coupled receptors — VPAC1 and VPAC2 — both engaging Gs-coupled cAMP signaling cascades documented across the published literature. Tissue expression of VPAC1 and VPAC2 differs substantially, supporting research that uses VIP to dissect tissue-specific receptor contributions to downstream physiology. Pharmacokinetic descriptors documented in published animal-model investigations include rapid plasma clearance and a very short systemic half-life under standard parenteral paradigms — a property that has driven research interest in stabilized VIP analogs. Interaction profile in the literature spans VPAC1/VPAC2 cAMP activation, smooth-muscle-cell signaling, and immunomodulator-pathway research in lymphocyte and macrophage cultures. All activity descriptors here are framed as documented in published work. Structural confirmation is established by mass spectrometry and HPLC-validated purity on each Certificate of Analysis.

Experimental domains documented in the published literature include VPAC1 and VPAC2 receptor-binding affinity studies, structure-activity investigations probing the role of individual residues in receptor engagement, neuroendocrine signaling research, smooth-muscle relaxation pathway studies in tissue-bath preparations, immunomodulator-pathway investigations in lymphocyte and macrophage cultures, comparative work alongside related secretin-family peptides (PACAP, secretin, GHRH, glucagon), and screening assays for VPAC-receptor-selective ligand discovery. Investigators have also characterized VIP in studies of receptor internalization kinetics and in antagonist-development paradigms targeting the VPAC receptors. Use in laboratory research extends to mechanism-elucidation paradigms where the molecule serves as a foundational neuropeptide reference for the secretin family. The reference standard is supplied for these and equivalent in-vitro and animal-model experimental contexts only, with no associated guidance for human, clinical, or veterinary application.

Each lot is characterized by reverse-phase HPLC for chromatographic purity and by mass spectrometry for molecular-ion confirmation against the C147H237N43O43S empirical formula. Purity is reported as an HPLC-area percentage on the Certificate of Analysis distributed with every lot, alongside the molecular-weight match within instrument tolerance. Peptide content where applicable is determined by amino-acid analysis or nitrogen-content assay following the analytical method specified on the COA. Residual solvent and water content are reported categorically when these parameters are part of the lot's release specification. The COA records the lot identifier, manufacturing date, and analytical method versions used, providing a traceable provenance chain from synthesis through release. Researchers requiring batch-level analytical detail should reference the COA distributed with the supplied material.

For laboratory storage, the lyophilized reference standard should be held at −20°C in its sealed, light-protected container until ready for analytical use. Allow vials to equilibrate to ambient temperature before opening to avoid moisture condensation on the lyophile. Reconstitution for in-vitro experimental use is typically performed in bacteriostatic water or a researcher-selected buffer compatible with the downstream assay; once reconstituted, store the working solution at 2–8°C and characterize stability in the relevant buffer prior to extended storage. VIP exhibits known sensitivity to enzymatic degradation in many biological buffers — assay-specific stability characterization with appropriate protease inhibitors is recommended. Avoid repeated freeze-thaw cycles of reconstituted material. These handling parameters reflect general best-practice for lyophilized peptide reference standards and do not constitute preparation guidance for human or veterinary application.