Vasoactive Intestinal Peptide (VIP) is a 28-amino-acid neuropeptide that functions as a neuromodulator and neurotransmitter. It is widely distributed throughout the central and peripheral nervous systems, as well as the gastrointestinal tract.
### Mechanisms of Action
VIP binds to the VPAC1 and VPAC2 receptors, leading to the activation of adenylate cyclase and an increase in intracellular cAMP. This signaling cascade results in smooth muscle relaxation, vasodilation, and the modulation of immune cell function.
### Research Applications
* **Immunomodulation:** VIP has demonstrated potent anti-inflammatory effects in vitro, shifting the immune response from a Th1 (pro-inflammatory) to a Th2 (anti-inflammatory) profile.
* **Pulmonary Function:** Research models of pulmonary hypertension utilize VIP to study its vasodilatory effects on the pulmonary vasculature.
* **Neuroprotection:** VIP is being investigated for its ability to protect neurons from oxidative stress and excitotoxicity.
*Disclaimer: VIP is sold strictly for laboratory research use only. Not for human consumption.*