Peptide VIP is a Neuropeptide that is widely distributed in the central and peripheral nervous systems; Peptide VIP is a vasodilator, bronchodilator and smooth muscle relaxant. Peptide VIP modulates the activity of many immune system cell types. VIP is a mitogen for embryonic sympathetic neurons and its neuroprotective actions are mediated by the release of activity-dependent neurotrophic factors from glial cells.