VIP (Vasoactive Intestinal Peptide) is a neuropeptide that acts as a neurotransmitter and immunomodulator, involved in regulating smooth muscle activity, blood flow, and immune responses.

VIP (Vasoactive Intestinal Peptide) is a neuropeptide that acts as a neurotransmitter and immunomodulator, involved in regulating smooth muscle activity, blood flow, and immune responses.