Vasoactive Intestinal Peptide (VIP) is a neuropeptide that plays a crucial role in various physiological processes. It is primarily produced in the intestines and the central nervous system. VIP is known for its ability to relax smooth muscles, stimulate the secretion of digestive enzymes, and enhance blood flow to the gastrointestinal tract. In addition to its digestive functions, VIP also has effects on the immune system and the regulation of circadian rhythms. It acts as a neurotransmitter, influencing the activity of other hormones and neurotransmitters, thereby contributing to overall homeostasis in the body.