Vasoactive Intestinal Peptide (VIP) is widely used in research to study its role as a neurotransmitter and hormone. It is particularly significant in understanding the regulation of smooth muscle relaxation, blood flow, and secretion in various organs. VIP is also investigated for its potential therapeutic applications in conditions like asthma, erectile dysfunction, and inflammatory diseases due to its anti-inflammatory and immunomodulatory properties. Additionally, it plays a role in neuroprotection and is studied in the context of neurodegenerative disorders such as Alzheimer's disease. Its ability to modulate cell proliferation and apoptosis makes it a subject of interest in cancer research as well.