Used primarily in neuroscience and pharmacology research to study pain modulation and the endogenous opioid system. It acts as an agonist for opioid receptors, particularly the delta-opioid receptor, making it valuable for investigating mechanisms of analgesia and addiction. Its role in regulating pain perception and emotional responses is explored in experimental models to understand its potential therapeutic applications. Additionally, it is utilized in biochemical assays to study peptide-receptor interactions and signal transduction pathways. Its natural occurrence in the body also makes it a key focus in studies on stress, mood disorders, and neurodegenerative diseases.