[Leu5]-Enkephalin, amide is primarily used in research to study the opioid system and its effects on pain modulation. It acts as an agonist for opioid receptors, making it valuable for investigating mechanisms of pain relief and the role of endogenous opioids in the body. This compound is also utilized in neuroscience to explore its potential in regulating mood, stress responses, and addiction pathways. Additionally, it serves as a tool in pharmacological studies to develop new analgesic drugs with improved efficacy and reduced side effects. Its stability and specificity make it a useful peptide in biochemical assays and receptor-binding experiments.