CGP71683 hydrochloride is primarily utilized in research settings to study the role of neuropeptide Y (NPY) receptors in various physiological processes. It acts as a selective antagonist for the NPY Y5 receptor, making it a valuable tool for investigating the mechanisms of appetite regulation and energy balance. Researchers employ it to explore potential therapeutic applications for conditions such as obesity and eating disorders, given its ability to modulate feeding behavior. Additionally, it is used in neuroscience studies to understand the involvement of NPY receptors in stress responses, anxiety, and depression. Its specificity for the Y5 receptor allows for targeted experiments, contributing to the development of novel pharmacological interventions.