Nω-propyl-L-Arginine (N5-) is primarily utilized in biochemical research as a selective inhibitor of nitric oxide synthase (NOS) enzymes. It is particularly effective in distinguishing between the different isoforms of NOS, such as neuronal NOS (nNOS), inducible NOS (iNOS), and endothelial NOS (eNOS). This specificity makes it a valuable tool in studies aimed at understanding the role of nitric oxide in various physiological and pathological processes, including neurotransmission, immune response, and vascular function. Additionally, it is employed in pharmacological research to explore potential therapeutic strategies for conditions associated with dysregulated nitric oxide production, such as inflammation, neurodegenerative diseases, and cardiovascular disorders. Its application extends to in vitro and in vivo experiments, providing insights into the complex signaling pathways mediated by nitric oxide.