SB 203580 hydrochloride is widely used in biomedical research as a selective inhibitor of p38 MAP kinase, a key enzyme involved in cellular stress responses. Its primary application is in studying signaling pathways related to inflammation, apoptosis, and cell differentiation. Researchers utilize it to investigate the role of p38 MAPK in various diseases, including cancer, autoimmune disorders, and neurodegenerative conditions. It is also employed in drug discovery to evaluate potential therapeutic targets by modulating p38 activity. Additionally, SB 203580 hydrochloride is used in vitro to explore its effects on cytokine production and immune cell function, providing insights into inflammatory processes. Its specificity and efficacy make it a valuable tool in understanding cellular mechanisms and developing novel treatments.