sb203580 hcl is a specific inhibitor of p38-mapks with ic50 value of 0.6 μm [1].sb203580 is an inhibitor of p38-mapkα and p38-mapkβ. in neonatal myocytes, sb203580 prevented p38-mapk from activating mapkapk2 with ic50 value of 70 nm. it also significantly suppressed mapkapk2 activation in by il-1, osmotic stress or arsenite in kb cells. in neonatal rat ventricular myocytes, sb203580 inhibited jnk activity of activating c-jun with ic50 value of 3-10 μm. besides that, sb203580 affected the phosphorylation of small heat shock proteins caused by mapkapk2. it inhibited the il-1-, chemical- or osmotic stress-stimulated hsp27 phosphorylation with ic50 value of < 1μm in kb cells [1, 2].
[1] cuenda a, rouse j, doza y n, et al. sb 203580 is a specific inhibitor of a map kinase homologue which is stimulated by cellular stresses and interleukin-1. febs letters, 1995, 364(2): 229-233.
[2] clerk a, sugden p h. the p38-mapk inhibitor, sb203580, inhibits cardiac stress-activated protein kinases/c-jun n-terminal kinases (sapks/jnks). febs letters, 1998, 426(1): 93-96.
