The p38-MAPK inhibitor, SB203580, inhibits cardiac stress-activated protein kinases/c-Jun N-terminal kinases (SAPKs/JNKs)

FEBS Lett. 1998 Apr 10;426(1):93-6. doi: 10.1016/s0014-5793(98)00324-x.


SB203580 is a recognised inhibitor of p38-MAPKs. Here, we investigated the effects of SB203580 on cardiac SAPKs/JNKs. The IC50 for inhibition of p38-MAPK stimulation of MAPKAPK2 was approximately 0.07 microM, whereas that for total SAPK/JNK activity was 3-10 microM. SB203580 did not inhibit immunoprecipitated JNK1 isoforms. Three peaks of SAPK/JNK activity were separated by anion exchange chromatography, eluting in the isocratic wash (44 kDa), and at 0.08 M (46 and 52 kDa) and 0.15 M NaCl (54 kDa). SB203580 (10 microM) completely inhibited the 0.15 M NaCl activity and partially inhibited the 0.08 M NaCl activity. Since JNK1 antibodies immunoprecipitate the 46 kDa activity, this indicates that SB203580 selectively inhibits 52 and 54 kDa SAPKs/JNKs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Newborn
  • Calcium-Calmodulin-Dependent Protein Kinases / antagonists & inhibitors*
  • Enzyme Activation / drug effects
  • Enzyme Inhibitors / pharmacology*
  • Imidazoles / pharmacology*
  • JNK Mitogen-Activated Protein Kinases
  • Mitogen-Activated Protein Kinases*
  • Myocardium / enzymology
  • Pyridines / pharmacology*
  • Rats
  • p38 Mitogen-Activated Protein Kinases


  • Enzyme Inhibitors
  • Imidazoles
  • Pyridines
  • Calcium-Calmodulin-Dependent Protein Kinases
  • JNK Mitogen-Activated Protein Kinases
  • Mitogen-Activated Protein Kinases
  • p38 Mitogen-Activated Protein Kinases
  • SB 203580