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H-89, Dihydrochloride
Activators & Inhibitors

H-89, Dihydrochloride #9844

Western Blotting

Western blot analysis of extracts from SKNMC cells, untreated or treated with indicated concentrations of H-89 for 30 minutes, followed by stimulation with 30 µM Forskolin for 10 minutes. The phosphorylation of CREB was detected using Phospho-CREB (Ser133) (87G3) Rabbit mAb #9198 (upper), CREB (48H2) Rabbit mAb #9197 was used as a loading control (lower). H-89 inhibition of Forskolin induced PKA phosphorylation on CREB at Ser133 is shown.

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H-89 is supplied as 5.19 mg powder. Store at or below -20ºC. Before usage, dissolve powder in 0.5 ml DMSO to make 20 mM H-89. For working concentrations of 10 μM-20 μM, dilute DMSO stock 1:2000 to 1:1000. Treat cells with the desired concentration for 30 minutes.


Store lyophilized or in solution at -20ºC, desiccated. Protect from light. In lyophilized form, the chemical is stable for 24 months. Once in solution, use within 3 months to prevent loss of potency. Aliquot to avoid multiple freeze/thaw cycles.

Molecular Weight:

519.28 g/mol



Molecular Formula:

C20H20BrN3O2S • 2HCl

H-89 is a potent selective inhibitor of cAMP dependent protein kinase (PKA). The in vitro IC50 of H-89 for PKA is approximately 50 nM and in vivo the inhibitiory effect on PKA substrate phosphorylation and related cellular functions range from 10 μM to 30 μM (1,2). In addition to PKA, H-89 also exhibits a moderate inhibitory effect on PKG and PKCμ, with IC50 in the 500 nM range (1,3). The inhibitory effect of H-89 is due to its competitive binding to the ATP pocket on the kinase catalytic subunit (4).

  1. Chijiwa, T. et al. (1990) J Biol Chem 265, 5267-72.
  2. Meja, K.K. et al. (2004) J Pharmacol Exp Ther 309, 833-44.
  3. Johannes, F.J. et al. (1995) Eur J Biochem 227, 303-7.
  4. Engh, R.A. et al. (1996) J Biol Chem 271, 26157-64.
For Research Use Only. Not For Use In Diagnostic Procedures.

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