Table 1 Effect of the protein kinase C (PKC) inhibitors staurosporine (ST, 10 nmol/l) and Gö6976 (100 nmol/l), and the PKA inhibitor H89 (100 nmol/l) on activity of recombinant cPKCα, nPKCϵ and PKA in vitro using myelin basic protein as kinase substrate
cPKCαnPKCϵPKA
InhibitorConcentration (nmol/min/g)%Concentration (nmol/min/g)%Concentration (pmol/min/mU)%
H2O standard309 (74)100771004.4 (1.7)100
DMSO control294 (46)9671 (11)964.7 (1.6)111
ST23 (3)**87 (1)**91.0 (0.6)*22
Gö6976163 (52)5361 (10)824.2 (1.5)98
H89217 (53)7144 (8)580.2 (0.1)**5
ST+H8923 (4)**86 (1)**80.1 (0.1)**2
Gö6976+H89107 (20)**3544 (5)600.4 (0.2)**10
  • PKC and PKA inhibitors were tested at concentrations at least 5- to 10-fold above their elsewhere reported IC50 for cPKCα and PKA, respectively, at which they did not affect bile flow and organic anion secretion in isolated perfused rat livers. For details see Materials and methods. Results are given as mean (SD) of protein kinase activity of four independent experiments (% of H2O standard).

  • *p<0.05, **p<0.01 vs DMSO control (0.1%,v/v), ANOVA post hoc test (Tukey).

  • DMSO, dimethylsulfoxide.