Figure 2.
Effect of inhibition of protein kinase A on dbcAMP-stimulated decrease in agonist-stimulated MAPK activity. Lacrimal gland acini were incubated with the PKA inhibitor H89 (10−5 and 5 × 10−5 M) for 10 minutes before the addition of dbcAMP (10−3 M) for 30 minutes. No stimulus, the cholinergic agonist carbachol (Cch 10−4 M), or the growth factor EGF (10−7 M) was then added for 5 minutes. Western blot analysis was performed using an antibody against phosphorylated p42/p44 MAPK. Data are mean ± SEM from three independent experiments (A). *Significant difference from basal. #Significant difference from MAPK activity in the presence of agonist alone. $Significant difference from MAPK activity in the presence of agonist and dbcAMP. Representative blot (B).