the effect of theophylline on the kinetics of camp-dependent protein kinase catalytic subunit, camp, protein kinase inhibitor and their relationship in lung tissue

we have investigated the effect of theophylline on the kinetics of the catalytic subunit of protein kinase and related factors in lung tissue. the results show that the point of highest concentration of the c subunit of protein kinase which is active in casein phosphorylation is at 3h of incubation time, but in the presence of 100 ilg/ inl and 10µg/ml theophylline, this is shifted to i.s and 2.s hrs, respectively. also the maximum concentration of camp for the control is at 2.s h of incubation time, butin the treated samples shifts to 2.15 and lis hrs, respectively. inhibitor protein content also changes considerably in the presence of 10µg/ml theophylline. the results suggest an effect of theophylline on the function of camp-dependent protein kinase.