[Effect of cyclic adenosine-3,5-monophosphate and its dibutyryl analog on macromolecule biosynthesis in actively proliferating cells].

The effect of cAMP and its dibutyryl analogue on the biosynthesis of nucleic acids and protein in active proliferating cells was studied. It was shown that cAMP (10(-3)--10(-4)M) caused stimulation of the biosynthesis of DNA and RNA in Ehrlich's ascites carcinoma (EAC) cells and intensification of collagen biosynthesis in the chick embryo cartilage tissue in vitro. Dibutyryl -- cAMP (10(-3)--10(-4)M) has an inhibitory action on the biosynthesis of macromolecules both in EAC cells and embryonic cartilage tissue. Addition of cAMP phosphodiesterase inhibitors together with cAMP to the incubation media prevents the stimulation of macromolecular biosynthesis observed under the influence of cAMP. Studies on cAMP metabolism revealed that this compound is rapidly catabolized to AMP and adenosine. The latter enters the cells and incorporates into the adenyl nucleotide intracellular pool. The stimulant action of exogenous cAMP is related to its extracellular metabolism rather than to the intracellular effects of the nucleotide.