Effect of cAMP on macromolecule synthesis in the pathogenic protozoa Trypanosoma cruzi.
Macromolecule synthesis of Trypanosoma cruzi in culture was monitored using radioactive tracers. Cells of different days in culture displayed a preferential incorporation of precursors as follows: 1 day for (3H)-thymidine cells; 3 days for (3H)-uridine cells, and 4 days for (3H)-leucine cells. Autoradiographic studies showed that (3H)-thymidine was incorporated in the DNA of both kinetoplast and nucleus in this order. Shifts in the intracellular content of cAMP either by addition of dibutyryl-cAMP or by stimulation of the adenylcyclase by isoproterenol, caused an inhibition in the synthesis of DNA, RNA and proteins. Addition to the T. cruzi cultures of these agents which elevate the intracellular content of cAMP provoked an interruption of cell proliferation as a result of the impairment of macromolecule synthesis. A discrimination was observed among the stereoisomers of isoproterenol, the L configuration showing to be the most active.
Santos
D O
DO
Instituto Oswaldo Cruz, Departamento de Protozoologia, Rio de Janeiro, Brasil.
Oliveira
M M
MM
D000818:Animals; D001345:Autoradiography; D001665:Binding Sites; D002455:Cell Division / Q000187:drug effects; D003470:Culture Media; D000242:Cyclic AMP / Q000378:metabolism*; D011849:Radioactive Tracers; D014349:Trypanosoma cruzi / Q000254:growth & development*
D003470:Culture Media; D011849:Radioactive Tracers; D000242:Cyclic AMP