title: Effect of dibutyryl cAMP on cell cycle progression of rat brain tumor cells in vitro.
abstract: Autoradiographic and flow microfluorometry analyses have been applied to a study of perturbed cell kinetics in 9L rat brain tumor cells treated with dibutyryl cyclic AMP and theophylline alone and in combination in vitro. At a concentration of 1 mM each, cell growth ceased shortly after the administration of these drugs. The results indicate that cells in S and G2 phase at the time of drug administration can undergo mitosis even though a considerable prolongation of G2 phase was apparent. However, cells in G1 at the time of drug administration was arrested in that phase, whereas those cells in S or G2 were able to complete one mitosis before becoming arrested in the G1 phase. This blocking effect was reversible, and cells resumed proliferation at a normal rate shortly after the removal of these drugs.
mesh_terms: D000818:Animals; D001345:Autoradiography; D001932:Brain Neoplasms / Q000473:pathology*; D003994:Bucladesine / Q000494:pharmacology*; D002453:Cell Cycle / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured / Q000187:drug effects / Q000378:metabolism; D000242:Cyclic AMP / Q000494:pharmacology; D005470:Fluorometry; D066298:In Vitro Techniques; D007399:Interphase / Q000187:drug effects; D051381:Rats; D013806:Theophylline / Q000494:pharmacology
chemical_list: D003994:Bucladesine; D013806:Theophylline; D000242:Cyclic AMP