title: Cadmium-induced alterations in RNA metabolism in cultures of Chinese hamster cells sensitive to and resistant to the cytotoxic effects of cadmium.
abstract: A variant population (CdR) of cultured Chinese hamster cells (line CHO) was derived that is more than 100 times as resistant to the cytotoxic effects of Cd2+ than is the parent population. The effects on RNA metabolism of exposure to sublethal concentrations of Cd2+ were studied in CHO and CdR. Exposure to 2 X 10(-7) M CdCl2 for 24 h resulted in increased polysome content (1.2 times) and increased uridine or adenosine incorporation into heterogeneous nuclear RNA (1.2-1.4 times) and messenger RNA ((1.5-1.7 times) in both populations. Measurement of ATP pool specific activity following exposure to radiolabeled adenosine showed that increased incorporation reflects increased synthesis. The equivalence of CHO and CdR in dose-response in terms of stimulated RNA synthesis and their disparity in dose-response in terms of cytotoxic effects indicate that the systems involved in conferring protection against the lethal effects of Cd2+ are not similarly involved in attenuating the effects on RNA metabolism.
mesh_terms: D000241:Adenosine / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D002104:Cadmium / Q000494:pharmacology*; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D006224:Cricetinae; D003412:Cricetulus; D003593:Cytoplasm / Q000378:metabolism; D004351:Drug Resistance; D012313:RNA / Q000378:metabolism*; D013997:Time Factors; D014529:Uridine / Q000378:metabolism
chemical_list: D002104:Cadmium; D012313:RNA; D000255:Adenosine Triphosphate; D000241:Adenosine; D014529:Uridine