epidermal-growth-factor and 3-4-3--4--tetrachlorobiphenyl
epidermal-growth-factor has been researched along with 3-4-3--4--tetrachlorobiphenyl* in 2 studies
Other Studies
2 other study(ies) available for epidermal-growth-factor and 3-4-3--4--tetrachlorobiphenyl
Article | Year |
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Zinc increases EGF-stimulated DNA synthesis in primary mouse hepatocytes. Studies in tumor promoter-treated cell cultures.
To investigate factors influencing cell proliferation, cells are often cultured in serum-free medium. In the present study it is shown that addition of zinc chloride (40 microM) to primary mouse hepatocytes, cultured in Dulbecco's minimal essential medium, markedly enhanced growth factor (EGF)-stimulated [3H]thymidine incorporation into DNA. Treatment of cell cultures with phenobarbital or 3,4,3',4'-tetrachlorobiphenyl (enzyme inducers and tumor promoters in vivo) or with 12-O-tetradecanoylphorbol-13-acetate (the classical skin tumor promoter) further increased EGF-stimulated DNA synthesis. The results emphasize the need to adequately substitute zinc in serum-free cultured cells. Topics: Animals; Carcinogens; Cell Division; Cells, Cultured; Chlorides; Culture Media; DNA; Drug Interactions; Epidermal Growth Factor; Kinetics; L-Lactate Dehydrogenase; Liver; Male; Mice; Mice, Inbred C57BL; Phenobarbital; Polychlorinated Biphenyls; Tetradecanoylphorbol Acetate; Zinc; Zinc Compounds | 1990 |
Altered growth control of rat hepatocytes after treatment with 3,4,3',4'-tetrachlorobiphenyl in vivo and in vitro.
Alterations of hepatocyte growth control by inducers of drug-metabolizing enzymes were investigated using 3,4,3',4'-tetrachlorobiphenyl (TCB) as the inducing agent. TCB was chosen as a selective 3-methylcholanthrene-type inducer and liver tumor promoter which probably exerts its biological actions through binding to the aryl hydrocarbon (Ah) receptor. In vivo treatment of rats with TCB (200 mg/kg) markedly stimulated growth of enzyme altered liver foci and [3H]-thymidine incorporation into nuclear DNA. Hepatocyte cultures from TCB-treated rats were more sensitive to exogenous growth factors such as EGF than those from untreated controls. In vitro TCB exposure of hepatocyte cultures also altered hepatocyte growth control in a dose-dependent manner and induced drug-metabolizing enzymes. TCB treatment in vivo enhanced EGF-stimulated autophosphorylation of the EGF receptor in liver plasma membranes. The results suggest that altered growth control is due to a direct effect of TCB on hepatocytes. The proposed model may be useful to elucidate a possible linkage between the functional stress imposed on hepatocytes by sustained overexpression of an adaptive program and modulation of hepatocyte growth control. Topics: 7-Alkoxycoumarin O-Dealkylase; Animals; Carcinogens; Cell Division; Cells, Cultured; DNA Replication; Epidermal Growth Factor; Glucuronosyltransferase; Liver; Male; Oxygenases; Phosphorylation; Polychlorinated Biphenyls; Rats; Rats, Inbred Strains | 1988 |