Induction of type II 5'-deiodinase activity in cultured rat astroglial cells by 12-O-tetradecanoylphorbol-13-acetate: dependence on glucocorticoids.
The effect of an activator of protein kinase C, 12-O-tetradecanoylphorbol-13-acetate (TPA), on the 5'-deiodinase (5'D) activity was studied in rat astroglial cells cultured in chemically defined medium. TPA promoted a large increase in the type II 5'D activity, which was maximal 5-10 h after addition of TPA and then declined to the basal level at 24 h. The optimal TPA concentration was 10(-7) M. TPA and 8-Br-cAMP, an other inducer of 5'D activity were antagonist. Otherwise, TPA stimulated 5'D activity only in the presence of glucocorticoids at concentrations from 10(-8) M to 10(-4) M. Glucocorticoids alone induced a slight increase in 5'D activity. These data indicate that protein kinase C contributes to the control of 5'D activity in astroglial cells and that its action is dependent on glucocorticoids.
Courtin
F
F
Unité de Recherche sur la Glande Thyroïde et la Régulation Hormonale (U.96) de l'Institut National de la Santé et de la Recherche Médicale, Le Kremlin-Bicêtre, France.
Chantoux
F
F
Gavaret
J M
JM
Toru-Delbauffe
D
D
Jacquemin
C
C
Pierre
M
M
D015124:8-Bromo Cyclic Adenosine Monophosphate / Q000494:pharmacology; D000818:Animals; D000831:Animals, Newborn; D001253:Astrocytes / Q000187:drug effects / Q000201:enzymology*; D001921:Brain / Q000201:enzymology; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000378:metabolism; D003907:Dexamethasone / Q000494:pharmacology; D004790:Enzyme Induction; D006854:Hydrocortisone / Q000494:pharmacology; D007453:Iodide Peroxidase / Q000096:biosynthesis*; D007527:Isoenzymes / Q000096:biosynthesis*; D007700:Kinetics; D051381:Rats; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
D007527:Isoenzymes; D015124:8-Bromo Cyclic Adenosine Monophosphate; D003907:Dexamethasone; D000242:Cyclic AMP; D007453:Iodide Peroxidase; D013755:Tetradecanoylphorbol Acetate; D006854:Hydrocortisone