title: Phorbol esters have a dual action through protein kinase C in regulation of proliferation of FRTL-5 cells.
abstract: In quiescent rat thyroid (FRTL-5) cells, phorbol-12-myristate-13-acetate (PMA) inhibited DNA synthesis induced by a combination of insulin and thyrotropin (TSH) or dibutyryl cyclic AMP (Bt2cAMP). This inhibitory effect of PMA was observed even when PMA was added after addition of these growth factors, and was maximal when PMA was added 2-4 h after the growth factors (late in the G1-phase of the cell cycle). On the other hand, PMA alone induced DNA synthesis and also enhanced that induced by Bt2cAMP or insulin in these quiescent cells. 1-Oleoyl-2-acetylglycerol mimicked these effects of PMA, but 4 alpha-phorbol-12,13-didecanoate had no effect. These data demonstrate that in FRTL-5 cells protein kinase C has a stimulatory effect on the G0 to G1 transition and an inhibitory effect on the G1 to S transition in the cell cycle.
authors.affiliation: Department of Laboratory Medicine, Osaka University Medical School, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Takada
authors.forename: N
authors.initials: N
authors.lastname: Amino
authors.forename: T
authors.initials: T
authors.lastname: Tetsumoto
authors.forename: K
authors.initials: K
authors.lastname: Miyai
mesh_terms: D000818:Animals; D003994:Bucladesine / Q000494:pharmacology; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D004247:DNA / Q000096:biosynthesis; D004075:Diglycerides / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects; D007328:Insulin / Q000494:pharmacology; D007700:Kinetics; D010703:Phorbol Esters / Q000494:pharmacology*; D011493:Protein Kinase C / Q000378:metabolism*; D051381:Rats; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D013961:Thyroid Gland / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D013972:Thyrotropin / Q000494:pharmacology
chemical_list: D004075:Diglycerides; D007328:Insulin; D010703:Phorbol Esters; D003994:Bucladesine; C038237:1-oleoyl-2-acetylglycerol; D013972:Thyrotropin; D004247:DNA; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate