Forskolin and 12-0-tetradecanoylphorbol-13-acetate mimic thyrotropin-stimulated protein iodination in mouse thyroid.
In the present study, the capacity of the diterpene, forskolin, and the phorbol ester, 12-0-tetradecanoylphorbol-13-acetate (TPA), to stimulate protein iodination in freshly dispersed mouse thyroid open follicles was assessed. Although both agents stimulated 125I incorporation into TCA precipitable material, dose response curves (0.1 - 25 microM) showed that maximal concentrations of either agonist alone failed to reproduce the stimulatory effect of a maximal concentration of thyrotropin (TSH; 50 mU/ml). When a maximal concentration of forskolin (20 microM) and TPA (10 microM) were added in combination, the stimulatory effect was additive and mimicked the effect of TSH. TPA had no significant effect on either basal or forskolin-stimulated cyclic-AMP production. We conclude that the regulation of protein iodination by TSH may involve both the adenylate cyclase-cyclic-AMP-dependent protein kinase system and the diacylglycerol-activated calcium/phospholipid-dependent protein kinase C pathway.
Levasseur
S
S
Morgan
L
L
Friedman
Y
Y
Burke
G
G
D000262:Adenylyl Cyclases / Q000378:metabolism; D000818:Animals; D005576:Colforsin; D004224:Diterpenes / Q000494:pharmacology*; D005260:Female; D007455:Iodine / Q000378:metabolism*; D051379:Mice; D010704:Phorbols / Q000494:pharmacology*; D011493:Protein Kinase C; D011494:Protein Kinases / Q000378:metabolism; D011506:Proteins / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*; D013961:Thyroid Gland / Q000187:drug effects / Q000378:metabolism*; D013972:Thyrotropin / Q000494:pharmacology*
D004224:Diterpenes; D010704:Phorbols; D011506:Proteins; D005576:Colforsin; D013972:Thyrotropin; D007455:Iodine; D011494:Protein Kinases; D011493:Protein Kinase C; D000262:Adenylyl Cyclases; D013755:Tetradecanoylphorbol Acetate