Effects of activin A on deoxyribonucleic acid synthesis, iodine metabolism, and cyclic adenosine monophosphate accumulation in porcine thyroid cells.
We have recently shown the presence of activin A in human thyroid cells. To determine whether activin A affects the growth and function of the thyroid, we investigated its effects on DNA synthesis, iodine metabolism, and cAMP accumulation in cultured porcine thyroid cells. Activin A increased DNA synthesis. This effect was abolished by addition of follistatin but additively enhanced by epidermal growth factor. In contrast, activin A significantly reduced uptake and release of iodide by the thyroid and also TSH-induced cAMP accumulation but did not inhibit the cAMP accumulation induced by forskolin. These data indicate that activin A stimulates thyroid growth irrespective of cAMP accumulation and inhibits thyroid function.
Kotajima
A
A
First Department of Internal Medicine, School of Medicine, University of Tokushima, Japan.
Miyamoto
Y
Y
Tsuruo
M
M
Kosaka
M
M
Saito
S
S
D028341:Activins; D000818:Animals; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000378:metabolism*; D004247:DNA / Q000096:biosynthesis*; D004305:Dose-Response Relationship, Drug; D004815:Epidermal Growth Factor / Q000494:pharmacology; D006133:Growth Substances / Q000494:pharmacology; D007265:Inhibins / Q000494:pharmacology*; D007455:Iodine / Q000378:metabolism*; D013552:Swine; D013936:Thymidine / Q000378:metabolism; D013961:Thyroid Gland / Q000166:cytology / Q000378:metabolism*
D006133:Growth Substances; D028341:Activins; D007265:Inhibins; D004815:Epidermal Growth Factor; D004247:DNA; D007455:Iodine; D000242:Cyclic AMP; D013936:Thymidine