Differential control of type-I iodothyronine deiodinase expression by the activation of the cyclic AMP and phosphoinositol signalling pathways in cultured human thyrocytes
| Autor: | G J Beckett, John R. Arthur, S W Walker, Lee David C, S G Beech |
|---|---|
| Rok vydání: | 1995 |
| Předmět: |
medicine.medical_specialty
Cell Ionophore Thyroid Gland chemistry.chemical_element 8-Bromo Cyclic Adenosine Monophosphate Thyrotropin Stimulation Calcium Phosphatidylinositols Iodide Peroxidase chemistry.chemical_compound Endocrinology Sodium Selenite Internal medicine medicine Cyclic AMP Humans Dimethyl Sulfoxide Thyroid Neoplasms Thyroid Nodule Selenoproteins Molecular Biology Calcimycin Cells Cultured Carcinoma Proteins Graves Disease medicine.anatomical_structure chemistry Iodothyronine deiodinase Enzyme Induction Phorbol Microsome Microsomes Liver Tetradecanoylphorbol Acetate Signalling pathways Signal Transduction |
| Zdroj: | Journal of molecular endocrinology. 14(2) |
| ISSN: | 0952-5041 |
| Popis: | The effects of TSH and the activation of the cyclic AMP (cAMP) and Ca2+-phosphatidylinositol (Ca2+-PI) cascades on the activity and expression of the selenoenzyme thyroidal type-I iodothyronine deiodinase (ID-I) have been studied using human thyrocytes grown in primary culture. Stimulation of ID-I activity and expression was obtained with TSH and an analogue of cAMP, 8-bromo-cAMP. In the presence or absence of TSH, the addition of the phorbol ester, phorbol 12-myristate 13-acetate (PMA) together with the calcium ionophore A23187, caused a decrease in ID-I activity; a decrease in ID-I expression was also observed as assessed by cell labelling with [75 Se]selenite. PMA alone had no effect on ID-I activity in the presence or absence of TSH. A23187 alone produced a small but significant reduction in ID-I activity, but only in TSH-stimulated cells. These data provide evidence that the expression of thyroidal ID-I is negatively regulated by the Ca2+-PI cascade, and positively regulated by the cAMP cascade. |
| Databáze: | OpenAIRE |
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