Cortisol rapidly reduces prolactin release and cAMP and 45Ca2+ accumulation in the cichlid fish pituitary in vitro
| Autor: | Lisa M.H. Helms, N.H. Richman, Russell J. Borski, E.G. Grau |
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| Rok vydání: | 1991 |
| Předmět: |
Agonist
endocrine system medicine.medical_specialty Pituitary gland Multidisciplinary medicine.drug_class Biology Peptide hormone Prolactin medicine.anatomical_structure Endocrinology Internal medicine medicine hormones hormone substitutes and hormone antagonists Intracellular Glucocorticoid Research Article Hydrocortisone medicine.drug Endocrine gland |
| Zdroj: | Proceedings of the National Academy of Sciences. 88:2758-2762 |
| ISSN: | 1091-6490 0027-8424 |
| Popis: | During in vitro incubation, prolactin release is inhibited in a dose-related manner by cortisol. This action is mimicked by the synthetic glucocorticoid agonist dexamethasone but not by other steroids tested. Perifusion studies indicate that the inhibition of [3H]prolactin release by cortisol occurs within 20 min. Cortisol (50 nM) also inhibits cAMP accumulation and reduces 45Ca2+ accumulation in the tilapia rostral pars distalis within 15 min. Cortisol's action on prolactin release is blocked in the presence of either the Ca2+ ionophore A23187 or a combination of dibutyryl cAMP and 3-isobutyl-1-methylxanthine, which increase intracellular Ca2+ and cAMP, respectively. Taken together, these findings suggest that cortisol may play a physiologically relevant role in the rapid modulation of prolactin secretion in vivo. Our studies also suggest that the inhibition of prolactin release by cortisol is a specific glucocorticoid action that may be mediated, in part, through cortisol's ability to inhibit intracellular cAMP and Ca2+ metabolism. |
| Databáze: | OpenAIRE |
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