Extracellular signal-regulated kinases (ERK1/2) signaling pathway plays a role in cortisol secretion in the long-term hypoxic ovine fetal adrenal near term
| Autor: | Charles A. Ducsay, Kanchan M. Kaushal, Dean A. Myers, Vladimir E. Vargas, Tshepo R. Monau |
|---|---|
| Rok vydání: | 2013 |
| Předmět: |
Cortisol secretion
MAPK/ERK pathway endocrine system medicine.medical_specialty Hydrocortisone MAP Kinase Signaling System Physiology Blotting Western 8-Bromo Cyclic Adenosine Monophosphate Stimulation Adrenocorticotropic hormone Biology Fetal Hypoxia Adrenocorticotropic Hormone Pregnancy Physiology (medical) Internal medicine Adrenal Glands Nitriles Butadienes medicine Extracellular Animals Enzyme Inhibitors Phosphorylation Mitogen-Activated Protein Kinase 1 Mitogen-Activated Protein Kinase 3 Sheep Hormones Reproduction and Development Kinase Adrenal cortex medicine.anatomical_structure Endocrinology Adrenal Cortex Female hormones hormone substitutes and hormone antagonists medicine.drug |
| Zdroj: | American Journal of Physiology-Regulatory, Integrative and Comparative Physiology. 304:R636-R643 |
| ISSN: | 1522-1490 0363-6119 |
| DOI: | 10.1152/ajpregu.00318.2012 |
| Popis: | This study assessed the role of the extracellular signal-regulated kinase (ERK) signaling pathway on the previously observed enhanced cortisol secretion in response to adrenocorticotropic hormone (ACTH) treatment in fetal adrenocortical cells (FACs) from long-term hypoxic (LTH) ovine fetuses. Ewes were maintained at high altitude (3,820 m) from ∼40 to 138–141 days gestation when FACs were collected and challenged with either ACTH (10 nM) or 8-bromoadenosine 3′,5′-cyclic monophosphate (8-bromo-cAMP, 10 mM) in the presence or absence of the mitogen-activated protein kinase/extracellular signal-regulated protein kinase (MEK)/ERK inhibitor UO126 (10 μM). FACs from age-matched normoxic fetuses served as controls. Media and FACs were collected at selected time intervals after ACTH or 8-bromo-cAMP stimulation for cortisol measurement and Western analysis of ERK1/2 and phospho-ERK1 and -2 (pERK1/2). After ACTH or 8-bromo-cAMP treatment, cortisol production was greater in the LTH group compared with control ( P < 0.05). UO126 reduced ACTH and 8-bromo-cAMP-mediated cortisol output in both groups ( P < 0.01 vs. ACTH or 8-bromo-cAMP alone). Under basal conditions, ERK1/2 and pERK1/2 were not different between LTH and normoxic fetuses. In response to ACTH or 8-bromo-cAMP treatment, ERK1/2 were not different between groups; however, pERK1/2 were elevated in the LTH FACs compared with normoxic control FACs. ERK1/2 phosphorylation declined following ACTH treatment in the control group, but UO126 had no effect on ERK1/2 compared with untreated levels. Both ACTH and 8-bromo-cAMP treatment resulted in a decline of protein levels. UO126 pretreatment virtually eliminated pERK1/2 expression. We conclude that basal ERK signaling in FACs is necessary for normal cortisol production and sustained pERK in LTH adrenals enhances cortisol production. |
| Databáze: | OpenAIRE |
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