Hypophysiotropic and neuromodulatory regulation of adrenocorticotropin in the human fetal pituitary gland.

AUTOR(ES)

Blumenfeld, Z

RESUMO

Synthetic human corticotropin-releasing factor (hCRF) stimulated ACTH secretion by human fetal pituitaries in superfusion and dispersed human fetal pituitary cells cultured on an extracellular matrix in static incubation from 14 to 23 wk gestational age. The action of hCRF in vitro was potentiated by arginine vasopressin (AVP) at all ages studied. 8-Br-cAMP induced a response similar to hCRF. The AVP effect on ACTH was synergistic with both CRF and 8-Br-cAMP. hCRF-mediated secretion of ACTH was noncompetitively inhibited by 24-h pretreatment, or by 3-h concomitant treatment, with dexamethasone. Neither oxytocin, catecholamines, prostaglandins, nor indomethacin exerted significant effects on ACTH secretion, either alone or in combination with hCRF or AVP during the gestational ages studied. These results support a physiologic role for CRF in the regulation of secretion by corticotropic cells as early as 14 wk gestation, by which time corticotropes and ability to secrete ACTH have been demonstrated.

Documentos Relacionados

• Immunolocalisation of cytokeratins in the normal and neoplastic human pituitary gland.
• Activin and inhibin in the human adrenal gland. Regulation and differential effects in fetal and adult cells.
• Development of peptide-containing nerves in the human fetal prostate gland.
• Immunocytochemistry of folliculo-stellate cells of normal and neoplastic human pituitary gland.
• GATA-binding proteins regulate the human gonadotropin alpha-subunit gene in the placenta and pituitary gland.