Pituitary corticotroph SOCS-3: novel intracellular regulation of leukemia-inhibitory factor-mediated proopiomelanocortin gene expression and adrenocorticotropin secretion.

As pituitary leukemia-inhibitory factor (LIF) mediates neuroimmune signals to the hypothalamo-pituitary-adrenal axis, we tested the role of intracellular SOCS-3 in corticotroph function. SOCS-3, a cytokine-inducible protein of the suppressor of cytokine signaling (SOCS) family, is expressed in the murine pituitary in vivo. After i.

Leukemia inhibitory factor regulates proopiomelanocortin transcription.

Leukemia inhibitory factor (LIF), a pleiotropic cytokine, is expressed in both fetal and adult pituitary tissue, and LIF immunoreactivity is found in functional human pituitary tumors. LIF induces basal, and augments CRH-induced, POMC mRNA and ACTH secretion from AtT20 cells. Therefore, we examined LIF signaling and LIF regulation of POMC expression in AtT20 cells.

Leukemia inhibitory factor (LIF) induces acute adrenocorticotrophic hormone (ACTH) secretion in fetal rhesus macaque primates: a novel dynamic test of pituitary function.

Leukemia Inhibitory Factor (LIF), a pituitary cytokine, and LIF receptors are expressed in human fetal and adult adenohypophyseal cells. LIF induces adrenocorticotropin hormone (ACTH) secretion in vitro and potently synergizes with both corticotropin-releasing hormone (CRH) and cAMP-induced pro-opiomelanocortin (POMC) transcription. We therefore investigated the effects of intra-carotid administration of recombinant human LIF to chronically catheterized fetal non-human primates.

Unwanted effects of growth hormone excess in the adult.

This review discusses in vitro, animal and human studies which provide insights into the deleterious effects of excess GH and IGF-I. The systemic sequelae of hypersomatotrophism include disorders of the cardiovascular, respiratory and rheumatologic systems. Impaired carbohydrate metabolism and an increased incidence of gastrointestinal malignancy also contribute to morbidity and an average 10 year reduction in mortality.

IGF-I receptor signalling: lessons from the somatotroph.

Insulin-like growth factor 1 (IGF-I) is a major feedback regulator of pituitary GH secretion, with defined actions occurring at both the hypothalamus and pituitary. The IGF-I gene is expressed in the anterior pituitary in a GH-dependent manner thus providing for both endocrine-as well as autocrine-mediated GH regulation. In turn, IGF-I selectively and specifically inhibits GH gene transcription and secretion, its attenuating effects on nascent GH mRNA synthesis being demonstrable within 1 h.