Pituitary cells

During the isolation of inhibin from foUicular fluid, some chromatographic fractions stimulated FSH release from cultured anterior pituitary cells, suggesting the existence of FSH releasing proteins (FRPs). Two FRPs, given the generic term activins, were subsequentiy isolated (131,132). One is composed of two disulfide-finked P-A subunits (activin A) the other consists of similarly finked P-A and P-B subunits (activin AB). 

Cl -channels are also present in neuroendocrine cells such as the AtT-20 pituitary cell line [30]. Ca -dependent and voltage-activated slow Cl -currents were found. These Cl -currents could subserve a role comparable to that of Cl -currents in renin-secreting cells or mast cells [13,14]. Along these lines, it has been speculated that the slow Cl inward currents may influence the firing rate of these neuroendocrine cells [30]. 

In conclusion, ET is a polyfunctional cytokine that affects monocytes as well as vascular smooth muscle cells, anterior pituitary cells, and renal mesangial cells. In the biologic interface between ischemic or injured endothelium and monocytes, neutrophils, or lymphocytes, ET may play a significant role. 

Li, S., Crenshaw, E. B., Rawson, E. J., Simmons, D. M., Swanson, L. W and Rosenfeld, M. G. (1990). Dwarf locus mutants lacking three pituitary cell types result from mutations in the POU-domain gene pit-1. Nature 347 528-533. 

Second, dopamine has been linked covalently to a poly(aryloxy-phosphazene) via a diazo-coupling technique (24). Experiments showed that rat pituitary cells in culture responded to the surface-bound dopamine in a similar manner to that found when the dopamine was free in solution. 

Martin, T. F. J. and Walent, J. H. A new method for cell per-meabilization reveals a cytosolic protein requirement for Ca2+-activated secretion in GH3 pituitary cells. /. Biol. Chem. 264 10299-10308,1989. 

Sartor P, Vacher P, Mollard P, Dufy B (1988) Tamoxifen reduces calcium currents in a clonal pituitary cell line. Endocrinology 123 534-540... 

In rats and mice both ER transcripts and proteins have been identified in 60-70% of anterior pituitary cells (Kuiper et al. 1997 Wilson et al. 1998 Wilson et al. 1998 Nishihara et al. 2000 Pelletier et al. 2000). While ERa is the predominant subtype in adult rats, in anterior pituitaries from fetal and prepubertal animals ER/i appears to be expressed in greater abundance (Nishihara et al. 2000). In addition, differential developmental and estrogen-dependent expression of pituitary ERs has been reported (Pasqualini et al. 1999). Approximately... 

DemayF, De Monti M, Tiffoche C, Vaillant C, Thieulant ML (2001) Steroid-independent activation of ER by GnRH in gonadotrope pituitary cells. Endocrinology 142 3340-3347... 

Drouin J, Labrie F (1981) Interactions between 17 beta-estradiol and progesterone in the control of luteinizing hormone and follicle-stimulating hormone release in rat anterior pituitary cells in culture. Endocrinology 108 52-57... 

Schreihofer DA, Staler MH, Shupnik MA (2000) Differential expression and regulation of estrogen receptors (ERs) in rat pituitary cell lines estrogen decreases ERa protein and estrogen responsiveness. Endocrinology 141 2174-2184... 

Malarkey, W.B. and Zvara, B.J., Interleukin-1-6 and other cytokines stimulate ACTH release from cultured pituitary cells of patients with Cushing s Disease, J. Clin. Endocrinol. Metab., 69, 196, 1989. 

S.A. Andric, T.S. Kostic, and S.S. Stojilkovic. Contribution of Multidrug Resistance Protein MRP5 in Control of Cyclic Guanosine 5 -Monophosphate Intracellular Signaling in Anterior Pituitary Cells. Endocrinology. 147 3435-3445 (2006). 

Varney MA, Godfrey PP, Drummond AH, et al Chronic lithium treatment inhibits basal and agonist-stimulated responses in rat cerebral cortex and GHj pituitary cells. Mol Pharmacol 4 671-678, 1992... 

Wynick, D. and Bloom, S. R (1990) Magnetic bead separation of anterior pituitary cells. Neuroendocrinology 52, 560-565. 

Control of hormone synthesis and secretion in the anterior pituitary. Neurosecretory neurons in the hypothalamus liberate polypeptides that either stimulate or inhibit hormone synthesis by specialized pituitary cells containing the appropriate receptors. For example, GnRH stimulates gonadotroph cells in the pituitary to synthesize and secrete LH and FSH. These pituitary hormones then impinge on target cells, typically stimulating them to make other low-molecular-weight hormones. The end products of these cascades feedback-inhibit hormone production at either or both hypothalamic and pituitary levels. 

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