Effects of synthetic gonadotropin-releasing hormone on incorporation of radioactive glucosamine and amino acids into luteinizing hormone and total protein by rat pituitaries in vitro.

  title={Effects of synthetic gonadotropin-releasing hormone on incorporation of radioactive glucosamine and amino acids into luteinizing hormone and total protein by rat pituitaries in vitro.},
  author={T C Liu and Gary L. Jackson and Jack Gorski},
  volume={98 1},
The influence of synthetic gonadotropin-releasing hormone (GnRH) on incorporation of glucosamine and amino acids into LH and total protein was investigated. Rat pituitaries were incubated in vitro with radioactive precursors for 4 h at 37 C. Labeled LH was isolated by immunoprecipitation with specific anti-LH-beta serum. Total LH in the medium and pituitary glands was measured by radioimmunoassay. GnRH significantly stimulated incorporation of [3H]glucosamine into LH in pituitaries from… Expand
Comparison of the biosynthesis and release of luteinizing hormone by rat pituitaries in vitro in response to gonadotropin-releasing hormone analogs.
In an attempt to determine whether gonadotropin-releasing hormone (GnRH) regulates synthesis and release of LH via independent processes, the ability of several GnRH analogs to regulate LH releaseExpand
Biosynthesis of gonadotropins by rat pituitary cells in culture and in pituitary homogenates: Effect of gonadotropin-releasing hormone
The incorporation of labeled amino acids and glucosamine into LH and FSH by cultured rat anterior pituitary cells and anterior pituitary homogenates is reported. There was a significant augmentationExpand
The effects of gonadotropin-releasing hormone and estradiol on luteinizing hormone biosynthesis in cultured rat anterior pituitary cells.
GnRH regulates both LH glycosylation and LH polypeptide synthesis and that E2 lowers the physiological concentration of GnRH necessary to stimulate this biosynthetic response, and estrogen's enhancement of Gn RH-stimulated LH release appears to be due to its action on mechanisms regulating the release of previously synthesized stored hormone. Expand
Basal and gonadotrophin-releasing hormone-induced biosynthesis and release of luteinizing hormone: Effect of calcium deprivation
  • M. Apfelbaum
  • Medicine, Biology
  • Molecular and Cellular Endocrinology
  • 1992
GnRH-stimulated LH glycosylation and LH translation involve calcium-dependent mechanisms, and the results suggest that the release of newly synthesized LH is regulated differently from previously synthesized stored hormone. Expand
LH biosynthesis and secretion in rat anterior pituitary cell cultures: stimulation of LH glycosylation and secretion by GNRH and an agonistic analogue and blockade by an antagonistic analogue.
The results suggest that GnRH and agonistic analogues may preferentially regulate turnover or synthesis of the carbohydrate moiety of LH. Expand
Modifications of luteinizing hormone biosynthesis and release by gonadotropin-releasing hormone, cycloheximide, and actinomycin D.
The data suggest that the time course for the release of preexisting IR-LH differs from that for newly synthesised LH, and the newly synthesized LH released in response to high levels of GnRH has more sugar residues than that released under basal conditions. Expand
Synthesis and release of luteinizing hormone in vitro by rat anterior pituitary cells: effects of gallopamil hydrochloride (D600) and pimozide.
The results demonstrate that D600 and pimozide inhibit both GnRH-induced LH glycosylation and release, which are both mediated by similar Ca2+-dependent pathways. Expand
Characterization of luteinizing hormone synthesized and released by rat pituitaries in vitro: dissociation of immunological and biological activities.
The LH synthesized de novo by rat anterior pituitary glands in vitro by monitoring the radioactivity of LH immunoprecipitated with anti-LH-β serum was characterized and newly synthesized radiolabeled LH was measured. Expand
Gonadotropin-releasing hormone increases the amount of messenger ribonucleic acid for gonadotropins in ovariectomized ewes after hypothalamic-pituitary disconnection.
It was considered that the pituitary gland remained viable and functioned independently of hypothalamic input in OVX ewes after HPD and there were no differences in the amount of mRNA for GH or PRL or the pituitsary content of these hormones among treatments. Expand
Biosynthesis, Glycosylation, and Secretion of Rat Luteinizing Hormone α- and β-Subunits: Differential Effects of Orchiectomy and Gonadotropin-Releasing Hormone*
Neither orchiectomy nor GnRH had any effect on [35S]Cys or [3H]GlcN incorporation into intracellular or secreted total protei... Expand