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Androgens decrease LHRH binding sites in rat anterior pituitary cells in culture.

V Giguere·F A Lefebvre·F Labrie
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Abstract

[125I]-[D-Ser(TBU)6]LHRH-EA binds to a single class of high affinity sites in rat anterior pituitary cells in culture at an apparent dissociation constant of 0.25 nM at 0-4C. The order of potency of a representative group of LHRH agonists and antagonists to displace the labeled ligand is similar to their LH-releasing activity. Treatment of pituitary cells for 48 h with 100 nM 5 alpha-dihydrotestosterone leads to a 40% decrease of the number of LHRH receptors with no change of binding affinity. This loss of LHRH receptors is accompanied by a similar decrease of the LH responsiveness to LHRH, thus providing the first evidence for a direct effect of sex steroids on pituitary LHRH receptors as a possible mechanism of feedback action.

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AndrogensAnimalsBinding SitesBinding, CompetitiveCells, CulturedDihydrotestosteroneFemaleGonadotropin-Releasing HormoneKineticsPituitary Gland, AnteriorRatsReceptors, Cell SurfaceReceptors, LHRHJournal Article

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V Giguere, F A Lefebvre, F Labrie. 1981. Androgens decrease LHRH binding sites in rat anterior pituitary cells in culture.. https://doi.org/10.1210/endo-108-1-350

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Androgens↗
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