title: [Determination of substances inhibiting and stimulating the binding of FSH to its receptors].
abstract: We describe a method to estimate binding of human 125I-FSH to a preparation of bovine testicular receptors. Various experimental conditions are tested and the validity of the method is demonstrated. Using this method, the presence of biological substances modifying the FSH binding is measured in various fractions of ram retetestis fluid submitted to several steps of purification by chromatography. FSH receptor binding inhibitor (FSHRBI) activity is obtained in a low molecular weight fraction and FSH receptor binding stimulator activity in a larger one. These cybernin activities are isolated in fractions different from the ones observed with inhibin and GnRH like activities.
mesh_terms: D000818:Animals; D001826:Body Fluids / Q000032:analysis; D002417:Cattle; D005640:Follicle Stimulating Hormone / Q000037:antagonists & inhibitors* / Q000302:isolation & purification / Q000378:metabolism*; D006727:Hormone Antagonists / Q000302:isolation & purification*; D007265:Inhibins; D007457:Iodine Radioisotopes; D008297:Male; D008722:Methods; D011956:Receptors, Cell Surface / Q000378:metabolism*; D011962:Receptors, FSH; D012152:Rete Testis / Q000032:analysis / Q000502:physiology; D012756:Sheep; D013737:Testis / Q000378:metabolism*
chemical_list: D006727:Hormone Antagonists; D007457:Iodine Radioisotopes; D011956:Receptors, Cell Surface; D011962:Receptors, FSH; D007265:Inhibins; D005640:Follicle Stimulating Hormone
vernacular_title: Dosage des substances inhibant et stimulant la fixation de la FSH à ses récepteurs.