title: Stimulatory effect of a GnRH agonist (buserelin) in in vitro and in vivo testosterone production by the frog (Rana esculenta) testis.
abstract: The summary testicular effects of an agonistic analogue of gonadotropin-releasing hormone (buserelin, GnRHa) have been studied in vitro and in vivo in the frog, Rana esculenta. During 3 h incubation GnRHa (8 X 10(-7) M) potentiated pituitary factors in stimulating testosterone production by minced testes in vitro. After 6 h of incubation 8 X 10(-7) M GnRHa stimulated maximal testosterone output. Testes of 10-day hypophysectomized animals did not show any GnRHa effect in vitro. In vivo, a direct effect of GnRHa on testicular testosterone production was demonstrated in hypophysectomized animals, although this effect was temperature-dependent, requiring the frog to be maintained at a high temperature (24 degrees C). No effect of GnRHa was detectable in frogs kept at a low temperature (4 degrees C).
mesh_terms: D000818:Animals; D002064:Buserelin / Q000494:pharmacology*; D007016:Hypophysectomy; D066298:In Vitro Techniques; D008297:Male; D010906:Pituitary Hormone-Releasing Hormones / Q000502:physiology*; D011893:Rana esculenta; D013696:Temperature; D013737:Testis / Q000378:metabolism*; D013739:Testosterone / Q000096:biosynthesis*
chemical_list: D010906:Pituitary Hormone-Releasing Hormones; D013739:Testosterone; D002064:Buserelin