title: Augmentation of in vitro pituitary biotransformation of testosterone due to orchidectomy and its relation to serum gonadotropins in the rat.
abstract: The biotransformation of testosterone to its metabolites by the anterior pituitary gland and the relation between the products formed and the circulating levels of LH and FSH were examined in male rats at various stages of sexual maturation. The animals were either intact controls or castrated 4 and 7 days prior to the investigation. Castration greatly increased testosterone biotransformation to its 5alpha-reduced products, but did not affect the formation of androstendione. It was concluded that castration and the eventual rise of LH-RH stimulated the 5alpha-reductase activity but not the 17beta-ol-dehydrogenase system. This is reflected in the significant relationship between the circulating gonadotropins and 5alpha-metabolites of testosterone but not androstendione.
mesh_terms: D000735:Androstenedione / Q000096:biosynthesis; D000818:Animals; D001711:Biotransformation; D002369:Castration; D005640:Follicle Stimulating Hormone / Q000032:analysis*; D007986:Luteinizing Hormone / Q000032:analysis*; D008297:Male; D010903:Pituitary Gland, Anterior / Q000502:physiology; D051381:Rats; D013739:Testosterone / Q000378:metabolism*
chemical_list: D013739:Testosterone; D000735:Androstenedione; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone