Control of renal vitamin D hydroxylases in birds by sex hormones

Journal Article · Sun Aug 01 04:00:00 EDT 1976 · Proc. Natl. Acad. Sci. U.S.A.; (United States)

DOI:https://doi.org/10.1073/pnas.73.8.2701· OSTI ID:7156165

Tanaka, Y; Castillo, L; DeLuca, H F

Kidney homogenates from adult male Japanese quail or chickens demonstrate hydroxylase activity predominantly for the 24 rather than the 1 position of 25-hydroxyvitamin D/sub 3/ (25-hydroxycholecalciferol). A single injection of 5 mg of estradiol-17..beta.. into a male bird completely suppresses the 24-hydroxylase and greatly increases the 1-hydroxylase activity. Immature males do not respond well to estrogen alone, but they do respond well to estradiol plus testosterone. Testosterone alone has little or no effect on the hydroxylases of either species. Castrated male chickens show an estradiol response only when testosterone is also given. Optimal 24 hr responses to 5 mg of estradiol per kg in the castrate male were obtained with about 12 mg of testosterone per kg. These optimal amounts of estradiol and testerone increased the activity of 25-hydroxyvitamin D/sub 3/-1-hydroxylase approximately 225-fold (this enzyme is also known as 25-hydroxycholecalciferol 1-monooxygenase; 25-hydroxycholecaliciferol,NADPH: oxygen oxidoreductase (hydroxylating), EC1.14.13.13). These results demonstrate a strong regulation by the sex hormones of the renal vitamin D hydroxylases in birds.

• Research Organization: Univ. of Wisconsin, Madison
• OSTI ID: 7156165
• Journal Information: Proc. Natl. Acad. Sci. U.S.A.; (United States), Journal Name: Proc. Natl. Acad. Sci. U.S.A.; (United States) Vol. 73:8; ISSN PNASA
• Country of Publication: United States
• Language: English

Related Subjects

550500* -- Metabolism
59 BASIC BIOLOGICAL SCIENCES
ANDROGENS
ANDROSTANES
ANIMALS
BIOLOGICAL EFFECTS
BIRDS
BODY
CONTROL
ENZYMES
ESTRADIOL
ESTRANES
ESTROGENS
HORMONES
HYDROXY COMPOUNDS
HYDROXYLASE
KETONES
KIDNEYS
METABOLISM
ORGANIC COMPOUNDS
ORGANS
OXIDOREDUCTASES
STEROID HORMONES
STEROIDS
TESTOSTERONE
VERTEBRATES
VITAMIN D
VITAMINS