Photobiogenesis and metabolism of vitamin D

Journal Article · Sun Oct 01 00:00:00 EDT 1978 · Fed. Proc.; (United States)

OSTI ID:6042553

Holick, M F; Clark, M B

Provitamin D3 (7-dehydrocholesterol) is converted to previtamin D3 by the action of ultraviolet radiation on the skin. Previtamin D3 thermally isomerizes to vitamin D3 in the skin and the vitamin is then transported to the liver on the vitamin D-binding protein. Although there are extrahepatic vitamin D-25-hydroxylases, the liver is the major site for the 25-hydroxylation of vitamin D. In response to hypocalcemia and hypophosphatemia, 25-OH-D is metabolized by a renal-cytochrome. Parathyroid hormone has clearly been shown to be a trophin for the renal synthesis of 1,25(OH)2D; however, the role and significance of the adrenal steroids, or gonadal and pituitary hormones, on the renal 25-OH-D-1alpha-hydroxylase is not well defined.

• Research Organization: Massachusetts General Hospital, Boston
• OSTI ID: 6042553
• Journal Information: Fed. Proc.; (United States), Journal Name: Fed. Proc.; (United States) Vol. 37:12; ISSN FEPRA
• Country of Publication: United States
• Language: English

Related Subjects

550200 -- Biochemistry
560110* -- Radiation Effects on Biochemicals-- (-1987)
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ADRENAL HORMONES
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
BIOSYNTHESIS
BODY
CHEMICAL REACTIONS
CHOLECALCIFEROL
DIGESTIVE SYSTEM
ELECTROMAGNETIC RADIATION
GLANDS
GONADOTROPINS
HORMONES
HYDROXYLATION
ISOMERIZATION
LIVER
METABOLISM
ORGANS
PEPTIDE HORMONES
PITUITARY HORMONES
RADIATION EFFECTS
RADIATIONS
SKIN
STEROID HORMONES
SYNTHESIS
ULTRAVIOLET RADIATION
VITAMIN D
VITAMINS