title: Effect of u.v. rays on 7-dehydrocholesterol content in rat skin.
abstract: Long-term exposure of rat to ultraviolet irradiation affected the cholesterol metabolism in the skin. The 7-dehydrocholesterol content was increased to 1.6 times of non-irradiated rat. However, the cholesterol content was not altered. Ultraviolet-induced precholecalciferol and cholecalciferol bound with an activator protein of delta 5,7 sterol-delta 7-reductase. This observation suggested that precholecalciferol and cholecalciferol bound with an activator protein of delta 5,7 sterol-delta 7-reductase. This observation suggested that precholecalciferol and cholecalciferol inhibit the conversion of 7-dehydrocholesterol to cholesterol and accumulate 7-dehydrocholesterol. The action of ultraviolet rays on the cholesterol metabolism in the skin may be explained as the action of ultraviolet-induced precholecalciferol and cholecalciferol.
mesh_terms: D000818:Animals; D002775:Cholestadienols / Q000378:metabolism*; D002784:Cholesterol / Q000378:metabolism; D003684:Dehydrocholesterols / Q000378:metabolism* / Q000528:radiation effects; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012867:Skin / Q000378:metabolism / Q000528:radiation effects*; D014466:Ultraviolet Rays; D014807:Vitamin D / Q000378:metabolism
chemical_list: D002775:Cholestadienols; D003684:Dehydrocholesterols; D014807:Vitamin D; D002784:Cholesterol; C016705:7-dehydrocholesterol