In vivo analysis of UV-B induced photooxidations.
Proceedings of the first NCI/EPA/NIOSH collaborative workshop: progress on joint environmental and occupational cancer studies, May 6-8, 1980, Rockville, Maryland. Kraybill HF, Blackwood IC, Freas NB, eds. Washington, DC: National Cancer Institute, Environmental Protection Agency, National Institute for Occupational Safety and Health, 1980 May; :673-676
Photooxidations induced by ultraviolet-B (UV-B) irradiation in-vivo were analyzed using cholesterol synthesized in-vivo as a substrate. Skh:hr-1 mice were injected with 0.25 microcuries of RS-(5-H-3)- mevalonic-acid (MVA), followed by in-vivo incubation for 60 minutes, either in darkness or while exposed to two fluorescent lamps at a distance of 15 centimeters. The skin was removed following incubation, and the lipids were extracted into chloroform/methanol. The steroids were separated by thin layer chromatography and analyzed by high pressure liquid chromatography using a method developed in the first phase of the study for resolution of cholesterol and the oxidation products. The major radioactive skin steroid present 1 hour after administration of MVA was cholesterol. Smaller amounts of two other radioactive compounds were present, one less polar than cholesterol and one more polar. The more polar compound was tentatively identified as 3-beta,5-alpha,6-beta- trihydroxycholesterol. The less polar compound remained to be identified. The amounts and types of more polar radioactive peaks were greater in the animals exposed to UV-B than in those not exposed to UV-B.
Invivo-study; Laboratory-animals; Analytical-methods; Ultraviolet-radiation; Photochemical-reactions; Analytical-processes; Radiation-hazards
Kraybill HF; Blackwood IC; Freas NB
Proceedings of the First NCI/EPA/NIOSH Collaborative Workshop: Progress on Joint Environmental and Occupational Cancer Studies, May 6-8, 1980, Rockville, Maryland, H. F. Kraybill, I. C. Blackwood, and N. B. Freas, Eds. National Cancer Institute, Environmental Protection Agency, National Institute for Occupational Safety and Health