Dose-Rate Effects in Biomembranes

概要

論文の詳細を見る
Mice were whole body X-irradiated with different doses and different dose-rates. Directly hereafter lipid peroxidation capacity of the liver membranes was measured. The lag phase prior to rapid peroxidation was clearly shortened at higher doses and also at lower dose rates when the same dose was applied. The dose-rate effects were found at dose-rates less than 1-1.5Gy/min. With a dose-rate as low as 0.2Gy/min radiation effects on the liver with doses of 7.5 Gy could be found. The significance of these findings for cell survival after irradiation is discussed. A major part of biomembranes is made up of lipid molecules. A relation has been found between fatty acid composition and radiosensitivity in fatty acid auxotroph K-1060 strain of E. coli. It was observed that an increased number of carbon-carbon double bonds in the fatty acids corresponds with a higher radiosensitivity of the cells and radiation-induced lipid peroxidation was suggested as the underlying mechanism. The suggested process of radiation-induced lipid peroxidation in vivo is by far clear at the moment. Conflicting results are found in the literature with respect to the contents of lipid peroxides or products of lipid peroxidation in freshly isolated tissues after in vivo irradiation.
日本放射線影響学会の論文