Effect of irradiation on lipid peroxidation in serum, 1

Rabbits were irradiated once with 1000R over the whole body, and the following results were obtained. 1) The whole lipid content of serum: The whole lipid content was found to have increased about 2.6 times 24 hours after irradiation, and even after a lapse of 48 hours such a tendency persisted. 2) Serum whole TBA level: 24 hours after irradiation the whole TBA level had increased markedly up to about 6.5-fold of that before irradiation. 3) Lipid content of fraction: Especially marked in the increase in triglyceride. 4) TBA level of fractionated lipid: There is seen a marked increase in cholesterol ester, which practically occupied the entire serum TBA value. Next marked was the increase in phospholipid, and quantitatively it was classified that the increases seen in triglyceride and free fatty acids are not concerned with the rise in the free fatty acid content and TBA level. 5) Serum lipid contents and TBA level in fasting: By taking the level of serum lipid 24 hours after the start of fasting as one, the serum lipid levels were studied at 48 and 72 hours after the start of fasting, and it was found that both serum lipid and TBA levels rose only very slightly. 6) Changes in fatty acids: The relative ratio of palmitic acid to the whole fatty acids increased after irradiation, and the ratios of linolic acid and linolenic acid were decreased by irradiation while by 48 hours the relative ratio of linolic acid was decreased to about 1/5 of that before irradiation, and the relative ratio of linolenic acid was markedly decreased to about 1/35. (JPN)