[Analysis of 15-lipoxygenase activity in irradiated thymocytes]

We studied the effect of gamma-radiation on 15-lipoxygenase activity in rat thymocytes. The enzyme activity was determined as the rate of linoleic acid oxidation by the protein fraction isolated from the control and irradiated thymocytes under standard conditions. We demonstrate lipoxygenase activation immediately after irradiation of thymocytes. High lipoxygenase activity is observed in the cells for no more than an hour after irradiation. No high lipoxygenase activity later indicates that its synthesis is not directly induced by irradiation. Irradiation-induced generation of lipid peroxides can be the factor of lipoxygenase activation.