Abstract
Although phosphorylation of histone H2AX is known to be a sensitive index of radiation exposure, most of the data are derived from cultured cells and little is known for different tissues in vivo. We analysed dose-response and time course of radiation-induced phosphorylation in the three tissues of mouse; spleen, liver and brain. We used Western blot analysis to quantitate the degree of phosphorylation. Almost linear dose responses were observed in the dose range of 0.5 to 20Gy when judged at 1 hr after irradiation. The induction in liver seemed less efficient. The induced phosphorylated H2AX disappeared at one day after irradiation. Thus, the response in mouse seems to be tissue-specific.