EFFECT OF IONIZING RADIATION ON p53 GENE mRNA AND PROTEIN EXPRESSIONS OF THYMOCYTES AND SPLENOCYTES IN MICE

To elucidate the molecular mechanism of G 1 arrest induced by ionizing radiation,Flow cytometry FCM and Northern blot were used to analyze p53 gene mRNA and protein expressions of thymocytes and splenocytes in Kunming mice after whole body irradiation WBI with x rays. The results indicated that the percentages of p53 + cells of thymocytes in miceincreased at 1 h to 8 h after 2.0 Gy WBI. There were not significant changes of p53 mRNA level of thymocytes and splenocytes from 1 h to 48 h after 75 mGy or 2.0 Gy WBI. No dose dependent effect was found of p53 mRNA level of thymocytes or splenocytes in mice 4 h after from 0.5 to 6.0 Gy WBI. These results suggested that ionizing radiation could induce p53 protein expression via post transcriptional mechanism.