OBJECTIVE: To investigate the role of apoptosis in radiation-induced mouse thymus lymphocyte damage and repair and provide the basis for understanding the molecular mechanism of radiation-induced lymphocyte damage and...OBJECTIVE: To investigate the role of apoptosis in radiation-induced mouse thymus lymphocyte damage and repair and provide the basis for understanding the molecular mechanism of radiation-induced lymphocyte damage and repair as well as the prevention and treatment of acute radiation sickness. METHODS: We studied the dynamic changes of apoptosis of mouse thymus lymphocytes and the expression of bax and bcl-2 gene products after 2, 4, 6 and 8 Gy of whole body gamma-irradiation using in situ terminal labeling, DNA electrophoresis and immunohistochemical techniques. RESULTS: At the early stage after irradiation, the percentage of apoptotic lymphocytes increased rapidly in accordance with the increasing of radiation doses, while the counts of the thymus and peripheral lymphocytes decreased sharply, showing an opposite change to lymphocyte apoptosis. After 6 Gy gamma-irradiation, typical morphological characteristics of thymus apoptotic lymphocytes in early, middle and late stages were found by transmission electron microscopy. The thymus lymphocytes displayed characteristic DNA ladders 4 hr and 8 hr after 2-6 Gy gamma-irradiation,using DNA gel electrophoresis techniques. Abnormal expression of bcl-2 and bax gene products were shown in irradiated lymphocytes. CONCLUSIONS: Apoptosis plays an important role in the process of radiation-induced mouse thymus lymphocyte damage and repair. Bcl-2 and Bax proteins may regulate the process of lymphocyte apoptosis.展开更多
Objective To study the effects of electronic magnetic pulse (EMP) on peripheral lymphocytes in dogs and to explore the mechanisms of the biological effects of EMP.Methods T, TH and Ts lymphocytes were estimated by a...Objective To study the effects of electronic magnetic pulse (EMP) on peripheral lymphocytes in dogs and to explore the mechanisms of the biological effects of EMP.Methods T, TH and Ts lymphocytes were estimated by acid phosphatase cytochemistry. Apoptotic lymphocytes and Bax and Bcl-2 proteins related to apoptosis were observed with in situ terminal labeling and immunocytochemistry.Results Peripheral T lymphocyte subpopulations decreased obviously after EMP irradiation with (2 - 12) × 104 V/m. Apoptotic percentages of lymphocytes increased with the elevation of EMP doses. Ten days after different intensity radiation, the Bax protein was found to be elevated in accord with the peak value of lymphocyte apoptosis. However, Bcl-2 protein decreased obviously.Conclusion A definite field intensity EMP could induce injury to lymphocytes. Apoptosis induced by EMP is one of the main causes of peripheral lymphocyte death and leads to immunosuppression of the body.These results suggest that people should pay more attention to the injury caused by EMP, especially to the immunological functions of the body.展开更多
文摘OBJECTIVE: To investigate the role of apoptosis in radiation-induced mouse thymus lymphocyte damage and repair and provide the basis for understanding the molecular mechanism of radiation-induced lymphocyte damage and repair as well as the prevention and treatment of acute radiation sickness. METHODS: We studied the dynamic changes of apoptosis of mouse thymus lymphocytes and the expression of bax and bcl-2 gene products after 2, 4, 6 and 8 Gy of whole body gamma-irradiation using in situ terminal labeling, DNA electrophoresis and immunohistochemical techniques. RESULTS: At the early stage after irradiation, the percentage of apoptotic lymphocytes increased rapidly in accordance with the increasing of radiation doses, while the counts of the thymus and peripheral lymphocytes decreased sharply, showing an opposite change to lymphocyte apoptosis. After 6 Gy gamma-irradiation, typical morphological characteristics of thymus apoptotic lymphocytes in early, middle and late stages were found by transmission electron microscopy. The thymus lymphocytes displayed characteristic DNA ladders 4 hr and 8 hr after 2-6 Gy gamma-irradiation,using DNA gel electrophoresis techniques. Abnormal expression of bcl-2 and bax gene products were shown in irradiated lymphocytes. CONCLUSIONS: Apoptosis plays an important role in the process of radiation-induced mouse thymus lymphocyte damage and repair. Bcl-2 and Bax proteins may regulate the process of lymphocyte apoptosis.
文摘Objective To study the effects of electronic magnetic pulse (EMP) on peripheral lymphocytes in dogs and to explore the mechanisms of the biological effects of EMP.Methods T, TH and Ts lymphocytes were estimated by acid phosphatase cytochemistry. Apoptotic lymphocytes and Bax and Bcl-2 proteins related to apoptosis were observed with in situ terminal labeling and immunocytochemistry.Results Peripheral T lymphocyte subpopulations decreased obviously after EMP irradiation with (2 - 12) × 104 V/m. Apoptotic percentages of lymphocytes increased with the elevation of EMP doses. Ten days after different intensity radiation, the Bax protein was found to be elevated in accord with the peak value of lymphocyte apoptosis. However, Bcl-2 protein decreased obviously.Conclusion A definite field intensity EMP could induce injury to lymphocytes. Apoptosis induced by EMP is one of the main causes of peripheral lymphocyte death and leads to immunosuppression of the body.These results suggest that people should pay more attention to the injury caused by EMP, especially to the immunological functions of the body.
