Nitrotriazole(NTA)衍生物对中国仓鼠V_(79)细胞的辐射增敏作用

TA—101是一种亲水性三氮唑酰胺的衍生物.采用中国仓鼠V_(79)细胞,通过方便的形成克隆的方法评价了它的增敏活性,而且和Adams教授所赠送的MISO进行了比较.用~(60)CO7射线源照射,剂量率为0.936GY/min.增敏比(OER)由用药则无药时的存活曲线的D_(37)剂量计算.该实验的氧增比(OER)为2 5.接种效率为80±5%.TA—101的浓度为O.2,1.0和2.0mM时其 ERS,分别为1.49,2.05和2.3.实验结果表明0. 2mM TA—101无细胞毒性.TA—101的同类物即使使用5mM也未必察到明显毒性,因此TA—101.是一种有潜力的乏氧细胞辐射敏化剂.

RADIOSENSITIZATION OF CHINESE HAMSTER V79 CELLS BY A NITROTRIAZOLE DERIVATIVE, TA-101, IN VITRO

TA-101 is a hydrophilic amide derivative of nitrotriazole. The sensitizing activities were evaluated using Chinese hamster V79 cells by conventional colony formation method and comparaed with that of MISO which was kindly supplied by proffesor Adams. The irradiation was performed using a 60Co-r ray source at a dose rate of 0.936 GY/min. The enhancement ratio (ER) was calculated from D37 of survival curves with and without a sensitizer. In our experiment, oxygen enhancement ratio (OER) was 2.5. The control plating efficiencies (PE) were 80±5%. The ERs of TA-101 at the concentration of 0.2, 1.0 and 2.0 mM were 1.49, 2.05 and 2.3 respectively. The result indicates that TA-101 does not have any cytotoxicity to aeroted cells at 0.2mM. A analogue of TA-101 also exhibits no significont cytotoxicity even at 5 mM. Therefore, TA-101 is a potentially efficient radiosensitizer for hypoxic cell in vitro.