The effect of misonidazole as a hypoxic radiosensitizer at low dose.
The effect of misonidazole as a hypoxic radiosensitizer at low dose.
复制标题
米索硝唑作为低剂量低氧放射增敏剂的作用。
作者：
B. Palcic;B. Faddegon;L. Skarsgard
采用自动低剂量生存试验，测定了米索硝唑在低辐射剂量（0-6 Gy）下在培养的哺乳动物细胞中的放射增敏效果。还测量了其在高剂量辐射（0-35 Gy）下的有效性，使用常规生存试验。在这两种情况下，使用了从0到5毫米的几种浓度的药物。低剂量下的数据采用线性和二次剂量项的双参数数学方程S = e- α - d - β D2进行分析，证明该方程与所有米索硝唑浓度下的实验数据吻合良好。结果表明，二次剂量项系数β随着米索硝唑浓度的增加而显著增加，而药物对线性项系数α的影响不显著。米索硝唑的增强比（ER）显示在较低剂量下降低。本文还讨论了这一结果的临床意义。
Using an automated low dose survival assay, the radiosensitizing effectiveness of misonidazole at low radiation dose (0-6 Gy) was measured in cultured mammalian cells. Also measured was its effectiveness at high doses of radiation (0-35 Gy) using the conventional survival assay. In both cases, several concentrations of the drug from 0 to 5 mM were used. The data at low doses were analyzed by a two-parameter mathematical equation with linear and quadratic dose terms, S = e-alpha D-beta D2, which proved to be a good fit to the experimental data at all misonidazole concentrations. It is shown that whereas the coefficient of the quadratic dose term, beta, increases significantly with increasing misonidazole concentration, the drug does not significantly affect the coefficient of the linear term, alpha. The enhancement ratio (ER) of misonidazole is shown to be decreased at lower doses. The clinical implications of this result are discussed.