Adams G E, Ahmed I, Sheldon P W, Stratford I J
Int J Radiat Oncol Biol Phys. 1984 Sep;10(9):1653-6. doi: 10.1016/0360-3016(84)90521-2.
Electron affinity as measured by the one-electron reduction potentian, E7(1), is the major factor influencing radiosensitizing efficiency in vitro. RSU 1069 has an electron affinity (E7(1) = 398 mV) similar to misonidazole; however, the ability of this compound to sensitize hypoxic cells is considerably greater in vitro than that of misonidazole, e.g., 0.2 mM RSU 1069 gives an enhancement ratio of greater than 2.0 compared to 1.4 for the same concentration of misonidazole. Radiosensitization studies with the MT tumor in vivo also showed RSU 1069 to be a more efficient sensitizer than misonidazole. An administered dose of 0.08 mg/g RSU 1069 yielded an enhancement of 1.8 to 1.9 using tumor cell survival and tumor cure as end-points. At least a 10-fold higher dose of misonidazole is required for a similar degree of sensitization. Low doses of RSU 1069 also radiosensitize the Lewis lung and B16 experimental tumors. The ability of RSU 1069 to potentiate the cytotoxic action of melphalan and other cytotoxic drugs towards the MT tumor was also examined. RSU 1069 (0.08 mg/g) given to mice 1 hour before melphalan gave an enhancement of 2.8.
通过单电子还原电位E7(1)测量的电子亲和力是影响体外放射增敏效率的主要因素。RSU 1069的电子亲和力（E7(1)=398 mV）与米索硝唑相似；然而，该化合物在体外使缺氧细胞增敏的能力比米索硝唑强得多，例如，0.2 mM的RSU 1069的增强比大于2.0，而相同浓度的米索硝唑的增强比为1.4。对MT肿瘤进行的体内放射增敏研究也表明，RSU 1069是比米索硝唑更有效的增敏剂。以肿瘤细胞存活和肿瘤治愈为终点，给予0.08 mg/g的RSU 1069剂量可使增强比达到1.8至1.9。对于类似程度的增敏，米索硝唑所需剂量至少要高10倍。低剂量的RSU 1069也能使Lewis肺癌和B16实验性肿瘤产生放射增敏作用。还研究了RSU 1069增强美法仑和其他细胞毒性药物对MT肿瘤细胞毒性作用的能力。在给予美法仑前1小时给小鼠注射RSU 1069（0.08 mg/g），增强比为2.8。
