Koch C J, Biaglow J E
Br J Cancer Suppl. 1978 Jun;3:163-7.
Drugs which sensitize hypoxic mammalian cells to radiation damage in vitro can also affect the cellular respiration rate. This phenomenon was studied in detail to determine whether the changes in oxygen consumption occur at low oxygen concentrations and under optimal nutritional conditions. We have found that cells in tissue culture can undergo adaptive changes in respiration (electron flow) which make them insensitive to the effects of radiosensitizing drugs and even respiration uncouplers such as dinitrophenol, and the inhibitors rotenone and cyanide. At low cell densities, where nutrient depletion in the medium would be negligible, the drugs have reduced effects, particularly at low oxygen concentrations (below 40 mmHg oxygen partial pressure). Parallel cytotoxicity and growht inhibition studies indicate that most drugs are unlikely to have substantial effect on respiration at non-cytotoxic levels.
在体外使缺氧哺乳动物细胞对辐射损伤敏感的药物也会影响细胞呼吸速率。对这一现象进行了详细研究，以确定耗氧量的变化是否发生在低氧浓度和最佳营养条件下。我们发现，组织培养中的细胞可经历呼吸（电子流）的适应性变化，从而使它们对放射增敏药物甚至呼吸解偶联剂（如二硝基苯酚）以及抑制剂鱼藤酮和氰化物的作用不敏感。在细胞密度较低的情况下，培养基中的营养物质消耗可忽略不计，这些药物的作用会减弱，尤其是在低氧浓度（氧分压低于40 mmHg）时。平行的细胞毒性和生长抑制研究表明，大多数药物在非细胞毒性水平下不太可能对呼吸产生实质性影响。
