Brodberg R K, Mitchell M J, Smith S L, Woodruff R C
Department of Genetics, University of California at Davis 95616.
Environ Mol Mutagen. 1987;10(4):425-32. doi: 10.1002/em.2850100411.
Dimethyl sulfoxide (DMSO) used as a solvent has been observed to complicate mutagenicity screens by interacting with tested chemicals to yield false positives or negatives. We have used DMSO as a solvent in the Drosophila melanogaster recessive sex-linked lethal mutation assay and find that it reduces, but does not abolish, the detectable mutagenicity of N,N-dimethylnitrosamine (DMN). Its use as a solvent with procarbazine, another promutagen, shows no effect on mutagenicity in Drosophila. DMSO does not exhibit a general inhibitory action on microsome activity when ecdysone 20-monooxygenase activity is used as a measure of cytochrome P-450 activity. We were unable to detect the low DMN demethylase activity in the strain used. Hence, the inhibitory effect of DMSO in Drosophila at both the physiological and biological level appears to be limited and not general in action. Because DMN and DMSO are similar in structure, it is possible that DMSO is interacting with a DMN demethylase in Drosophila. This might lead to a reduction in the conversion of DMN to a mutagen. Consequently, from the results of this study and others DMSO should be used cautiously as a solvent in Drosophila mutagen screening.
已观察到用作溶剂的二甲基亚砜（DMSO）会与受试化学物质相互作用，导致产生假阳性或假阴性，从而使致突变性筛查变得复杂。我们在黑腹果蝇隐性伴性致死突变试验中使用DMSO作为溶剂，发现它会降低但不会消除N，N - 二甲基亚硝胺（DMN）的可检测致突变性。它与另一种前诱变剂丙卡巴肼一起用作溶剂时，对果蝇的致突变性没有影响。当使用蜕皮激素20 - 单加氧酶活性作为细胞色素P - 450活性的指标时，DMSO对微粒体活性没有普遍的抑制作用。我们在所用菌株中未能检测到低水平的DMN脱甲基酶活性。因此，DMSO在果蝇生理和生物学水平上的抑制作用似乎是有限的，并非普遍存在。由于DMN和DMSO结构相似，DMSO有可能与果蝇中的DMN脱甲基酶相互作用。这可能导致DMN向诱变剂的转化减少。因此，根据本研究及其他研究结果，在果蝇诱变筛查中应谨慎使用DMSO作为溶剂。
