Richards J, Nandi S
J Natl Cancer Inst. 1978 Sep;61(3):773-7.
To determine the cytotoxicity of 7,12-dimethylbenz[a]anthracene (DMBA) and N-nitroso-N-methylurea (NMU) on primary cultures of rat mammary cells, cultures were exposed to various concentrations of these carcinogens. Cytotoxicity was evident after exposure for 24 hours to as little as 0.1 microgram DMBA/ml. Cytotoxicity was evident after exposure for 2 hours with NMU at concentrations between 80 and 160 microgram/ml. Primary cultures of rat mammary cells were also examined for their ability to metabolize [3H]DMBA into water-soluble products. During a 48-hour period, mammary cells could convert 2.2% [3H]DMBA to water-soluble metabolites. The cells retained (for at least 4 days) small quantities of [3H]DMBA that were insoluble in organic solvents.
为确定7,12-二甲基苯并[a]蒽（DMBA）和N-亚硝基-N-甲基脲（NMU）对大鼠乳腺细胞原代培养物的细胞毒性，将培养物暴露于这些致癌物的不同浓度下。暴露于低至0.1微克DMBA/毫升24小时后，细胞毒性明显。暴露于浓度为80至160微克/毫升的NMU 2小时后，细胞毒性明显。还检测了大鼠乳腺细胞原代培养物将[3H]DMBA代谢为水溶性产物的能力。在48小时内，乳腺细胞可将2.2%的[3H]DMBA转化为水溶性代谢物。细胞保留了（至少4天）少量不溶于有机溶剂的[3H]DMBA。
