Manabe S, Kurihara N, Shibutani T, Wada O, Ueki A, Suzuki H
Department of Hygiene and Preventive Medicine, Faculty of Medicine, University of Tokyo, Japan.
Carcinogenesis. 1993 May;14(5):903-6. doi: 10.1093/carcin/14.5.903.
Effects of nucleic acids on the formation of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) were studied in a model system. When a mixture of a certain amount of DNA or RNA, creatinine (1 mmol) and phenylalanine (1 mmol) in 10 ml of 50 mM phosphate buffer, pH 7.4, was heated at 60 degrees C for 4 weeks in a screw-capped vial, PhIP was produced, and the yield of PhIP was dependent on the heating time as well as the dose of nucleic acid added to the mixture. However, PhIP was not detectable in the mixtures without the presence of nucleic acids. Both deoxyribonucleotides and ribonucleotides tested induced the formation of PhIP under the presence of phenylalanine and creatinine, although bases of nucleic acids such as adenine and guanine did not induce PhIP formation. Moreover, we confirmed that 2-deoxy-D-ribose as well as D-ribose induced the formation of PhIP in the presence of creatinine and phenylalanine. These results indicate that nucleic acids can induce the formation of PhIP in the presence of creatinine and phenylalanine in the model system. Our data also suggest that pentose in nucleic acids may participate in PhIP forming reactions.
在一个模型系统中研究了核酸对2-氨基-1-甲基-6-苯基咪唑并[4,5-b]吡啶（PhIP）形成的影响。当在10 ml pH 7.4的50 mM磷酸盐缓冲液中，将一定量的DNA或RNA、肌酐（1 mmol）和苯丙氨酸（1 mmol）的混合物在带螺旋盖的小瓶中于60℃加热4周时，会产生PhIP，并且PhIP的产量取决于加热时间以及添加到混合物中的核酸剂量。然而，在没有核酸的混合物中未检测到PhIP。在苯丙氨酸和肌酐存在的情况下，所测试的脱氧核糖核苷酸和核糖核苷酸均能诱导PhIP的形成，尽管核酸的碱基如腺嘌呤和鸟嘌呤不会诱导PhIP的形成。此外，我们证实，在肌酐和苯丙氨酸存在的情况下，2-脱氧-D-核糖以及D-核糖均能诱导PhIP的形成。这些结果表明，在模型系统中，核酸在肌酐和苯丙氨酸存在的情况下可诱导PhIP的形成。我们的数据还表明，核酸中的戊糖可能参与了PhIP的形成反应。
