Kautiainen A, Vaca C E, Granath F
Department of Radiobiology, Stockholm University, Sweden.
Carcinogenesis. 1993 Apr;14(4):705-8. doi: 10.1093/carcin/14.4.705.
The stability of the adducts of malonaldehyde (MA) to N-terminal valine in hemoglobin (Hb) and to guanine at N1,N2 in liver DNA was determined in vivo. Mice were injected with radiolabeled or unlabeled MA and the decay of the levels of Hb and DNA adducts was determined using the N-alkyl Edman method and the 32P-postlabeling assay respectively. The rate of adduct formation was much higher towards valine in Hb than towards guanine in DNA. The highest level of adducts to valine was observed 4 h after the treatment, whereas the corresponding level for guanine was after approximately 120 h. The adduct to guanine in DNA was significantly more stable. The estimated half-lives of the adduct to N-terminal valine in Hb and for the adduct to guanine in DNA were approximately 6 and approximately 12.5 days respectively. The persistence of DNA adducts from MA in liver indicates that this type of adduct is poorly recognized by DNA repair enzymes and thus may accumulate during chronic exposure.
在体内测定了丙二醛（MA）与血红蛋白（Hb）中N端缬氨酸以及肝脏DNA中N1、N2位鸟嘌呤加合物的稳定性。给小鼠注射放射性标记或未标记的MA，分别使用N-烷基埃德曼法和32P后标记分析法测定Hb和DNA加合物水平的衰减情况。加合物形成速率对Hb中的缬氨酸比对DNA中的鸟嘌呤高得多。处理后4小时观察到缬氨酸加合物的最高水平，而鸟嘌呤的相应水平约在120小时后出现。DNA中鸟嘌呤加合物明显更稳定。Hb中N端缬氨酸加合物和DNA中鸟嘌呤加合物的估计半衰期分别约为6天和约12.5天。肝脏中来自MA的DNA加合物的持久性表明，这种类型的加合物不易被DNA修复酶识别，因此在长期暴露过程中可能会积累。
