Braun R J, Ratko T A, Pezzuto J M, Beattie C W
Division of Surgical Oncology, University of Illinois, Chicago 60612.
Cancer Lett. 1987 Nov;37(3):345-52. doi: 10.1016/0304-3835(87)90120-0.
The present study was designed to determine whether the stage of the estrous cycle at the time of N-nitroso-N-methylurea (NMU) presentation altered DNA adduct formation and repair in the rat uterus. In uterus the rate of O6-methylguanine (O6-meGua) and 7-methylguanine (7-meGua) formation and the total yield of adducts was estrous cycle dependent. Uterine DNA from rats injected with NMU on diestrus formed O6-meGua and 7-meGua more rapidly and had significantly higher adduct levels than those rats injected on proestrus or estrus. Repair of O6-meGua and 7-meGua was also significantly faster between 1 and 24 h post-NMU in uterine DNA isolated from rats injected on diestrus compared to those injected on proestrus or estrus.
本研究旨在确定给予N-亚硝基-N-甲基脲（NMU）时的动情周期阶段是否会改变大鼠子宫中的DNA加合物形成及修复情况。在子宫中，O6-甲基鸟嘌呤（O6-meGua）和7-甲基鸟嘌呤（7-meGua）的形成速率以及加合物的总产量均依赖于动情周期。与在动情前期或动情期注射NMU的大鼠相比，在间情期注射NMU的大鼠子宫DNA形成O6-meGua和7-meGua的速度更快，加合物水平显著更高。与在动情前期或动情期注射NMU的大鼠相比，从在间情期注射NMU的大鼠分离的子宫DNA中，在给予NMU后1至24小时内，O6-meGua和7-meGua的修复速度也明显更快。
