DNA DAMAGE, REPAIR, AND REPLICATION IN SELENITE-INDUCED CATARACT IN RAT LENS
DNA DAMAGE, REPAIR, AND REPLICATION IN SELENITE-INDUCED CATARACT IN RAT LENS
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DOI：
10.3109/02713689008997578
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发表时间：
1990-11-01
影响因子：
2
通讯作者：
BUNCE, GE
中科院分区：
文献类型：
--
作者：
HUANG, LL;HESS, JL;BUNCE, GE
通过测量全身给予致白内障剂量的亚硒酸盐后大鼠透镜中3 H-胸苷的掺入，体外评价DNA合成。在接受单剂量30 nmol Na 2SeO 3/g体重的大鼠晶状体中观察到的早期代谢变化中，在施用亚硒酸盐后6至12小时之间发生的透镜上皮细胞中的DNA复制减少30%。这种变化之后，到24小时复制增加了80%。与对照组相比，96 h内DNA中的胸苷掺入量保持升高。发现非程序性DNA合成约占形成的总DNA的10%，但在注射后6和24 h，亚硒酸盐处理动物的晶状体中这种推定的DNA修复增加了30%和70%。使用碱性解旋试验，亚硒酸盐处理的动物晶状体中单链DNA的比例在24小时后增加。96 h后晶状体中的DNA损伤估计值更大。透镜中DNA代谢的每个组成部分：损伤、修复和复制都受到亚硒酸盐胁迫的影响。这些变化既发生在核性白内障形成之前，也伴随着核性白内障形成。
DNA synthesis was evaluated in vitro by measuring incorporation of 3H-thymidine in rat lens following systemic delivery of a cataractogenic dose of selenite. Among early metabolic changes observed in the lenses of rats receiving a single dose of 30 nmol Na2SeO3/g body weight was a 30% decrease in DNA replication in lens epithelium occurring between 6 and 12 h after administration of the selenite. This change was followed by an 80% increase in replication by 24 h. Thymidine incorporation in DNA remained elevated compared to controls through 96 h. Unscheduled DNA synthesis was found to be approximately 10% of the total DNA formed, but there was a 30% and 70% increase of this putative DNA repair in the lenses from selenite-treated animals at 6 and 24 h after the injection. Using the alkaline unwinding assay, the proportion of single-strand DNA in lenses from selenite-treated animals increased after 24 h. This estimate of DNA damage was greater in lenses after 96 h. Each component of DNA metabolism: damage, repair, and replication, was affected by the occurrence of selenite stress in lens. These changes both preceded and accompanied nuclear cataract formation.