溴脱氧尿苷对弗瑞德白血病细胞诱导的抑制作用。脱氧胞苷的逆转机制。

Bromodeoxyuridine inhibition of Friend leukemia cell induction. Mechanism of reversal by deoxycytidine.

作者信息

Bick M D

出版信息

Biochim Biophys Acta. 1977 Jun 17;476(4):279-86. doi: 10.1016/0005-2787(77)90292-1.

Abstract

Deoxycytidine (dC) reverses bromodeoxyuridine (brdUrd) inhibition of induction in Friend leukemia cells only if added within the first 6 h after the addition of brdUrd. dC is shown to reduce the uptake of [3H]brdUrd into both soluble nucleotide pools and DNA, substantially expand the dTTP pool, and result in a lower level of brdUrd substitution in DNA. When the conversion of dC to thymidine nucleotides is prevented in BATH medium (containing brdUrd, aminopterin, thymidine, and hypoxanthine), dC no longer reverses brdUrd inhibition. These results show that dC exerts its primary effect via alterations in thymidine pools and probably through the resultant lower substitution of brdUrd in DNA.

摘要

仅在添加溴脱氧尿苷（brdUrd）后的最初6小时内添加脱氧胞苷（dC），才能逆转其对弗瑞德白血病细胞诱导的抑制作用。结果表明，dC可减少[3H]brdUrd进入可溶性核苷酸池和DNA的摄取，大幅扩大dTTP池，并导致DNA中brdUrd的取代水平降低。当在BATH培养基（含有brdUrd、氨基蝶呤、胸腺嘧啶核苷和次黄嘌呤）中阻止dC转化为胸苷核苷酸时，dC不再逆转brdUrd的抑制作用。这些结果表明，dC通过改变胸苷池发挥其主要作用，可能是通过降低DNA中brdUrd的取代水平来实现的。