Tsukamoto I, Kojo S
Department of Food Science and Nutrition, Nara Women's University, Japan.
Biochim Biophys Acta. 1991 May 24;1074(1):52-5. doi: 10.1016/0304-4165(91)90038-i.
The injection of 5-fluorouracil to partial hepatectomized rat prevented the rise of activities of thymidylate synthase and thymidine kinase as well as DNA synthesis in 24-h regenerating liver in a dose-dependent manner. The extent of the decrease of thymidine kinase activity was more than that of thymidylate synthase level. The immunoblotting assay showed the existence of fluorodeoxyuridine monophosphate bound thymidylate synthase in 5-fluorouracil injected rat liver. These results indicate that the reduction of DNA synthesis in regenerating liver by 5-fluorouracil result from the inhibitions of the rise of activities of both thymidylate synthase and thymidine kinase, while the mechanisms in their inhibitions may be different.
向部分肝切除的大鼠注射5-氟尿嘧啶，可呈剂量依赖性地抑制24小时再生肝中胸苷酸合成酶和胸苷激酶的活性升高以及DNA合成。胸苷激酶活性降低的程度大于胸苷酸合成酶水平降低的程度。免疫印迹分析表明，在注射5-氟尿嘧啶的大鼠肝脏中存在氟脱氧尿苷单磷酸结合的胸苷酸合成酶。这些结果表明，5-氟尿嘧啶抑制再生肝中DNA合成是由于其抑制了胸苷酸合成酶和胸苷激酶活性的升高，但其抑制机制可能不同。
