title: [Studies on the mechanism of cytotoxicity of 5-fluorouracil--through impairment of metabolism].
abstract: Mechanism of cytotoxicity of 5-fluorouracil (5-FU) in relation to impairment of RNA metabolism was studied. 5-FU depressed the levels of ribonucleotide reductase and thymidine kinase, which are two key enzymes in DNA synthesis, in solid AH-130 tumor when given intraperitoneally at a dose of 60 mg/kg, and this inhibition seemed to be very toxic against cells. But this dose of 5-FU exceeded the amount that could be degraded by the liver, which was much higher than the clinical dose. We concluded that the impairment of RNA metabolism caused by 5-FU played a minor role in its anti-tumor actions.
mesh_terms: D000818:Animals; D005472:Fluorouracil / Q000494:pharmacology*; D008114:Liver Neoplasms, Experimental / Q000201:enzymology* / Q000473:pathology; D008297:Male; D012334:RNA, Neoplasm / Q000096:biosynthesis*; D051381:Rats; D011919:Rats, Inbred Strains; D012264:Ribonucleotide Reductases / Q000378:metabolism*; D012513:Sarcoma, Experimental / Q000201:enzymology* / Q000473:pathology; D013937:Thymidine Kinase / Q000378:metabolism*; D013950:Thymus Gland / Q000201:enzymology
chemical_list: D012334:RNA, Neoplasm; D012264:Ribonucleotide Reductases; D013937:Thymidine Kinase; D005472:Fluorouracil