title: The activity of thymidine phosphorylase obtained from human uterine leiomyomas and studied in the presence of pyrimidine derivatives.
abstract: Partially purified samples of thymidine phosphorylase were obtained from four preparations of human uterine leiomyomas and uteri using the method of Yoshimura et al. (1990), Biochim. Biophys. Acta 1034, 107-113. Among the studied twelve pyrimidine derivatives, 5-bromouracil, 5-nitrouracil, 5-fluorouracil, 6-aminouracil, 4, 6-dihydroxy-5-nitropyrimidine are competitive inhibitors, while allyloxymethylthymine is an uncompetitive inhibitor of thymidine phosphorylase activity, 6-benzyl-2-thiouracil inhibits the activity of the enzyme in a mixed way. The most potent inhibitor of the thymidine phosphorylase activity is 5-bromouracil and uracil the weakest one. Stronger inhibition of these compounds on the activity of thymidine phosphorylase was found in uterine leiomyomas than in uteri.
authors.affiliation: Department of Biochemistry, Medical University of Lódź, Poland.
authors.forename: E
authors.initials: E
authors.lastname: Miszczak-Zaborska
authors.forename: K
authors.initials: K
authors.lastname: Woźniak
mesh_terms: D000328:Adult; D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology*; D005260:Female; D006801:Humans; D007700:Kinetics; D007889:Leiomyoma / Q000201:enzymology*; D008875:Middle Aged; D011743:Pyrimidines / Q000494:pharmacology; D013939:Thymidine Phosphorylase / Q000037:antagonists & inhibitors / Q000302:isolation & purification / Q000378:metabolism*; D014594:Uterine Neoplasms / Q000201:enzymology*; D014599:Uterus / Q000201:enzymology*
chemical_list: D000964:Antimetabolites, Antineoplastic; D011743:Pyrimidines; D013939:Thymidine Phosphorylase