title: Analysis of micronucleus induction of pyrimethamine in in vitro CHL cells and in in vivo mouse bone marrow cells.
abstract: In vivo and in vitro mutagenicity of pyrimethamine were examined in the micronucleus test. Pyrimethamine strongly induced micronuclei in a dose-dependent manner in the in vitro micronucleus test using the Chinese hamster lung (CHL) cell line, when treated at 0.2-1.6 micrograms/ml for 48 h. The in vivo micronucleus test was carried out in mice after the first, second, third and fourth administration of doses up to 40 mg/kg p.o. The results showed no increased frequency of micronuclei after any treatment, though pyrimethamine was shown to persist at levels > 2 micrograms/ml in plasma after a single oral administration of 50 mg/kg.
authors.affiliation: National Veterinary Assay Laboratory, Ministry of Agriculture, Forestry and Fisheries, Tokyo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Ono
authors.forename: H
authors.initials: H
authors.lastname: Yoshimura
mesh_terms: D000818:Animals; D001853:Bone Marrow / Q000187:drug effects / Q000648:ultrastructure; D002460:Cell Line; D006224:Cricetinae; D003412:Cricetulus; D008168:Lung; D008297:Male; D051379:Mice; D048629:Micronuclei, Chromosome-Defective / Q000187:drug effects*; D015162:Micronucleus Tests; D009153:Mutagens / Q000493:pharmacokinetics / Q000633:toxicity*; D011739:Pyrimethamine / Q000097:blood / Q000633:toxicity*
chemical_list: D009153:Mutagens; D011739:Pyrimethamine