title: Micronucleus test with potassium chromate(VI) administered intraperitoneally and orally to mice.
abstract: The effect of route of administration, intraperitoneal (i.p.) or oral gavage (p.o.), in the mouse micronucleus test was studied with K2CrO4 in 2 mouse strains (MS/Ae and CD-1). A simplified acute toxicity test to estimate the toxic dose levels of K2CrO4 showed that the LD50S were 50 mg/kg i.p. and 300 mg/kg p.o. for MS/Ae and 32 mg/kg i.p. and 180 mg/kg p.o. for CD-1. Based on results of a pilot micronucleus test to determine appropriate dose levels and the optimal sampling time, it was decided to sample bone marrow cells of both strains of mice 24 h after i.p. doses of 10-80 mg/kg and p.o. doses ranging from 20 to 320 mg/kg. K2CrO4 administered i.p. induced micronucleated polychromatic erythrocytes (MNPCEs) dose-dependently in both strains. In contrast, when administered p.o. the chemical failed to induce MNPCEs. These results suggest that this difference between i.p. and p.o. routes is related to a difference of absorption or metabolic fate of chromate in vivo.
authors.affiliation: Pharmacology and Toxicology Laboratories, Meiji Seika Kaisha Ltd., Yokohama, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Shindo
authors.forename: Y
authors.initials: Y
authors.lastname: Toyoda
authors.forename: K
authors.initials: K
authors.lastname: Kawamura
authors.forename: M
authors.initials: M
authors.lastname: Kurebe
authors.forename: H
authors.initials: H
authors.lastname: Shimada
authors.forename: C
authors.initials: C
authors.lastname: Hattori
authors.forename: S
authors.initials: S
authors.lastname: Satake
mesh_terms: D000284:Administration, Oral; D000818:Animals; D002840:Chromates / Q000008:administration & dosage* / Q000633:toxicity; D007274:Injections, Intraperitoneal; D007928:Lethal Dose 50; D008297:Male; D051379:Mice; D015162:Micronucleus Tests; D009153:Mutagens / Q000008:administration & dosage*; D010865:Pilot Projects; D017680:Potassium Compounds
chemical_list: D002840:Chromates; D009153:Mutagens; D017680:Potassium Compounds; C027373:potassium chromate(VI)