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Title: Strain differences in the responsiveness between Sprague-Dawley and Fischer rats to nephropathy induced by FYX-051, a xanthine oxidoreductase inhibitor

Abstract

To determine a rat strain appropriate for carcinogenicity testing of FYX-051, a xanthine oxidoreductase inhibitor, we performed a 4-week oral toxicity study by administering 0.3, 1 and 3 mg/kg, and 1, 3 and 10 mg/kg of FYX-051 to male Sprague-Dawley (SD) and Fischer (F344) rats, respectively. Histopathology revealed that the degree of FYX-051-induced nephropathy was 3-fold stronger in SD rats than in F344 rats. Our previous study demonstrated that the key factor of species differences in FYX-051-induced nephropathy is purine metabolism. This observation led us to examine the involvement of purine metabolism in differences among two strains of rats. However, purine metabolism was proven not to be implicated as an important factor. Subsequently, other factors responsible for the strain differences were examined. FYX-051-induced increases in plasma xanthine concentrations were higher in SD rats than in F344 rats, suggesting more remarkable effects on pharmacodynamics in the former than the latter. Urinary volume was greater in F344 rats administered 10 mg/kg of FYX-051 (6.8 ml/h/kg) than in SD rats administered 3 mg/kg of FYX-051 (5.0 ml/h/kg), implying easier xanthine excretion in the former. Urinary xanthine solubility was 55 mg/dl in F344 rats aged 6 weeks, in contrast to 38 mg/dl in SDmore » rats of the same age. Also, there were no significant differences in exposure levels at the same dose between SD and F344 rats. The outcomes of exposure levels and renal histopathology in both rats suggest the possibility that F344 rats could be exposed to a 3-fold higher amount of drug than SD rats in a carcinogenicity bioassay. The present study, therefore, suggested that strain differences of nephrotoxicity were caused by the combined effects of pharmacodynamics, xanthine excretion capacity, and urinary xanthine solubility. Furthermore, these results indicate that F344 rats would be a suitable strain for the carcinogenicity study of FYX-051.« less

Authors:
 [1];  [2];  [2];  [2];  [2];  [2]
  1. Research Laboratories 2, Fuji Yakuhin Co., Ltd., 636-1 Iidashinden, Nishi-ku, Saitama 331-0068 (Japan). E-mail: L2-26899@fujiyakuhin.co.jp
  2. Research Laboratories 2, Fuji Yakuhin Co., Ltd., 636-1 Iidashinden, Nishi-ku, Saitama 331-0068 (Japan)
Publication Date:
OSTI Identifier:
20850500
Resource Type:
Journal Article
Resource Relation:
Journal Name: Toxicology and Applied Pharmacology; Journal Volume: 217; Journal Issue: 3; Other Information: DOI: 10.1016/j.taap.2006.09.015; PII: S0041-008X(06)00342-5; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; BIOASSAY; DOSES; DRUGS; EXCRETION; METABOLISM; RATS; TOXICITY

Citation Formats

Ashizawa, Naoki, Shimo, Takeo, Matsumoto, Koji, Oba, Kazuhiko, Nakazawa, Takashi, and Nagata, Osamu. Strain differences in the responsiveness between Sprague-Dawley and Fischer rats to nephropathy induced by FYX-051, a xanthine oxidoreductase inhibitor. United States: N. p., 2006. Web. doi:10.1016/j.taap.2006.09.015.
Ashizawa, Naoki, Shimo, Takeo, Matsumoto, Koji, Oba, Kazuhiko, Nakazawa, Takashi, & Nagata, Osamu. Strain differences in the responsiveness between Sprague-Dawley and Fischer rats to nephropathy induced by FYX-051, a xanthine oxidoreductase inhibitor. United States. doi:10.1016/j.taap.2006.09.015.
Ashizawa, Naoki, Shimo, Takeo, Matsumoto, Koji, Oba, Kazuhiko, Nakazawa, Takashi, and Nagata, Osamu. Fri . "Strain differences in the responsiveness between Sprague-Dawley and Fischer rats to nephropathy induced by FYX-051, a xanthine oxidoreductase inhibitor". United States. doi:10.1016/j.taap.2006.09.015.
@article{osti_20850500,
title = {Strain differences in the responsiveness between Sprague-Dawley and Fischer rats to nephropathy induced by FYX-051, a xanthine oxidoreductase inhibitor},
author = {Ashizawa, Naoki and Shimo, Takeo and Matsumoto, Koji and Oba, Kazuhiko and Nakazawa, Takashi and Nagata, Osamu},
abstractNote = {To determine a rat strain appropriate for carcinogenicity testing of FYX-051, a xanthine oxidoreductase inhibitor, we performed a 4-week oral toxicity study by administering 0.3, 1 and 3 mg/kg, and 1, 3 and 10 mg/kg of FYX-051 to male Sprague-Dawley (SD) and Fischer (F344) rats, respectively. Histopathology revealed that the degree of FYX-051-induced nephropathy was 3-fold stronger in SD rats than in F344 rats. Our previous study demonstrated that the key factor of species differences in FYX-051-induced nephropathy is purine metabolism. This observation led us to examine the involvement of purine metabolism in differences among two strains of rats. However, purine metabolism was proven not to be implicated as an important factor. Subsequently, other factors responsible for the strain differences were examined. FYX-051-induced increases in plasma xanthine concentrations were higher in SD rats than in F344 rats, suggesting more remarkable effects on pharmacodynamics in the former than the latter. Urinary volume was greater in F344 rats administered 10 mg/kg of FYX-051 (6.8 ml/h/kg) than in SD rats administered 3 mg/kg of FYX-051 (5.0 ml/h/kg), implying easier xanthine excretion in the former. Urinary xanthine solubility was 55 mg/dl in F344 rats aged 6 weeks, in contrast to 38 mg/dl in SD rats of the same age. Also, there were no significant differences in exposure levels at the same dose between SD and F344 rats. The outcomes of exposure levels and renal histopathology in both rats suggest the possibility that F344 rats could be exposed to a 3-fold higher amount of drug than SD rats in a carcinogenicity bioassay. The present study, therefore, suggested that strain differences of nephrotoxicity were caused by the combined effects of pharmacodynamics, xanthine excretion capacity, and urinary xanthine solubility. Furthermore, these results indicate that F344 rats would be a suitable strain for the carcinogenicity study of FYX-051.},
doi = {10.1016/j.taap.2006.09.015},
journal = {Toxicology and Applied Pharmacology},
number = 3,
volume = 217,
place = {United States},
year = {Fri Dec 15 00:00:00 EST 2006},
month = {Fri Dec 15 00:00:00 EST 2006}
}
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