Abstract

To bridge the gap between long-term carcinogenicity tests and short-term screening assays, a medium-term liver bioassay system for rapid detection of carcinogenic agents using male F344 rats has been developed. The system is fundamentally based on the two-stage hypothesis of carcinogenesis: initiation with diethylnitrosamine (200 mg/kg, ip) is followed by test chemical administration during the second stage in combination with 2/3 partial hepatectomy. It requires only 8 weeks for the animal treatment and a further few weeks for quantitative analysis of immunohistochemically-demonstrated glutathione S-transferase placental form positive hepatic foci. A total of 277 chemicals have already been analyzed in this laboratory and the efficacy of the system for hepatocarcinogens has thereby been well established. This bioassay is particularly useful for dose-response and chemical mixture studies usually requiring large-scale experiments and also for evaluation of chemopreventive agents. Furthermore, medium-term multi-organ bioassay system, using 5 different chemical carcinogens (DEN, MNU, BBN, DMH and DHPN) has also been established for rapid detection of not only hepatocarcinogens, but also other carcinogens.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.