title: Micronucleus test in rodent tissues other than liver or erythrocytes: Report of the IWGT working group.
abstract: At the 6th International Workshop on Genotoxicity Testing, the liver micronucleus test (MNT) working group briefly discussed the MNT using tissues other than liver/erythrocytes. Many tissues other than liver/erythrocytes have been studied, primarily for research purposes. They have included the colon and intestinal epithelium, skin, spleen, lung, stomach, bladder, buccal mucosa, vagina, and fetal/neonatal tissues. These tissues were chosen because they were target sites of carcinogens, and/or relevant to a specific route of exposure. Recently, there has been particular focus on the gastrointestinal (GI) tract as it is a contact site associated with high exposure following oral gavage. Furthermore GI tumors are observed with high frequency in human populations. A collaborative study of the rat glandular stomach and colon MNT was conducted in conjunction with a collaborative study of the repeated-dose liver MNT. Based on limited data currently available, the rodent MNT using the glandular stomach and/or colon seems to detect genotoxic carcinogens with GI tract target-organ specificity. The working group concluded that the GI tract MNT would be a promising method to examine clastogenicity or aneugenicity of test chemicals in the stomach and/or colon. Further data will be needed to fully establish the methods, and to identify the sensitivity and specificity of the GI tract MNT.
authors.affiliation: Mitsubishi Tanabe Pharma Co., Chiba, Japan. Electronic address: Uno.Yoshifumi@ma.mt-pharma.co.jp.
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Uno
authors.affiliation: National Institute of Health Sciences, Tokyo, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Morita
authors.affiliation: National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands.
authors.forename: Mirjam
authors.initials: M
authors.lastname: Luijten
authors.affiliation: Covance Laboratories Ltd., Harrogate, UK.
authors.forename: Carol
authors.initials: C
authors.lastname: Beevers
authors.affiliation: LSI Medience (Formerly Mitsubishi Chemical Medience Co.), Ibaraki, Japan.
authors.forename: Shuichi
authors.initials: S
authors.lastname: Hamada
authors.affiliation: Daiichi Sankyo Co., Ltd., Tokyo, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Itoh
authors.affiliation: Yakult Honsha Co., Ltd., Tokyo, Japan.
authors.forename: Wakako
authors.initials: W
authors.lastname: Ohyama
authors.affiliation: LSI Medience (Formerly Mitsubishi Chemical Medience Co.), Ibaraki, Japan.
authors.forename: Hironao
authors.initials: H
authors.lastname: Takasawa
mesh_terms: D024422:Aneugens / Q000032:analysis / Q000633:toxicity; D000818:Animals; D000831:Animals, Newborn; D003106:Colon / Q000378:metabolism / Q000473:pathology; D004912:Erythrocytes / Q000378:metabolism / Q000473:pathology; D005260:Female; D005333:Fetus / Q000378:metabolism / Q000473:pathology; D005753:Gastric Mucosa / Q000378:metabolism; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism / Q000473:pathology; D008099:Liver / Q000378:metabolism / Q000473:pathology; D008297:Male; D051379:Mice; D048629:Micronuclei, Chromosome-Defective / Q000139:chemically induced*; D015162:Micronucleus Tests / Q000379:methods / Q000592:standards; D009061:Mouth Mucosa / Q000378:metabolism / Q000473:pathology; D051381:Rats; D012867:Skin / Q000378:metabolism / Q000473:pathology; D013154:Spleen / Q000378:metabolism / Q000473:pathology; D013270:Stomach / Q000473:pathology; D001743:Urinary Bladder / Q000378:metabolism / Q000473:pathology; D014621:Vagina / Q000378:metabolism / Q000473:pathology
chemical_list: D024422:Aneugens
keywords: Colon; Gastrointestinal (GI) tract; IWGT; Micronucleus test; Stomach