title: Cellular proliferation, cell death, and liver histology in Gambusia affinis after dietary exposure to benzidine and 2-aminofluorene.
abstract: Chronic exposure to arylamines through diet and/or smoking has been associated with genetic changes and tumorigenesis. Cellular proliferation, apoptosis, and histological changes in liver tissue were investigated in Gambusia affinis (G affinis) after chronic dietary exposure to 6.9 mM and 0.069 mM concentrations of benzidine (BZ), 2-aminofluorene (2AF), and their combination for 4, 8, and 12 weeks, respectively. The proliferation assay indicated non-dose-dependent increases in cellular proliferation over the controls for all treatment groups at 4 and 12 weeks but not at 8 weeks except for the low dose of 2AF. The apoptosis assay showed effects in the low-dose group of 2AF and BZ at 4 weeks only. Hematoxylin/eosin staining of liver tissue revealed an increase in oval/spindle cell proliferation and altered foci formation in the treated groups compared with controls. These results demonstrate a mammalian-like response to 2AF and BZ in G affinis liver.
authors.affiliation: Western Michigan University, Kalamazoo, MI, USA.
authors.forename: Susan
authors.initials: S
authors.lastname: Lentz
authors.forename: Rob
authors.initials: R
authors.lastname: Eversole
authors.forename: J McHugh
authors.initials: JM
authors.lastname: Law
authors.forename: Jay C
authors.initials: JC
authors.lastname: Means
mesh_terms: D000465:Algorithms; D000818:Animals; D001560:Benzidines / Q000008:administration & dosage / Q000633:toxicity*; D015197:Carcinogenicity Tests / Q000379:methods; D002273:Carcinogens / Q000008:administration & dosage / Q000633:toxicity*; D016923:Cell Death / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects*; D003532:Cyprinodontiformes; D004032:Diet; D004305:Dose-Response Relationship, Drug; D005449:Fluorenes / Q000008:administration & dosage / Q000633:toxicity*; D020287:In Situ Nick-End Labeling; D008099:Liver / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D008297:Male; D023421:Models, Animal; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D011897:Random Allocation; D018709:Statistics, Nonparametric; D013997:Time Factors
chemical_list: D001560:Benzidines; D002273:Carcinogens; D005449:Fluorenes; D018809:Proliferating Cell Nuclear Antigen; C029876:benzidine; C012177:2-aminofluorene