title: C-fin: a cultured frog tadpole tail fin biopsy approach for detection of thyroid hormone-disrupting chemicals.
abstract: There is a need for the development of a rapid method for identifying chemicals that disrupt thyroid hormone (TH) action while maintaining complex tissue structure and biological variation. Moreover, no assay to date allows a simultaneous screen of an individual's response to multiple chemicals. A cultured tail fin biopsy or C-fin assay was developed using Rana catesbeiana tadpoles. Multiple tail fin biopsies were taken per tadpole, cultured in serum-free medium, and then each biopsy was exposed to a different treatment condition. The effects of known disruptors of TH action were evaluated in the C-fin assay. Chemical exposure was performed +/- 10 nM 3,3',5-triiodothyronine and real-time quantitative polymerase chain reaction (QPCR) of two TH-responsive transcripts, TH receptor beta (TRbeta) and the Rana larval keratin type I (RLKI), was performed. Within 48 h of exposure to Triac (1-100 nM), roscovitine (0.6-60 microM), or genistein (1-100 microM), perturbations in TH signaling were detected. Tetrabromobisphenol A (TBBPA) (10-1,000 nM) showed no effect. Acetochlor (1-100 nM) elicited a modest effect on the TH-dependent induction of TRbeta transcript. These data reveal that a direct tissue effect may not be critical for TBBPA and acetochlor to disrupt TH action previously observed in intact tadpoles.
authors.affiliation: Department of Biochemistry and Microbiology, University of Victoria, P.O. Box 3055 Stn CSC, Victoria, British Columbia V8W 3P6, Canada.
authors.forename: Ashley
authors.initials: A
authors.lastname: Hinther
authors.affiliation: Department of Biochemistry and Microbiology, University of Victoria, P.O. Box 3055 Stn CSC, Victoria, British Columbia V8W 3P6, Canada.
authors.forename: Dominik
authors.initials: D
authors.lastname: Domanski
authors.affiliation: Department of Biochemistry and Microbiology, University of Victoria, P.O. Box 3055 Stn CSC, Victoria, British Columbia V8W 3P6, Canada.
authors.forename: Saadia
authors.initials: S
authors.lastname: Vawda
authors.affiliation: Department of Biochemistry and Microbiology, University of Victoria, P.O. Box 3055 Stn CSC, Victoria, British Columbia V8W 3P6, Canada.
authors.forename: Caren C
authors.initials: CC
authors.lastname: Helbing
mesh_terms: D000818:Animals; D001706:Biopsy; D052244:Endocrine Disruptors / Q000032:analysis*; D019833:Genistein / Q000494:pharmacology; D007814:Larva / Q000187:drug effects*; D011075:Polybrominated Biphenyls / Q000494:pharmacology; D011687:Purines / Q000494:pharmacology; D011892:Rana catesbeiana / Q000196:embryology; D000077546:Roscovitine; D013623:Tail; D013961:Thyroid Gland / Q000187:drug effects*; D014052:Toluidines / Q000494:pharmacology; D014284:Triiodothyronine / Q000031:analogs & derivatives / Q000037:antagonists & inhibitors / Q000494:pharmacology
chemical_list: D052244:Endocrine Disruptors; D011075:Polybrominated Biphenyls; D011687:Purines; D014052:Toluidines; D014284:Triiodothyronine; D000077546:Roscovitine; C010642:3,3',5-triiodothyroacetic acid; C043377:acetochlor; D019833:Genistein; C020806:tetrabromobisphenol A
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