We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Variations in Phytoestrogen Content between Different Mill Dates of the Same Diet Produces Significant Differences in the Time of Vaginal Opening in CD-1 Mice and F344 Rats but Not in CD Sprague-Dawley Rats.
- Authors
Thigpen, Julius E.; Setchell, Kenneth D. R.; Padilla-Banks, Elizabeth; Haseman, Joseph K.; Saunders, Hannah E.; Caviness, Gordon F.; Kissling, Grace E.; Grant, Mary G.; Forsythe, Diane B.
- Abstract
BACKGROUND: The optimum test diet and rodent species/strain for evaluating endocrine-disrupting compounds (EDCs) are critical. OBJECTIVES: We conducted studies to evaluate rodent species sensitivity and the effects of diets varying in phytoestrogen content on the time of vaginal opening (VO) in CD-1 mice, Fischer 344 (F344) rats, and CD Sprague-Dawley (S-D) rats. METHODS: Mice were weaned on postnatal day (PND) 15 and rats on PND19 and randomly assigned to control or test diets. Body weights, food consumption, and time of VO were recorded. RESULTS: The time of VO was significantly advanced in F344 rats fed diets containing daidzein and genistein, whereas these same diets did not advance VO in S-D rats. When animals were fed the AIN-76A diet spiked with genistein, time of VO was significantly advanced at all doses in CD-1 mice, at the two highest doses in F344 rats, and at the highest dose in S-D rats. The time of VO in F344 rats was more highly correlated with the phytoestrogen content than with the total metabolizable energy (ME) of 12 diets. CONCLUSIONS: The S-D rat is less sensitive to dietary phytoestrogens compared with the F344 rat or the CD-1 mouse, suggesting that the S-D rat is not the ideal model for evaluating estrogenic activity of EDCs. The profound effects of dietary phytoestrogens on the time of VO, an estrogensensitive marker, indicate that a standardized open-formula phytoestrogen-free diet containing a low ME level should be used to optimize the sensitivity of estrogenic bioassays.
- Subjects
FOOD consumption research; ENDOCRINE toxicology; ENDOCRINE disruptors; PHYTOESTROGENS; LABORATORY mice; BIOLOGICAL assay
- Publication
Environmental Health Perspectives, 2007, Vol 115, Issue 12, p1717
- ISSN
0091-6765
- Publication type
Article
- DOI
10.1289/ehp.10165