Quantitative assessment of mammary gland development in female long evans rats following in utero exposure to atrazine

Russell C. Hovey, Pragati Sawhney Coder, Jeffrey C. Wolf, Robert L. Sielken, Merrill O. Tisde, Charles B. Breckenridge

Research output: Contribution to journalArticle

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Abstract

In this study, we quantified the effects of in utero exposure to the herbicide atrazine on subsequent mammary gland development. Atrazine was administered to pregnant female Long Evans rats from gestation days 13-19 at doses of 0, 6.5, 50, or 100 mg/kg/day. A pair-fed control group was yoked to the high-dose atrazinetreated group. Litter size was standardized to 10 pups on postnatal day (PND) 4. Whole mounts of the left fourth mammary gland and histologic sections of the right fourth gland were obtained from a subgroup of offspring on PND1, 21, 33, on day of vaginal opening (VO), or around PND65 at diestrus. A blinded, quantitative analysis of key morphological features in mammary gland whole mounts (ductal elongation, ductal network area, epithelial area, terminal end bud [TEB] incidence, and epithelial density) as well as epithelial proliferation within different parenchymal structures was conducted. There was no effect of atrazine exposure on any of the measures of mammary gland development at the maternal dose of 6.5 mg/kg/day. On PND1, ductal elongation was increased by approximately 20% (p < 0.05) in the female offspring born to dams exposed to 50 and 100 mg/kg/day atrazine, coincident with decreased epithelial proliferation in the 100 mg/kg/day group at this age. These differences were not present on PND21, or thereafter. An increased incidence of TEB in the mammary glands from females that were born to both the pair-fed and 50 mg/kg/day-treated dams at the time of VO indicated that this response was a specific result of maternal caloric restriction. Collectively, these data indicate that maternal atrazine exposure has no long-term effects on mammary gland development in female offspring beyond a transitory response to high doses at PND1.

Original languageEnglish (US)
Pages (from-to)380-390
Number of pages11
JournalToxicological Sciences
Volume119
Issue number2
DOIs
StatePublished - 2011

Fingerprint

Atrazine
Long Evans Rats
Human Mammary Glands
Rats
Dams
Elongation
Mothers
Diestrus
Maternal Exposure
Herbicides
Caloric Restriction
Litter Size
Incidence
Age Groups
Pregnancy
Control Groups
Chemical analysis

Keywords

  • Atrazine
  • Development
  • In utero
  • Mammary gland

ASJC Scopus subject areas

  • Toxicology

Cite this

Hovey, R. C., Coder, P. S., Wolf, J. C., Sielken, R. L., Tisde, M. O., & Breckenridge, C. B. (2011). Quantitative assessment of mammary gland development in female long evans rats following in utero exposure to atrazine. Toxicological Sciences, 119(2), 380-390. https://doi.org/10.1093/toxsci/kfq337

Quantitative assessment of mammary gland development in female long evans rats following in utero exposure to atrazine. / Hovey, Russell C.; Coder, Pragati Sawhney; Wolf, Jeffrey C.; Sielken, Robert L.; Tisde, Merrill O.; Breckenridge, Charles B.

In: Toxicological Sciences, Vol. 119, No. 2, 2011, p. 380-390.

Research output: Contribution to journalArticle

Hovey, Russell C. ; Coder, Pragati Sawhney ; Wolf, Jeffrey C. ; Sielken, Robert L. ; Tisde, Merrill O. ; Breckenridge, Charles B. / Quantitative assessment of mammary gland development in female long evans rats following in utero exposure to atrazine. In: Toxicological Sciences. 2011 ; Vol. 119, No. 2. pp. 380-390.
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