Main Title |
Dose-Response Relationships in Mice Following Subchronic Exposure to 2,3,7,8-Tetrachlorodibenzo-p-dioxin: CYP1A1, CYP1A2, Estrogen Receptor, and Protein Tyrosine Phosphorylation. |
Author |
DeVito, M. J. ;
Ma, X. ;
Babish, J. G. ;
Menache, M. ;
Birnbaum., L. S. ;
|
CORP Author |
North Carolina Univ. at Chapel Hill. Center for Environmental Medicine and Lung Biology. ;Paracelsian, Inc., Ithaca, NY. Cellular Physiology Section. ;New York State Coll. of Veterinary Medicine, Ithaca. ;Duke Univ. Medical Center, Durham, NC. Center for Extrapolation Modelling.;Health Effects Research Lab., Research Triangle Park, NC. Environmental Toxicology Div. |
Publisher |
c1994 |
Year Published |
1994 |
Report Number |
EPA-R-817643 ;EPA-R-813113; EPA/600/J-94/196; |
Stock Number |
PB94-163755 |
Additional Subjects |
Tetrachlorodibenzodioxin ;
Toxicity ;
Cytochrome P-450 ;
Estrogen receptors ;
Tyrosine ;
Dose-response relationships ;
Phosphorylation ;
Liver ;
Lung ;
Skin(Anatomy) ;
Reprint ;
|
Holdings |
Library |
Call Number |
Additional Info |
Location |
Last Modified |
Checkout Status |
NTIS |
PB94-163755 |
Some EPA libraries have a fiche copy filed under the call number shown. |
|
07/26/2022 |
|
Collation |
10p |
Abstract |
The dose-response relationships for different endpoints in different tissues were compared in response to 2,3,7,8-tetrachlorodibenzodioxin (TCDD) treatment. TCDD was administered 5 days/week for 13 weeks at doses ranging from 1.5 - 150 ng/kg/day to female B6C3F1 mice. Ethoxyresorufin-O-deethylase (EROD) activity was increased in liver, lung and skin at doses as low as 1.5 ng/kg/day. EROD activity did not attain maximal induction. Liver acetanilide-4-hydroxylase activity was induced at doses as low as 1.5 ng/kg/d and reached maximal induction at 45 ng/kg/d. TCDD treatment significantly increased the amount of three phosphotyrosyl proteins in liver S-20 fractions. Changes in phosphotyrosyl proteins reached maximal induction at 4.5 ng/kg/d. Hepatic and uterine estrogen receptor levels were unchanged at any of the doses tested. These data indicate that TCDD produces multiple effects with multiple dose-response curves suggesting that there are events in addition to receptor binding that are endpoint-specific, leading to different dose-response relationships. |