Toxicological Sciences 68, 372-380 (2002)
Copyright © 2002 by the Society of Toxicology
ENDOCRINE TOXICOLOGY |
Comparative Responsiveness of Hypothyroxinemia and Hepatic Enzyme Induction in Long-Evans Rats Versus C57BL/6J Mice Exposed to TCDD-like and Phenobarbital-like Polychlorinated Biphenyl Congeners
,2
* Department of Environmental and Molecular Toxicology, North Carolina State University, Raleigh, North Carolina; and
Experimental Toxicology Division and
Neurotoxicology Division, MD-74B, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711
Numerous mechanisms have been postulated to explain how polyhalogenated aromatic hydrocarbons alter thyroid homeostasis with almost all data derived from studies using the rat. This study compared the sensitivity of rats and mice to polychlorinated biphenyl (PCB)-induced hypothyroxemia. Male and female C57BL/6J mice and Long-Evans rats were dosed orally for 4 consecutive days with either PCB126 (0.03–300.0 µg/kg/day) or PCB153 (0.3–300.0 mg/kg/day). Trunk blood and livers were collected 24 h after the last dose and used to determine total serum thyroxine (T4) and hepatic microsomal T4 glucuronidation activity. Hepatic microsomal ethoxyresorufin-O-deethylase (EROD) and pentoxyresorufin-O-deethylase (PROD) activities were also determined as markers for Ah receptor or phenobarbital response unit activation, respectively. PCB126 did not affect T4 in the mouse but decreased T4 (up to 50%) in the rat. PCB153 decreased T4 (up to 80%) in both the rat and the mouse. PCB126 increased EROD in both rats (12- to 22-fold) and mice (15- to 20-fold). PCB153 induced hepatic PROD activity in both rats (30-fold) and mice (4-fold). T4 glucuronidation was increased approximately 2- to 3-fold in both rats and mice treated with PCB153. PCB126 increased T4 glucuronidation 13-fold in rats but only marginally (20%) in mice at the highest doses. Western blot analysis confirmed the PCB126-induced changes in expression of UGT1A in rats and the minimal increase in mice. These data suggest that species differences in response to chemicals that induce hypothyroxinemia are due to differential induction of hepatic UGT enzymes.
Key Words: polychlorinated biphenyls; PCBs; thyroid hormones; C576J/BL mice; Long-Evans rats.
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  L. D. Lehman-McKeeman Beam Me Up Scotty: Incorporating Transporters in Physiologically Based Pharmacokinetic-Pharmacodynamic Modeling Toxicol. Sci., July 1, 2008; 104(1): 1 - 3. [Full Text] [PDF]
|
|
|
|
 |
|
 Z. Tong, H. Li, I. Goljer, O. McConnell, and A. Chandrasekaran In Vitro Glucuronidation of Thyroxine and Triiodothyronine by Liver Microsomes and Recombinant Human UDP-Glucuronosyltransferases Drug Metab. Dispos., December 1, 2007; 35(12): 2203 - 2210. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y. Kato, S.-i. Ikushiro, R. Takiguchi, K. Haraguchi, N. Koga, S. Uchida, T. Sakaki, S. Yamada, J. Kanno, and M. Degawa A Novel Mechanism for Polychlorinated Biphenyl-Induced Decrease in Serum Thyroxine Level in Rats Drug Metab. Dispos., October 1, 2007; 35(10): 1949 - 1955. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. D. McLanahan, J. L. Campbell Jr, D. C. Ferguson, B. Harmon, J. M. Hedge, K. M. Crofton, D. R. Mattie, L. Braverman, D. A. Keys, M. Mumtaz, et al. Low-Dose Effects of Ammonium Perchlorate on the Hypothalamic-Pituitary-Thyroid Axis of Adult Male Rats Pretreated with PCB126 Toxicol. Sci., June 1, 2007; 97(2): 308 - 317. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Sakai, H. Iwata, E.-Y. Kim, O. Tsydenova, N. Miyazaki, E. A. Petrov, V. B. Batoev, and S. Tanabe Constitutive Androstane Receptor (CAR) as a Potential Sensing Biomarker of Persistent Organic Pollutants (POPs) in Aquatic Mammal: Molecular Characterization, Expression Level, and Ligand Profiling in Baikal Seal (Pusa sibirica) Toxicol. Sci., November 1, 2006; 94(1): 57 - 70. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. W. Fisher, J. Campbell, S. Muralidhara, J. V. Bruckner, D. Ferguson, M. Mumtaz, B. Harmon, J. M. Hedge, K. M. Crofton, H. Kim, et al. Effect of PCB 126 on Hepatic Metabolism of Thyroxine and Perturbations in the Hypothalamic-Pituitary-Thyroid Axis in the Rat Toxicol. Sci., March 1, 2006; 90(1): 87 - 95. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y. Kato, H. Suzuki, S. Ikushiro, S. Yamada, and M. Degawa DECREASE IN SERUM THYROXINE LEVEL BY PHENOBARBITAL IN RATS IS NOT NECESSARILY DEPENDENT ON INCREASE IN HEPATIC UDP-GLUCURONOSYLTRANSFERASE Drug Metab. Dispos., November 1, 2005; 33(11): 1608 - 1612. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y. Kato, K. Haraguchi, T. Yamazaki, R. Kimura, N. Koga, S. Yamada, and M. Degawa THE DECREASE IN LEVEL OF SERUM THYROXINE BY 2,2',4,5,5'-PENTACHLOROBIPHENYL IN RATS AND MICE: NO CORRELATION WITH FORMATION OF METHYLSULFONYL METABOLITES Drug Metab. Dispos., November 1, 2005; 33(11): 1661 - 1665. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Wong, L. D. Lehman-McKeeman, M. F. Grubb, S. J. Grossman, V. M. Bhaskaran, E. G. Solon, H. S. L. Shen, R. J. Gerson, B. D. Car, B. Zhao, et al. Increased Hepatobiliary Clearance of Unconjugated Thyroxine Determines DMP 904-Induced Alterations in Thyroid Hormone Homeostasis in Rats Toxicol. Sci., April 1, 2005; 84(2): 232 - 242. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y. Kato, S. Ikushiro, K. Haraguchi, T. Yamazaki, Y. Ito, H. Suzuki, R. Kimura, S. Yamada, T. Inoue, and M. Degawa A Possible Mechanism for Decrease in Serum Thyroxine Level by Polychlorinated Biphenyls in Wistar and Gunn Rats Toxicol. Sci., October 1, 2004; 81(2): 309 - 315. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. E. Stoker, S. C. Laws, K. M. Crofton, J. M. Hedge, J. M. Ferrell, and R. L. Cooper Assessment of DE-71, a Commercial Polybrominated Diphenyl Ether (PBDE) Mixture, in the EDSP Male and Female Pubertal Protocols Toxicol. Sci., March 1, 2004; 78(1): 144 - 155. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y. Kato, K. Haraguchi, T. Yamazaki, Y. Ito, S. Miyajima, K. Nemoto, N. Koga, R. Kimura, and M. Degawa Effects of Polychlorinated Biphenyls, Kanechlor-500, on Serum Thyroid Hormone Levels in Rats and Mice Toxicol. Sci., April 1, 2003; 72(2): 235 - 241. [Abstract] [Full Text] [PDF]
|
|