Skip to main content
U.S. flag

An official website of the United States government

The colloidal thyroxine (T4) ring as a novel biomarker of perchlorate exposure in the African clawed frog Xenopus laevis

January 1, 2006

The purpose of this study was to determine if changes in colloidal thyroxine (T4) immunoreactivity can be used as a biomarker of perchlorate exposure in amphibian thyroid tissue. Larval African clawed frogs (Xenopus laevis) were exposed to 0, 1, 8, 93, and 1131 ??g perchlorate/l for 38 and 69 days to cover the normal period of larval development and metamorphosis. The results of this study confirmed the presence of an immunoreactive colloidal T4 ring in thyroid follicles of X. laevis and demonstrated that the intensity of this ring is reduced in a concentration-dependent manner by perchlorate exposure. The smallest effective concentration of perchlorate capable of significantly reducing colloidal T4 ring intensity was 8 ??g perchlorate/l. The intensity of the immunoreactive colloidal T4 ring is a more sensitive biomarker of perchlorate exposure than changes in hind limb length, forelimb emergence, tail resorption, thyrocyte hypertrophy, or colloid depletion. We conclude that the colloidal T4 ring can be used as a sensitive biomarker of perchlorate-induced thyroid disruption in amphibians. ?? Copyright 2006 Oxford University Press.

Citation Information

Publication Year 2006
Title The colloidal thyroxine (T4) ring as a novel biomarker of perchlorate exposure in the African clawed frog Xenopus laevis
DOI 10.1093/toxsci/kfl053
Authors F. Hu, Bibek Sharma, S. Mukhi, R. Patino, J.A. Carr
Publication Type Article
Publication Subtype Journal Article
Series Title Toxicological Sciences
Series Number
Index ID 70028456
Record Source USGS Publications Warehouse
USGS Organization