Interactions of halogenated industrial chemicals with transthyretin and effects on thyroid hormone levels in vivo

Previous results in experimental systems have suggested that hydroxylated PCBs may decrease thyroid hormone levels through associative interaction with transthyretin. In the present paper it was investigated whether this property was also shared by various industrial chemicals, mainly pesticides. In...

Full description

Saved in:
Bibliographic Details
Published in:Archives of toxicology 1991, Vol.65 (1), p.15-19
Main Authors: VAN DEN BERG, K. J, VAN RAAIJ, J. A. G. M, BRAGT, P. C, NOTTEN, W. R. F
Format: Article
Language:English
Subjects:
Animals
Binding, Competitive - physiology
Biological and medical sciences
Chemical and industrial products toxicology. Toxic occupational diseases
Hydrocarbons, Halogenated - metabolism
Male
Medical sciences
Prealbumin - metabolism
Protein Binding
Rats
Rats, Inbred Strains
Receptors, Thyroid Hormone - metabolism
Thyroxine - blood
Toxicology
Various organic compounds
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Previous results in experimental systems have suggested that hydroxylated PCBs may decrease thyroid hormone levels through associative interaction with transthyretin. In the present paper it was investigated whether this property was also shared by various industrial chemicals, mainly pesticides. In total, 65 compounds from 12 chemical groups were analyzed for direct interference with the T4 binding site of transthyretin using a competitive binding assay. Sixty per cent of the compounds were competitive at a concentration level of 100 microM. Relatively strong interactions were observed by several chlorophenols, chlorophenoxy acids and nitrophenols, as well as by individual compounds such as hexachlorobenzene, dicofol, bromoxynil and tetrachlorohydroquinone. Examples from these chemical groups, e.g. pentachlorophenol, 2,4-dichlorophenoxybutyric acid, dinoseb and bromoxynil, also reduced plasma TT4 levels in rats. In addition, bromoxynil decreased plasma TT3 levels. The results suggest the existence of a number of halogenated industrial chemicals with a potential for lowering plasma thyroid hormone levels through interference with hormone transport carriers.
ISSN:0340-5761
1432-0738
DOI:10.1007/BF01973497