Binding properties of halogenated biphenyls to cells and macromolecules
The interaction of polychlorinated biphenyls (PCB) with serum proteins may help explain the cellular incorporation of PCB as the effect of PCB on thyroid hormone function. PCB reduces serum thyroxine and triiodothyronine levels in rats; the mechanism for this effect is unknown. The initial distribution of PCB from blood to tissue is rapid and depends on blood perfusion and tissue affinity; however, the translocation of unmetabolized PCB from its initial storage sites to adipose tissue may depend on serum and cellular protein interactions. Therefore, the ability of PCB to displace triiodothyronine binding to albumin and antibodies, as well as the effect of binding to serum proteins as a mechanism for cellular incorporation was measured. PCB binding to albumin showed both high and low affinity binding sites. This binding was able to prevent triiodothyronine binding to albumin. The distribution of PCB inserum showed that lipoproteins contained 94% of the total /sup 14/C PCB added, while 5% of the /sup 14/C PCB was bound to albumin. The in vitro binding of /sup 14/C PCB to serum obtained from rats pretreated with PCB in their diets for 6 months showed a significant decrease (p < 0.05) in binding compared to serum from untreated controls. This reduction in binding was caused by a decrease (p < 0.05) in total serum protein. Cellular incorporation of PCB is dependent on cell type, integrity of the plasma membrane and serum proteins. The in vitro incorporation of /sup 14/C PCB was higher (p < 0.05) in liver, adrenal and adipose cells than pituitary and thyroid cells.
- Research Organization:
- Fordham Univ., New York (USA)
- OSTI ID:
- 6053722
- Resource Relation:
- Other Information: Thesis (Ph. D.)
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
59 BASIC BIOLOGICAL SCIENCES
CHLORINATED AROMATIC HYDROCARBONS
BIOCHEMISTRY
CONFIGURATION INTERACTION
TISSUE DISTRIBUTION
PROTEINS
ADIPOSE TISSUE
ALBUMINS
CARBON 14 COMPOUNDS
IN VITRO
LIPOPROTEINS
LIVER
RATS
THYROXINE
TRACER TECHNIQUES
TRIIODOTHYRONINE
AMINO ACIDS
ANIMAL TISSUES
ANIMALS
AROMATICS
BODY
CARBOXYLIC ACIDS
CHEMISTRY
CONNECTIVE TISSUE
DIGESTIVE SYSTEM
DISTRIBUTION
GLANDS
HALOGENATED AROMATIC HYDROCARBONS
HORMONES
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
LIPIDS
MAMMALS
ORGANIC ACIDS
ORGANIC CHLORINE COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC IODINE COMPOUNDS
ORGANS
PEPTIDE HORMONES
RODENTS
THYROID HORMONES
TISSUES
VERTEBRATES
560305* - Chemicals Metabolism & Toxicology- Vertebrates- (-1987)
550201 - Biochemistry- Tracer Techniques