Impact of PCBs on thyroid hormone directed brain development
| Autor: | Lawrence B. Hendry, Susan P. Porterfield |
|---|---|
| Rok vydání: | 1998 |
| Předmět: |
medicine.medical_specialty
Health Toxicology and Mutagenesis Deiodinase 030209 endocrinology & metabolism Biology Toxicology 030226 pharmacology & pharmacy Partial agonist 03 medical and health sciences 0302 clinical medicine Hypothyroidism Internal medicine Placenta medicine Animals Humans Receptor chemistry.chemical_classification Triiodothyronine Thyroid Public Health Environmental and Occupational Health Brain Polychlorinated Biphenyls Rats Thyroxine Enzyme medicine.anatomical_structure Endocrinology chemistry biology.protein Environmental Pollutants Hormone |
| Zdroj: | Toxicology and industrial health. 14(1-2) |
| ISSN: | 0748-2337 |
| Popis: | Thyroid hormones regulate neuronal proliferation, migration, process outgrowth, synaptic development, and myelin formation in specific brain regions. Because brain development occurs during discrete windows of time, inappropriate levels of thyroid hormones in definitive periods can produce permanent damage, the nature of which depends upon the timing and magnitude of the insult. Thyroid hormones cross the placenta and enter the brain primarily as thyroxine (T4); therefore, conditions selectively lowering serum T4levels alter brain hormone availability. Triiodothyronine (T3) is the predominant form of the hormone that binds to the receptor. T3is produced from T4in the brain by the enzyme type II, 5'-deiodinase. Polychlorinated biphenyls (PCBs) are synthetic environmental toxicants that bear a striking structural resemblance to the active thyroid hormones and can, depending upon the species, dosage, and congener used, act as agonists, antagonists, and partial agonists to thyroid hormones. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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