Affiliation:
1. Department of Physiology and Endocrinology Medical College of Georgia Augusta, Georgia
Abstract
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 T4 levels alter brain hormone availability. Triiodothyronine (T3) is the predominant form of the hormone that binds to the receptor. T3 is produced from T4 in 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.
Subject
Health, Toxicology and Mutagenesis,Public Health, Environmental and Occupational Health,Toxicology
Reference103 articles.
1. Evaluation and Characterization of the Hypothyroid hyt/hyt Mouse I: Somatic and Behavioral Studies
2. 3,4,3',4'-Tetrachlorobiphenyl given to mice prenatally produces long-term decreases in striatal dopamine and receptor binding sites in the caudate nucleus
3. Almazan, G., Honegger, P., and Matthieu, J.M. (1969). "Triiodothyronine stimulation of oligodendroglial differentiation and BWL." In: The Effect of Neonatal Thyroidectomy on Myelination in the Rat Brain (A.N. Davison , J.T. Eayrs, and D.A. Wilson, eds.). Brain Res. 15:219-232.
Cited by
72 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献