Thyroid hormone has long been known as a key developmental factor in human and model species. Insufficient thyroid hormone during development can impair the growth and maturation of diverse tissue and organ systems. One of the most serious risks associated with congenital hypothyroidism is defective brain maturation and mental retardation. However, in recent years, targeted mutagenesis of the thyroid hormone receptor genes in model species has expanded our understanding of the neurodevelopmental role of thyroid hormone to include sensory systems. The development of all of the senses may be subject to some degree of control by thyroid hormone with the auditory and visual systems being particularly sensitive. Each of these systems is characterised by unique sensory cell types and specialized anatomy that allows the detection of stimuli as different as mechanical sound waves and photons of light. Our studies have indicated that the developmental timing and nature of a given cellular response to thyroid hormone reflect the cooperative action of several genes that mediate hormone action, including genes encoding different thyroid hormone receptor isoforms and other genes encoding hormone-activating and hormone-inactivating deiodinase enzymes. The evidence suggests that one of the most fundamental roles of thyroid hormone is to promote the development of sensory function.
30 Apr - 04 May 2011
European Society of Endocrinology