MORPHOGENESIS OF THE THYROID GLAND

摘要: Congenital hypothyroidism is mainly due to structural defects of the thyroid gland, collectively known as dysgenesis. The two most prevalent forms this condition are abnormal localization differentiated tissue (thyroid ectopia) and total absence gland (athyreosis). clinical picture dysgenesis suggests that impaired specification, proliferation survival precursor cells loss concerted movement these in a distinct spatiotemporal pattern major causes malformation. In normal development primordium first distinguished thickening anterior foregut endoderm at base prospective tongue. Subsequently, group progenitors detaches from endoderm, moves caudally ultimately differentiates into hormone-producing units, follicles, distant location site specification. higher vertebrates later stages morphogenesis characterized by shape remodeling bilobed organ integration second type derived caudal-most pharyngeal pouches will differentiate C-cells. present knowledge developmental dynamics has emerged embryonic studies chicken, mouse more recently also zebrafish. This review highlight key morphogenetic steps organogenesis pinpoint which crucial regulatory mechanisms yet be uncovered. Considering co-incidence congenital heart malformations possible interactions between cardiovascular discussed.