Relationship between thyroglobulin synthesis, lodine metabolism, and histogenesis in the developing rabbit fetal thyroid gland

摘要: Abstract The biosynthesis of thyroglobulin and its iodination have been studied in the rabbit fetus relation to morphogenesis structure thyroid gland. Sixteen- 28-day-old fetuses were injected intraperitoneally vivo through uterine wall with [3H]leucine 125I. Tritium-labeled proteins analyzed by sucrose gradient centrifugation dise electrophoresis, combination immunological techniques. Thyroglobulin was estimated radioimmunoassay, 127I chemical determination. first definite follicles seen electron micrographs on day 18. Colloid is not stored large amounts until 22. Proteins having antigenic sites common adult can be radio-immunogically detected thyroids 16- 17-day-old fetuses, before formation follicles, capacity collecting radioiodine appear, detectable exist glands. Low molecular weight precursors are present 18-day thyroid; they seem actively polymerize into 19S As soon as microfollicles differentiated, iodine concentrated, occurs, hormones synthesized. ability fetal gland concentrate iodide synthesize thus seems linked organization follicles.