[Embryonic induction and development of the ultimobranchial body in the embryogenesis of amphibia].
At early embryonal and larval stages of development 7 species of amphibia have been studied. The ultimobranchial anlage and processes resulted in formation of the secretory follicle are investigated. Dynamics on changes of amount of the gland cells and the first appearance of capillaries are analyzed. In Anura and Urodela the anlage of the ultimobranchial gland develops from the epithelial lining of the pharynx behind the last branchial pocket rudiment. The gland is asymmetric and can be laid either in the right or in the left side of the body. Death of calcitonin-secreting cells is compensated at the expense of repeated anlage of follicles from the pharyngeal epithelium. The newly formed follicles can either incorporate into the existing gland, or form independent follicles. For amphibia formation of the capillary network around the gland after beginning of the follicular secretion is specific. Owing to these data, it is possible to conclude that the stimulus for the gland to become overgrown with capillaries is the beginning of calcitonin secretion.
Besova
N V
NV
Save'lev
S V
SV
D000818:Animals; D001001:Anura / Q000196:embryology* / Q000254:growth & development; D004625:Embryo, Nonmammalian / Q000166:cytology; D047108:Embryonic Development; D004627:Embryonic Induction / Q000502:physiology; D007814:Larva / Q000254:growth & development; D014460:Ultimobranchial Body / Q000196:embryology* / Q000254:growth & development; D014562:Caudata / Q000196:embryology* / Q000254:growth & development
Zakladka i razvitie u'ltimobrakhia'lnoĭ zhelezy v émbriogeneze amfibiĭ.