New studies on the neural crest origin of the avian ultimobranchial glandular cells—Interspecific combinations and cytochemical characterization of C cells based on the uptake of biogenic amine precursors

Chick and quail ultimobranchial glandular cells are able to take up l-Dopa from the blood since the 11th day of incubation. They synthesize dopamine and show a faint greenish fluorescence which strongly contrasts during all the embryonic development with the bright fluorescence of carotid body cells. Isotopic and isochronic grafts of neural rhombencephalic primordium from 6 to 10-somite quail embryos are implanted into chick. The the carotid body and the ultimobranchial gland of the host are invaded by quail neurectodermic cells which have respectively the same cytochemical properties than the normal quail UB and CB glandular cells regarding their ability to take up l-Dopa and their subsequent fluorogenic amine content. Quail cells can be identified from host cells by their nuclear characteristics. The present work confirms earlier findings of neural crest origin of UBG cells using the quail-chick marker system associated with electron microscopic characteristics of calcitonin cells.