Sites of aspecific ATP-phosphohydrolase activity in the branchial region of chick embryos, with particular emphasis on the myogenic cell population.
The distribution pattern of unspecific ATP-phosphohydrolase (ATP-PH) activity was studied in serial sections through the branchial region of chick embryos from HH stage 14 to 27. A selective reaction was found in the prospective myogenic mesoderm of voluntary muscles of the first three branchial arches. This property initially characterized uncondensed myogenic cell populations in the mandibular and hyoid arches and appeared later on in the third arch. In each case, the positive premuscular mesoderm was closely apposed to the lateral wall of the corresponding aortic arch. Myogenic primordia retained a strong ATP-PH activity up to stage 27 when they began to segregate into smaller premuscular units. Discrete changes observed in the mandibular and hyoid blastemas suggested that non reacting cells probably of neural crest origin invade their proximal core and contribute to the subsequent pathfinding of muscular nerves. Other selective sites of ATP-PH reactivity were detected in the odd-numbered rhombomeres, rhombencephalic floorplate, notochord, arterial endothelial cells, prospective dermis and perichondrium.
Milaire
J
J
Laboratory of Human Anatomy and Embryology, Free University of Brussels, Belgium.
D000255:Adenosine Triphosphate / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000196:embryology; D001934:Branchial Region / Q000196:embryology*; D002642:Chick Embryo / Q000166:cytology / Q000201:enzymology* / Q000502:physiology; D005865:Gestational Age; D009132:Muscles / Q000196:embryology*; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism*; D014018:Tissue Distribution / Q000502:physiology
D000255:Adenosine Triphosphate; D010744:Phosphoric Monoester Hydrolases