[Calcium in the developing skeletal muscles of the chick embryo].
The osmium-pyroantimonate technique was used for the ultrastructural study of Ca2+-localization in two types of chick embryo skeletal muscles: m. pectoralis and m. soleus. In 8- and 12-day old embryos the pyroantimonate precipitate was found on plasmalemma, condensed chromatine and ribosomes and in N-lines of I-band. During myogenesis (15-, 21-day old embryos) the calcium precipitate is redistributed from the above mentioned sites to terminal cisternae and N-line of I-band. It is proposed that calcium of N-lines may be involved in the glycogenolysis, its association with the muscle contraction occurring particularly at early developmental stages.
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002642:Chick Embryo; D003584:Cytological Techniques; D006003:Glycogen / Q000378:metabolism; D008854:Microscopy, Electron; D009132:Muscles / Q000196:embryology* / Q000378:metabolism / Q000648:ultrastructure
D006003:Glycogen; D002118:Calcium
Kal'tsiĭ v razvivaiushchikhsia skeletnykh myshtsakh kurinogo émbriona.