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Ca+2-accumulating components in developing skeletal muscle.

C M Smalls·D Goode
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Abstract

This ultrastructural study on the localization of Ca+2 in developing skeletal muscle indicates that the formation of calcium-accumulating components begins during embryonic development. Both oxalate and pyroantimonate techniques are used to localize Ca+2 in distinct cellular components of chick pectoral and sartorius muscles. Two major sites for Ca+2 accumulation are present in ultrathin sections of embryonic and post-embryonic muscles: the terminal cisternae of the sarcoplasmic reticulum and specific lines in the I-bands. Calcium oxalate-accumulating vesicles are present in the smallest recognizable myotubes at the twelfth day of incubation, but calcium-accumulating components are not seen at myofibrillar I-band sites until the fourteenth to seventeenth days of incubation. The fact that myofibrils first form and later in development accumulate a Ca+2-binding component suggests that this Ca+2-binding component is not necessary for the formation of myofibrils, but is added to myofibrils before hatching to serve a probable regulatory role in contraction.

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Age FactorsAnimalsAntimonyCalciumChick EmbryoChickensMicroscopy, ElectronMuscle DevelopmentMusclesOsmiumOxalatesSarcoplasmic ReticulumStaining and LabelingJournal Article

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C M Smalls, D Goode. 1977. Ca+2-accumulating components in developing skeletal muscle.. https://doi.org/10.1002/jmor.1051510204

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