The developing human muscle: ultrastructural differences between myoblasts and fibroblasts

Revista Brasileira De Pesquisas Medicas E Biologicas
|April 1, 1980
PubMed

Insights

Electron microscopy revealed distinct stages in fetal skeletal muscle development. Myoblasts and myotubes differentiate into mature muscle fibers, with fibroblasts and collagen present early in development.

Area of Science:

  • Developmental Biology
  • Histology
  • Cell Biology

Background:

  • Skeletal muscle development involves complex cellular differentiation.
  • Distinguishing between myoblasts and fibroblasts using light microscopy can be challenging.
  • Understanding the early stages of muscle and associated structure formation is crucial.

Purpose of the Study:

  • To investigate the ultrastructural development of fetal skeletal muscle.
  • To differentiate between myoblasts and fibroblasts during muscle development.
  • To characterize the appearance and role of fibroblasts and collagen in early muscle formation.

Main Methods:

  • Electron microscopy was used to examine fetal skeletal muscle tissue.
  • Samples ranged from nine weeks to nine months of gestation.
  • Comparative ultrastructural analysis of cellular components was performed.

Main Results:

  • Between nine and eighteen weeks, developing muscle contains myoblasts (mononucleated) and myotubes (multinucleated).
  • After eighteen weeks, muscle fibers resemble adult skeletal muscle.
  • Fibroblasts and collagen fibrils are observed as early as nine weeks, with collagen found within fibroblast cytoplasm.

Conclusions:

  • Electron microscopy effectively distinguishes myoblasts from fibroblasts.
  • The development of skeletal muscle involves a transition from myoblasts/myotubes to mature muscle fibers.
  • Fibroblasts and collagen are integral components present from early stages of skeletal muscle development.

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