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Isolation and Quantitative Immunocytochemical Characterization of Primary Myogenic Cells and Fibroblasts from Human Skeletal Muscle
Published on: January 12, 2015
The developing human muscle: ultrastructural differences between myoblasts and fibroblasts
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.
Abstract:
Material from foetuses of nine weeks to nine months development was examined by electron microscopy to obtain some information about the various stages in the development of skeletal muscle and structures which are intimately related to it, such as blood vessels, nerves, neuromuscular spindles, fibroblasts and their product, i.e., collagen. Regarding the myoblasts and fibroblasts it was interesting to compare their ultrastructural features since there has been some difficulty in the identification of these two types of mononucleated cells by the authors which deal with light microscopy in the study of developing skeletal muscle. It was possible to note that between nine and eighteen weeks of development the muscle is different from mature skeletal muscle and is composed predominantly of two populations of muscle cells. These are the myoblasts which are mononucleated cells and the myotubes which are multinucleated muscle cells. After eighteen weeks of development there occur only muscle fibres similar to those of adult muscle. Fibroblasts also occur frequently in the developing muscle: they too are mononucleated cells. Fibroblasts and collagen fibrils are seen between the muscle cells and structures related to them as early as nine weeks of development. Bundles of collagen were also seen in the cytoplasm of fibroblasts.
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