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Published on: November 9, 2009
THE SARCOPLASMIC RETICULUM OF STRIATED MUSCLE OF A CYCLOPOID COPEPOD
1Department of Anatomy, Harvard Medical School, Boston.
The Journal of Cell Biology
|October 30, 2009
Summary
The abdominal muscles of the copepod Macrocyclops albidus feature a complex tubular system and extensive cisternal network. This structure is linked to the muscle
Area of Science:
- Zoology
- Cell Biology
- Muscle Physiology
Background:
- The abdominal musculature of copepods, particularly Macrocyclops albidus, is known for its rapid contractile abilities.
- Understanding the ultrastructure of these muscles is key to explaining their high performance.
Purpose of the Study:
- To elucidate the fine structure of the abdominal musculature in Macrocyclops albidus using electron microscopy.
- To correlate the observed ultrastructural features with the muscle's functional properties, such as contraction speed.
Main Methods:
- Transmission electron microscopy was employed to examine the abdominal muscle fibers of Macrocyclops albidus.
- Detailed analysis of the sarcolemma, tubular systems, myofibrils, Z lines, and cisternal elements was performed.
Main Results:
- Tubules were observed to penetrate muscle fibers from the sarcolemma, forming a dense network around myofibrils.
- A complex arrangement of tubules and cisternal elements was identified, particularly at the Z lines within myofibrils.
- The complexity of the tubular system correlated with myofibrillar geometry, while cisternal development related to contraction speed.
Conclusions:
- The intricate tubular and cisternal systems in Macrocyclops albidus abdominal muscles are adaptations for rapid muscle function.
- Comparative analysis suggests that muscle ultrastructure, specifically tubular and cisternal development, is a determinant of contraction speed across different animal groups.
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