Perimysium
The perimysium is a layer of dense, irregular connective tissue that surrounds groups of muscle fibers (myocytes) to form bundles known as fascicles.
- The etymology of Perimysium: "Peri-" means "around," "-mys-" refers to muscle, and "-ium" is a word-forming element. Perimysium translates to "around muscle."
Additional Layers of Muscle Connective Tissue
For more information on the epimysium, perimysium, and endomysium (including a video lecture), check out:
The Function of the Perimysium:
The perimysium plays a crucial role in organizing and supporting muscle fibers, by bundling muscle cells (muscle fibers) into fascicles. Key functions include:
- Structural Support: The perimysium surrounds each fascicle, maintaining its structure and aiding in the alignment of muscle fibers within the bundle. This structural organization enhances the efficiency of muscle contractions by ensuring that fibers contract with a similar vector.
- Force Transmission: The perimysium aids in the transfer of force from individual muscle fibers to other layers of connective tissue and, ultimately, the tendons that exert force on bones.
- Pathway for Blood Vessels and Nerves: The perimysium contains blood vessels and nerves that supply the fascicles with adequate nutrient delivery, waste removal, and nerves responsible for initiating contraction.
- Protective Barrier: The perimysium provides a layer of protection for the muscle fibers within each fascicle, resisting external forces and reducing excessive motion that may otherwise cause damage during contraction.