The Fine Structure of the Endomysium, Perimysium, and Intermyofibrillar Connections in Muscle
Bovine sternomandibularis and rabbit semimembranosus muscles were prepared in buffered hypertonimc glutaraldehyde fixative. Freeze substitution methods were utilized to minimize ice crystal damages within the tissues, and samples were further prepared for scanning electron microscopy (SEM) using traditional methods. Using SEM, filamentous material was found joining adjacent myofibrils in both rabbit semimembranosus and bovine sternomandibularis muscles. These myofibrillar interconnections were found to have a periodicity between 2.1 and 2.3 um within lenght of this tissue was between 1.9 and 2.3 um. Intermyofibrillar bridges, spaced approximately 1.9 um apart, were observed within bovine sternomandibularis muscle restrained prior to fixation. Spacing between intermyofibrillar bridges was from 1.0 to 1.4 um within bovine sternomandibularis muscle unrestrained prior to fixation. Using transmission electron microscopy, bridges between adjacent myofribrils were found at or near the Z-lines.
Endomysial connective tissue contained reticular fiber rows arranged either obliquely or perpendicularly to the long axis of myofibers. Reticular fiber arrangement may be dependent upon the degree of muscle shortening. however, irrespective of the degree of restraint, periodicity between reticular fiber rows was found to be approximately 4.0 um within bovine sternomandibularis muscle and approximately 3.3 um within rabbit semimembranosus muscle.
Orcutt, M. W.; Dutson, T. R.; Wu, F. Y.; and Smith, S. B.
"The Fine Structure of the Endomysium, Perimysium, and Intermyofibrillar Connections in Muscle,"
Food Structure: Vol. 5
, Article 6.
Available at: https://digitalcommons.usu.edu/foodmicrostructure/vol5/iss1/6