Morphology of connective tissue in skeletal muscle.

The arrangement and distribution of connective tissue in six different skeletal muscles and smooth muscle was examined by scanning electron microscopy. The endomysial arrangement of collagen was similar in all types of muscle and consisted of three components: (1) myocyte-myocyte connectives; (2) myocyte-capillary connectives; and (3) a weave network of collagen intimately associated with the basal laminae of the myocytes. The perimysium of the different muscles was qualitatively similar but quantitatively dissimilar. The perimysium consisted consisted of large tendon-like bundles of interwoven collagen which connected with the dense weave collagen that surrounded groups of muscles. The arrangement of the collagen in the perimysium and endomysium would explain differences in the mechanical properties of the different muscle. The contribution of the connective tissue to mechanical properties of muscle is discussed.