Morphology and histochemistry of the myotendineal junction of the rat calf muscles. Histochemical, immunohistochemical and electron-microscopic study.
The macromolecular composition and morphometry of the myotendineal junction (MTJ) of slow-twitch (type 1) and fast-twitch (type 2) muscle fibers were studied in gastrocnemius-soleus-Achilles unit of the rat. Proteoglycans and glycosaminoglycans, type III collagen, fibronectin and laminin could be detected at the myotendineal junction. Due to the membrane folding finger-like processes were seen at the MTJ. The processes of type 1 fibers were greater in size. However, due to the subdivisions the processes of type 2 muscle fibers had a significantly greater surface length per muscle cell diameter than type 1 fibers. The myotendineal endings of both fiber types had a characteristic basal lamina, which was about three times thicker than in the longitudinal site of the same muscle cells. The basal lamina of type 1 fibers at the MTJ was significantly thicker than that of type 2 fibers.
Kvist
M
M
Sports Medical Research Unit, Paavo Nurmi Center, University of Turku, Finland.
Jozsa
L
L
Kannus
P
P
Isola
J
J
Vieno
T
T
Järvinen
M
M
Lehto
M
M
D000125:Achilles Tendon / Q000033:anatomy & histology / Q000737:chemistry*; D000818:Animals; D002809:Chondroitin Sulfates / Q000032:analysis; D003094:Collagen / Q000032:analysis; D003871:Dermatan Sulfate / Q000032:analysis; D005353:Fibronectins / Q000032:analysis; D006025:Glycosaminoglycans / Q000032:analysis; D006497:Heparan Sulfate / Q000032:analysis; D006614:Hindlimb / Q000033:anatomy & histology; D007124:Immunoenzyme Techniques; D007797:Laminin / Q000032:analysis; D008297:Male; D009132:Muscles / Q000033:anatomy & histology / Q000737:chemistry*; D051381:Rats; D011919:Rats, Inbred Strains
D002809:Chondroitin Sulfates; D003094:Collagen; D003871:Dermatan Sulfate; D005353:Fibronectins; D006025:Glycosaminoglycans; D006497:Heparan Sulfate; D007797:Laminin; C038142:chondroitin sulfate glycosaminoglycan