Blood Vessels and Connective Tissue in Autotransplanted Free Muscle Grafts of the Cat

Abstract

After 2 weeks of denervation, whole leg muscles of adult cats were transplanted to intercostal spaces and removed at intervals from 5 days to 44 weeks after grafting. The connective tissue formation and capillary supply of the grafts were studied histologically and histochemically for connective tissue and ATPase. In addition, normal muscles, denervated muscles left in situ, and muscles transplanted without previous denervation were studied. During the denervation period of 2 weeks the capillary network increased slightly. During the first 6 weeks after grafting only a few, thick-walled, irregularly shaped capillaries were present in the grafts. At 8–12 weeks there was a pronounced increase in the vascular supply, coincident with reinnervation of the grafts, and after 40 weeks the capillary pattern appeared fairly normal. In the early stages a marked increase in perimysial and endomysial connective tissue took place. With increasing reinnervation a gradual disappearance of the endomysial connective tissue occurred and in the most mature grafts a minimal increase of perimysial connective tissue remained. In muscles transplanted without previous denervation, extensive fibrotic changes developed.