Regeneration of mammalian skeletal muscle following the injection of the snake-venom toxin, taipoxin

Abstract

Taipoxin, a toxin isolated from the venom of the snake Oxyuranus scutellatus was injected subcutaneously into the anterolateral aspect of one hind limb of the rat. The toxin caused a necrotising myopathy in the underlying muscle. The ultrastructural characteristics of the regeneration that followed the administration of the myotoxin were studied. Regeneration occurred within the surviving basal lamina tubes from a population of spared satellite cells. Myotubes were formed by 3 days and small immature muscle fibres by 5 days. The regenerative response was total and very rapid. Highly activated satellite cells were found in apparently undamaged fibres in the toxin-damaged muscles. Many of these cells appeared to be motile, having cytoplasmic processes which seemed to be passing through the basal lamina of the parent muscle fibres.