The transformation of cross-reinnervated slow-twitch muscle after deafferentation in the cat.
Cross-reinnervations were effected between the extensor digitorum longus and soleus muscles in the cat hind limb. At the same time dorsal root section or ganglionectomy was performed over segments L6-S1. Completeness of the deafferentation was subsequently confirmed either by dissection or by dorsal root recording. The isometric and force-velocity properties of the muscles were measured. In animals with a unilateral cross plus deafferentation the conversion of the contractile properties of the normally slow-twitch soleus to those resembling a fast-twitch muscle was typical of that seen with an intact afferent supply. In cats with a bilateral cross-reinnervation and unilateral deafferentation there was no significant difference in the degree of transformation between the two sides. It is concluded that at least for the conversion of a slow-twitch to a fast-twitch muscle afferent feedback does not play a major role.
D000344:Afferent Pathways / Q000502:physiology; D000818:Animals; D002415:Cats; D005260:Female; D005727:Ganglia, Spinal / Q000502:physiology; D006614:Hindlimb / Q000294:innervation*; D007537:Isometric Contraction; D008297:Male; D009046:Motor Neurons / Q000502:physiology; D009119:Muscle Contraction; D009132:Muscles / Q000294:innervation*; D009416:Nerve Regeneration