Freely transplanted peroneus longus muscle in the cat reinnervated by a single nerve: physiological properties.

Physiological properties (tetanic tension, single twitch, fatigability) of free autologous muscle transplants in cats were examined in vivo five months after transplantation. After 2 weeks denervation the peroneus longus muscle was placed isometrically in the abdomen with the omentum around the muscle and with the proximal end of a cut branch of the femoral nerve attached to the muscle. (In one case a sensory nerve was used.) Five months after transplantation the function of the muscle was controlled in vivo by nerve stimulation. In the case when a sensory nerve was connected to the muscle no contraction was obtained upon indirect or direct stimulation. All the other muscles contracted when the nerve was stimulated. The mean maximum tetanic tension was 16% of the mean for the control. The twitch-time was about the same as in the control muscle but the contraction time was longer and the half relaxation time shorter compared with the control. The transplanted muscles fatigued more slowly than the normal peroneus longus muscles. In spite of the unphysiological placement of the muscles in the abdomen where they have no natural function to fulfil, they became reinnervated and contracted as late as five months after transplantation.