Study of motor units innervated by common peroneal nerve in monkey

ABSTRACT

The average number and size of motor units were assessed by investigating the components of motor units supplied by Common Peroneal Nerve in monkey [macaca mulatta]. The motoneurons forming the common peroneal nerve [CPN] localized by horseradish peroxidase neuronal tracing technique extended from the caudal part of L[4] to the caudal part of L[6] segments of the spinal cord. The average somal diameter of motoneurons ranged between 14 and 78 m. The motoneurons measuring more than 38 [micro]m [presumably the alpha neurons] were 69.23%. The motor end-plates on skeletal myofibres of muscles supplied by the CPN were localized by using Bromo-indigo and urea-silver technique. The average number of motor units was assessed as the ratio between the number of motoneurons and the motor endplates. The total of 992 motor units with the size of 157 of the muscles innervated by the CPN have been observed in the present study