MATURATION OF NERVE-CONDUCTION VELOCITY AND THE EVOKED MUSCLE POTENTIAL IN THE DOG

  • 1 January 1980
    • journal article
    • research article
    • Vol. 41  (8) , 1247-1252
Abstract
Maximum nerve conduction velocity (NCV) of motor fibers in the ulnar nerve was measured in dogs ranging in age from 12 h after birth to 32 wk and older. The evoked muscle potential (EMP) resulting from ulnar nerve stimulation was recorded from an interosseous muscle and measured for latency, duration and amplitude. There was a sharp increase in NCV from 6.3 .+-. 0.28 m/s (mean .+-. SEM [standard error of the mean]) in dogs from 12 h to 1 wk of age to 59.04 .+-. 1.41 m/s in dogs 32 wk and older. Latency of the EMP, resulting from stimulating the ulnar at a proximal or a distal site, decreased markedly after birth to 4-5 wk and then more gradually until 10-12 wk. In dogs between 10-13 wk and 32 wk and older, latency increased but was never as high as in the newborn. Duration of the EMP followed a similar pattern. Amplitude increased sharply with age, resulting in a final 14- to 18-fold increase by 32 wk and older.