Repetitive Stimulation Test after Sciatic Nerve Section in the Rat

ABSTRACT

OBJECTIVE: To evaluate changes of the parameters of the compound muscle action potentials (CMAPs) in repetitive stimulation test of the distal segment after section of the rat sciatic nerve. METHOD: Twenty rats (Sprague-Dawley, 400~450 gm) were used. Under anesthesia, one side of sciatic nerve at the 1 cm distal to the ischial tuberosity was sectioned. Following section the proximal end of the distal segment of the nerve was fixed to adjacent muscle by suture. An active stimulating wire electrode was placed at 1 cm distal to the proximal end of the distal segment. Recording electrodes were mounted at the soleus subcutaneously. Recordings of the repetitive stimulation of the sciatic nerve from the soleus were obtained at 4-hours intervals until complete conduction absence. RESULTS: Mean time of complete absence of the CMAPs in the distal segment after section of the sciatic nerve was 70.0 +/-12.5 hours. There was no significant change in the amplitude or area of the CMAPs in low rate or high rate repetitive stimulation. CONCLUSION: Our results suggested that sufficient amount of acetylcholine was released in response to repetitive stimulation after nerve section in the rat.