[Experimental study of intraneural circulatory changes in axonal de- and regeneration]

Two experimental studies were made of intraneural circulatory change on axonal de- and regeneration using median and ulnar nerves of the Japanese monkey. Experiment 1: Epineural suture was performed on one side, and fascicular suture was performed on the opposite side by removing the interfascicular epineurium. The regenerated axons in the fascicular suture group were fewer in number and smaller in diameter than those in the epineural suture group; this may have been the result of destruction of the interfascicular epineurium. Experiment 2: Inter- and intrafascicular blood circulation was investigated by the electric hydrogen ion gas clearance method with the following results. Blocking of a segment of the blood supply over a length of more than 20 times the nerve diameter caused circulatory disturbance of the intrafascicular blood flow and secondary axonal degeneration. Irreversible intrafascicular blood circulatory disturbance was caused by stripping of the intrafascicular epineurium. In served segments with preserved segmental blood vessels, longer segments preserved more intraneural blood flow than shorter ones.