ORIGIN OF THE REGENERATING AXONS AFTER END TO SIDE NEURORRHAPHY OF PERIPHERAL NERVE:AN EXPERIMENTAL STUDY IN RATS

Objective: To explore the origin of the regenerating axons that grow into peroneal nerve after end to side neurorrhaphy of peripheral nerve. Methords: The left peroneal nerve of Wistar rats was transected, and its distal stump was sutured end to side to a window that opened by removing the epineural sheath on the tibial nerve trunk. At 8 weeks after operation, the tibial and peroneal nerve trunks were labeled by being injected with fast blue and nuclear yellow respectively. The labeled cells in the dorsal root ganglia (DRG) were observed by fluorescence microscopy. The tibial and peroneal nerve trunks close to the location of suture were dissected, osmium stained and observed by light microscopy. Results: No double labeled cell was seen in DRGin the experimental group. Light microscopy clearly revealed that the regenerating axons in the left peroneal nerve axons(experimental group)came down from the proximal tibial or sciatic nerve stump.Conclusion: We failed to show that regenerating axons of the peroneal nerve after end to side neurorrhaphy of peripheral nerve were originated from the tibial nerve by collateral sprouting. The results of this study suggest that the regenerating axons may be derived from the growth cone of injured tibial nerve or the growth cone of the injured peroneal nerve.