人工神経開発に関する実験的研究

Abstract

The artificial nerve structure should be similar to the natural nerve structure. We consider that regeneration of peripheral nerve fibers is dependent upon to contact guidance theory and nerve growth factor (N.G.F.). Polyglycolic acid (P.G.A.) fibers (1, 100-4, 300 fibers) were inserted in silicone tubes and grafted on the siatic nerves of Sprague Dawley rats. The length of P.G.A. fibers was set 10 mm and that of silicone tubes to 14 mm. The other side of siatic nerve was grafted with the autogenous nerves. Morphological changes were examined at each period (in 4, 8, 12, 16, and 28 weeks after surgery). The diameters and numbers of regenerated nerve fibers were examined. P.G.A. fibers had affinity to the axon. Schwann cells proliferated and lined along P.G.A. fibers. Axon regrows contacting with P. G. A. fibers and Schwann cells. Both their diameters and numbers increaed and they were correlated to the duration after grafting. P.G.A. grafting was inferior to autogenous nerve grafting in early stage of regeneration.But 16 weeks after surgery, we could not recognize the difference between P.G.A. grafting and autogenous nerve grafting. P.G.A. fibers absorbed entirely in 16 weeks. It suggests that P.G.A. fibers do not interrupt the growth of the axon. We observed the regenerating fibers more often in the wider space (>20 μm) than narrow space (<20 μm) among P.G.A. fibers. In view of this, the artificial material is necessary to add the skeletal structure of P.G.A. fibers and to maintain the space intact. This artificial material should be improved by further studies.