Changes of ultrastructure of regenerative nerve fibers in response to application of sustained releasing agent FK506 / 中华创伤杂志

ABSTRACT

Objective To discuss the effect of the sustained releasing agent FK506 on the ultrastructure of the regenerative nerve fibers.Methods The new fusiform-shaped double channel nerve conduit was used for bridge the sciatic nerve defects for 10 mm in 32 Sprague-Dawley rats.The rats were divided into Group A(100μl chitin for both channels)and Group B(chitin plus FK506 for B1 and chitin plus normal saline for B2)according to different addition of the drugs.At 8 and 12 week after operation,the middle line of the regenerated nerve was observed under the transmission electron microscope.In the meantime,an analysis was done on the area of the regenerated nerve fibers(myelinated and unmyelinated),diameter and myelin thickness of the myelinated fiber axon at 8 and 16 months.Results There was not significant difference in aspects of type and number of the regenerative nerve fibers between two channels in Group A.However,the myelinated and unmyelinated fibers of the regenerative nerves were increased in Group B1,with larger area than Group B2(P ＜ 0.05).Conclusion FK506 can significantly promote the regeneration of both the myelinated and unmyelinated fibers.