DiI的特性及在周围神经示踪中的应用

目的摸索DiI在周围神经示踪中的应用技巧，探讨其物理和生物学特性。方法应用不同示踪、操作方法，行周围神经干双向DiI示踪，测量其在神经干中的扩散速度，观察评价示踪效果。结果用DiI乙醇溶液示踪、冰冻切片、低光强下直接观察效果较好；在神经干内顺行、逆行扩散速度相同，不同时间组扩散速度有差异，DiI在神经干内的扩散具有轴突特异性。结论（1）DiI在周围神经示踪中的应用方法不同于在中枢神经；（2）DiI是一种良好的荧光类双向神经示踪剂，具有轴突特异性，可以用于活体神经束路的示踪研究。

The specific properties of DiI and the applying techniques on peripheral tracing

Objective To find techniques in application of DiI on peripheral nerve tracing and explore the physical and biologic properties.Methods The different tracing methods were exerted with the DiI on the nerve trunks of brachial plexus,measured its diffusing rate and evaluated the tracing effecst.Results Optimal effects achieved when we applied 1 mmol/L ethanol solution of DiI,sectioned serially,and Visualized the section under low light intensity directly.For DiI,the rate of diffusion is the same in labeling peripheral nerve anterogradly and retrogradly.The velocities slowed down with tracing distance on.Conclusion(1)The tracing methods on peripheral nerves were different from that on the central nerves;(2)The DiI with property specific in axons,is an efficient bidirectional fluorescence axon tracer,which is suit to trace the bundles of peripheral nerves in vivo.