脊髓白质有髓和无髓神经纤维树脂切片的两种染色方法对比

目的介绍大鼠脊髓白质有髓和无髓神经纤维树脂切片的两种染色方法并比较其效果。方法灌注固定后从SD大鼠的椎管内取出脊髓，沿垂直于其长轴的方向切取2mm厚的组织块，制作甲基丙烯酸树脂包埋切片，分别用过碘酸一雪夫试剂一亮绿（PAS—G）以及过碘酸一雪夫试剂一苏木精（PAS—H）复合染色法，显示脊髓白质内的有髓和无髓神经纤维。结果两种染色方法所示有髓或无髓神经纤维的边缘，均被染成紫红色，清晰易辨。有髓神经纤维的轴突和髓鞘在PAS—G染色法中分别被染成绿色和粉红色，而在PAS—H染色法中均被染成淡蓝色。结论PAS—G复合染色法以及PAS—H复合染色法均可清晰显示脊髓白质内的有髓和无髓神经纤维，前者可更好地分辨轴突。

A comparison between two staining methods for showing myelinated and unmyelinated nerve fibers in resin sections of the white matter of rat spinal cord

Objective To introduce two staining methods for showing the myelinated and unmyelinated nerve fibers in resin sections of the white matter of spinal cord, and compare their staining effects.Methods Spinal cords were removed by laminectomy from Sprague-Dawley rats. Tissue blocks （thickness 2 mm） were obtained along the direction perpendicular to the long axis of the spinal cord and methacrylate resin-embedded sections prepared. Myelinated and unmyelinated nerve fibers in the white matter were stained with periodic acid-Schiff reagent plus brilliant green （PAS-G） and periodic acid-Schiff reagent plus hematoxylin （PAS-H）, respectively. Results With both staining methods, the boundary of myeli- nated and unmyelinated fibers was stained purple, readily distinguishable. The axon and the myelin sheath of myelinated nerve fibers were stained green and pink, respectively, using the PAS-G method, while both stained light blue using the PAS-H method. Conclusions Myelinated and unmyelinated nerve fibers can be clearly identified using both PAS-G and PAS-H methods; the former can better distin- guish the axon.