周围神经Waller变性时的信息传递方式

为了检测 Waller变性时损伤部远侧段的溃变过程是同时发生还是自切断处逐渐向远侧离心式传递 ,本实验切断大鼠坐骨神经 ,将整个远侧段分为连续的 A、B、C三段 ,A段为最靠近切断处的部位。用 c-fos免疫组化方法和 EA50 组化方法 ,比较了三段之间的形态变化和阳性细胞数。结果显示 ,神经切断后 2 d,A、B、C三段间 c-fos阳性细胞数量有显著差异。至第 5天 ,这种差别消失 ,各段间阳性细胞数量表达无显著差异。实验结果说明 ,周围神经切断后 ,信息传递是由近至远地发生 ,也说明 Waller变性是由近至远地发生。至于神经切断后 ,引起 c-fos表达的机制还有待进一步研究

SIGNAL TRANSDUCTION DURING WALLERIAN DEGENERATION OF RAT PERIPHERAL NERVE

The aim of the present study is to determine whether Wallerian degeneration(WD) occurs stimultaneously in all areas of the distal segment or proceeds in a centrifugal (proximal distal) fashion. The distal segment of axotomized rat sciatic nerve was removed at close postlesion intervals and divided into three consecutive segments: A, B and C with A being closest to the site of injury. We compared the cellular and molecular changes in each segment using c fos marker and EA 50 stain. The number of cells expressing c fos in each segment was counted and compared. The results show that beginning from 2 d, there is a statistically significant difference in the number of SC expressing c fos in each segment with A B C. After 5 d, the numbers of SC expressing c fos are almost equal in all segments. Our results indicate a proximal distal spread of signal transduction originats from the site of injury. The precise mechanism responsible for the activation of c fos awaits future investigation.