Wong E, Mizisin A P, Garrett R S, Miller A L, Powell H C
Department of Pathology (Neuropathology), School of Medicine, University of California at San Diego, La Jolla 92093.
J Neurochem. 1992 Jun;58(6):2212-20. doi: 10.1111/j.1471-4159.1992.tb10966.x.
The response of aldose reductase (AR) to crush injury was studied in normal rat sciatic nerve. Enzyme activity and immunoreactivity of AR were determined at intervals of 1, 5, 14, 28, and 35 days after crush and correlated with histologic and immunocytochemical observations. During nerve degeneration in the distal segments of crushed nerves, a significant reduction in AR activity was detected. At 5 and 14 days, coincident with Schwann cell proliferation, enzyme activity decreased by nearly two- and fourfold, respectively. Although activity of AR increased by 28 days during nerve regeneration, it was not restored to normal levels at 35 days. Similar reductions were observed with the immunoblotting of the enzyme. Quantitative analysis of immunogold labelling on electron micrographs confirmed that proliferating as well as remyelinating Schwann cells contained reduced gold particle density compared to Schwann cells of noncrushed myelinated fibers. Immunoblots of P0, a marker for the degree of Schwann cell differentiation or myelination, showed that the temporal sequence of changes in P0 paralleled that of AR. Thus expression of AR is a function of differentiated or mature Schwann cells. The putative volume regulatory role of AR in Schwann cells may become superfluous during Wallerian degeneration.
在正常大鼠坐骨神经中研究了醛糖还原酶（AR）对挤压伤的反应。在挤压后1、5、14、28和35天的时间间隔测定AR的酶活性和免疫反应性，并将其与组织学和免疫细胞化学观察结果相关联。在挤压神经的远端段神经变性期间，检测到AR活性显著降低。在第5天和第14天，与雪旺细胞增殖同时发生，酶活性分别下降了近两倍和四倍。尽管在神经再生期间AR活性在28天时增加，但在35天时并未恢复到正常水平。在对该酶进行免疫印迹时也观察到了类似的降低。电子显微镜照片上免疫金标记的定量分析证实，与未挤压的有髓纤维的雪旺细胞相比，增殖以及再髓鞘化的雪旺细胞的金颗粒密度降低。雪旺细胞分化或髓鞘化程度的标志物P0的免疫印迹显示，P0变化的时间顺序与AR的时间顺序平行。因此，AR的表达是分化或成熟雪旺细胞的一种功能。在华勒氏变性期间，AR在雪旺细胞中假定的容积调节作用可能变得多余。
