He X P, Shiosaka S, Yoshida S
Division of Structural Cell Biology, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0101, Japan.
Neurosci Res. 2001 Apr;39(4):455-62. doi: 10.1016/s0168-0102(01)00200-0.
Proteases are involved in a variety of processes including demyelination after injury to the central nervous system. Neuropsin is a serine protease, which is constitutively expressed in the neurons of the limbic system. In the present study, intrahippocampal kainate injection and enucleation were performed on adult mice. Neuropsin mRNA and protein expression was detected by in situ hybridization and immunohistochemistry. Double in situ hybridization confirmed that the mRNA expression was induced in oligodendrocytes. One day after kainate injection to the hippocampus, neuropsin mRNA was expressed, peaking 4-8 days postoperatively and disappearing at 14 days. Immunohistochemistry and immunoelectron microscopy revealed that neuropsin was expressed in the cell body of oligodendrocytes and myelin. To see if neuropsin degrades myelin protein, purified myelin was incubated with recombinant neuropsin. A decrease in the intensity of the bands of myelin basic protein was observed. These results indicate that neuropsin is involved in demyelination.
蛋白酶参与多种过程，包括中枢神经系统损伤后的脱髓鞘。神经蛋白酶是一种丝氨酸蛋白酶，在边缘系统的神经元中组成性表达。在本研究中，对成年小鼠进行海马内注射红藻氨酸和眼球摘除术。通过原位杂交和免疫组织化学检测神经蛋白酶mRNA和蛋白表达。双重原位杂交证实少突胶质细胞中mRNA表达被诱导。向海马注射红藻氨酸一天后，神经蛋白酶mRNA开始表达，术后4 - 8天达到峰值，14天时消失。免疫组织化学和免疫电子显微镜显示神经蛋白酶在少突胶质细胞和髓鞘的细胞体中表达。为了观察神经蛋白酶是否降解髓鞘蛋白，将纯化的髓鞘与重组神经蛋白酶一起孵育。观察到髓鞘碱性蛋白条带强度降低。这些结果表明神经蛋白酶参与了脱髓鞘过程。
