Lång P, Schultzberg M, Andersson G
Division of Pathology, Karolinska Institutet, Huddinge University Hospital, Huddinge, Sweden.
J Histochem Cytochem. 2001 Mar;49(3):379-96. doi: 10.1177/002215540104900312.
Tartrate-resistant purple acid phosphatase (TRAP) of osteoclasts and certain cells of the monocyte-macrophage lineage belongs to the family of purple acid phosphatases (PAPs). We provide here evidence for TRAP/PAP expression in the central and peripheral nervous systems in the rat. TRAP/PAP protein was partially purified and characterized from the trigeminal ganglion, brain, and spinal cord. The TRAP activity (U/mg tissue) in these tissues was about 10-20 times lower than in bone. Reducing agents, e.g. ascorbate and ferric iron, increased the TRAP activity from the neural tissues (nTRAP) and addition of oxidizing agents completely inactivated both bone and nTRAP. The IC(50) for three known oxyanion inhibitors of TRAP/PAP was similar for bone and nTRAP with the same rank order of potency (molybdate > tungstate > phosphate). This indicates that the redox-sensitive binuclear iron center characteristic of mammalian PAPs is present also in nTRAP. Western blots of partially purified nTRAP revealed a band with the expected size of 35 kD. The expression of TRAP in the trigeminal ganglion, brain, and spinal cord was confirmed at the mRNA level by RT-PCR. In situ hybridization histochemistry demonstrated TRAP mRNA expression in small ganglion cells of the trigeminal ganglion, in alpha-motor neurons of the ventral spinal cord, and in Purkinje cells of the cerebellum. TRAP-like immunoreactivity was encountered in the cytoplasm of neuronal cell bodies in specific areas of both the central and the peripheral nervous system. Together, the data demonstrate that active TRAP/PAP is expressed in certain parts of the rat nervous system.
破骨细胞以及单核巨噬细胞系某些细胞中的抗酒石酸紫色酸性磷酸酶（TRAP）属于紫色酸性磷酸酶（PAPs）家族。我们在此提供大鼠中枢和外周神经系统中TRAP/PAP表达的证据。从三叉神经节、脑和脊髓中对TRAP/PAP蛋白进行了部分纯化和特性鉴定。这些组织中的TRAP活性（U/mg组织）比骨组织中的低约10 - 20倍。还原剂，如抗坏血酸和三价铁，可增加神经组织中的TRAP活性（nTRAP），而加入氧化剂则会使骨组织和nTRAP完全失活。三种已知的TRAP/PAP氧阴离子抑制剂的半数抑制浓度（IC50）在骨组织和nTRAP中相似，且效力顺序相同（钼酸盐>钨酸盐>磷酸盐）。这表明哺乳动物PAPs特有的氧化还原敏感双核铁中心在nTRAP中也存在。对部分纯化的nTRAP进行的蛋白质免疫印迹显示出一条预期大小为35 kD的条带。通过逆转录聚合酶链反应（RT-PCR）在mRNA水平证实了三叉神经节、脑和脊髓中TRAP的表达。原位杂交组织化学显示TRAP mRNA在三叉神经节的小神经节细胞、脊髓腹侧的α运动神经元以及小脑的浦肯野细胞中表达。在中枢和外周神经系统的特定区域，神经元细胞体的细胞质中发现了TRAP样免疫反应性。总之，这些数据表明活性TRAP/PAP在大鼠神经系统的某些部位表达。
