GENE EXPRESSION ANALYSIS OF THE SPINAL CORD UNDER CHRONIC MECHANICAL COMPRESSION USING IN-HOUSE COMPLEMENTARY DNA MICROARRAY

为了阐明慢性压缩性脊髓病进展的确切机制，我们使用cDNA芯片分析了慢性压缩性脊髓的基因表达谱。我们采用ttw小鼠作为慢性脊髓压迫的模型，这是一种自然发生C1/2水平钙化沉积的突变小鼠。用小鼠脊髓组织提取的mRNA制成荧光探针，与含有小鼠脑和神经干细胞cDNA的基因芯片杂交。我们的微阵列系统鉴定了ttw小鼠和对照小鼠脊髓中的差异表达基因后，我们用半定量RT-PCR证实了结果。cDNA微阵列芯片上的4851个基因中，1个基因（0.02%）表达量增加2倍以上，17个基因（0.35%）表达量减少2倍以下。上调基因为gephyrin （X66366）。下调的17个基因分别是细胞外超氧化物歧化酶…More （SOD3;U38261）、p34 （AF178669）、GalNAc α -2,6-唾液基转移酶V （AB028840）、葡萄糖苷酶II a亚基（U92793）、核RNA输出因子1同源基因（BC005594）、ss-spectrin (Spnb-2；M74773)、udp - n -乙酰氨基葡萄糖转移酶（AF363030）、mPACPL1 （AB030038）、HOOK1 （AF044923）、NCAML1 （AU035962）、NSPC1 （BC004952）、溶质载体家族29 （BC006812）、丝氨酸/苏氨酸蛋白激酶（AB041542）和4个未知基因（BE291425、BC003481、AU051226、AU078872）。为了确认微阵列数据，对微阵列筛选的18个基因进行半定量RT-PCR。在这18个基因中，由于半定量RT-PCR检测到gephyrin（在ttw小鼠中上调）和NSPC1（在ttw小鼠中下调）的表达水平无显著差异，因此排除了这18个基因。与我们以往关于急性脊髓损伤的研究结果相反，本研究中意外出现了少数基因在慢性脊髓受压中表达改变。急性和慢性脊髓压迫的进展机制可能存在差异。少

To elucidate precise mechanism of progression of chronic compressive myelopathy, we analyzed gene expression profile of chronically-compressed spinal cord using cDNA microarray. We employed ttw mice, which is a mutant mouse naturally develop calcified deposit at C1/2 level, as a model for chronic spinal cord compression. Fluorescent probe were made from mRNA extracted from spinal cord tissue of ttw or control mice and hybridized with cDNA microarray which contains cDNA from mouse brain and neural stem cell. After the identification of differentially expressed genes in the spinal cords of the ttw and control mice by our microarray system, we confirmed the results using semi-quantitative RT-PCR. Among the 4,851 genes on the cDNA microarray chip, one gene (0.02%) showed increase greater than a 2-fold, and 17 genes (0.35%) showed decrease less than a 2-fold in expression. The up-regulated gene was gephyrin (X66366). The seventeen down-regulated genes were extracellular superoxide dismutase … More (SOD3;U38261), p34 (AF178669), GalNAc alpha-2,6-sialyltransferase V (AB028840), a glucosidase II a subunit (U92793), nuclear RNA export factor 1 homolog (BC005594), ss-spectrin (Spnb-2;M74773), UDP-N-acetylglucosaminyltransferase (AF363030), mPACPL1 (AB030038), HOOK1 (AF044923), NCAML1 (AU035962), NSPC1 (BC004952), solute carrier family 29 (BC006812), serine/threonine protein kinase (AB041542), and 4 unknown genes (BE291425,BC003481,AU051226,AU078872). To confirm the microarray data, semi-quantitative RT-PCR was performed for the microarray-screened 18 genes. Among those 18 genes, gephyrin (up-regulated in ttw mice) and NSPC1 (down-regulated in ttw mice) were excluded because no significant difference in expression level of those two genes was detected by semi-quantitative RT-PCR. On the contrary to the results of our previous study about acute spinal cord injury, unexpectedly small number of genes showed alteration of expression in the chronic spinal cord compression in the present study. There may be difference in mechanism of progression between acute and chronic spinal cord compression. Less