Objective  

To screen and identify differentially expressed genes in the dorsal root ganglion (DRG) in early experimental diabetic rats.

Methods  

Diabetic model rats were induced by single intraperitoneal injection of streptozotocin (STZ). At the second week after STZ injection, the sensory nerve conduction velocities (SNCV) of sciatic nerve were measured as an indicator of neuropathy. The technique of silver-staining mRNA differential display polymerase chain reaction (DD-PCR) was used to detect the levels of differentially expressed genes in rat DRG. The cDNA fragments that displayed differentially were identified by reverse-hybridization, cloned and sequenced subsequently, and then confirmed by Northern blot.

Results  

The SNCV in the diabetic model group [n = 9, (45.25±10.38) m/s] reduced obviously compared with the control group [n = 8, (60.10±11.92) m/s] (P < 0.05). Seven distinct cDNA clones, one was up-regulated gene and the others were down-regulated ones, were isolated by silver-staining mRNA differential display method and confirmed by Northern blot. According to the results of sequence alignment with GenBank data, majority of the clones had no significant sequence similarity to previously reported genes except only one that showed high homology to 6-pyruvoyl-tetrahydropterin synthase mRNA (accession No., BC059140), which had not been reported to relate to diabetic neuropathy.

Conclusion  

These differentially expressed genes in the diabetic DRG may contribute to the pathogenesis of diabetic peripheral neuropathy.

目的  

研究糖尿病早期大鼠背根神经节(dorsal root ganglion, DRG)中基因的差异表达, 探索糖尿病神经病变相关基因。

方法  

一次性腹腔注射链脲菌素(streptozotocin, STZ)制备糖尿病模型大鼠,于造模成功后第2周, 测量其感觉神经传导速度(sensory nerve conduction velocities, SNCV), 然后运用银染差异显示逆转录聚合酶链反应法(differential display polymerase chain reaction, DD-PCR)从糖尿病模型组与对照组大鼠的DRG中获得两者差异表达的cDNA片段, 并进行反杂交筛选、 克隆测序、 DNA序列检索分析与Northern印迹验证。

结果  

糖尿病模型大鼠建模2周时, 其SNCV与对照组相比显著下降(P < 0.05)。 银染差异显示并经克隆获得7个差异片段, 一个为上调基因, 其余为下调基因。 经GenBank查询, 仅其中的上调基因的cDNA序列与6-丙酮酰四氢喋呤合酶基因(6-pyruvoyl-tetrahydropterin synthase, 序列号BC059140)高度同源, 其它差异表达片段未检出与已知基因有同源性。

结论  

这些在糖尿病早期背根神经节中差异表达的基因可能参与了糖尿病神经病变的发生发展。