β-1,4半乳糖基转移酶-I在钳夹伤后大鼠坐骨神经中表达的变化

为了观察β-1,4-半乳糖基转移酶-I(β-1,4-galactosyltransferase-I,β-1,4-GalT-I)在正常和钳夹伤后大鼠坐骨神经中表达的变化,本研究采用RT-PCR方法,从小鼠坐骨神经中特异性地扩增β-1,4-GalT-I cDNA片段并将其克隆到pGEM-T载体。采用体外转录的方法合成地高辛标记的正、反义β-1,4-GalT-I RNA探针。通过原位杂交和图像分析的方法,观察β-1,4-GalT-I mRNA在正常和夹伤大鼠坐骨神经中的表达及其变化。结果表明:β-1,4-GalT-I mRNA在大鼠坐骨神经的髓鞘中表达,在夹伤坐骨神经后1~2d,β-1,4-GalT-I mRNA在坐骨神经的表达最高,于夹伤后1周开始下降,在夹伤后1个月恢复至正常水平。上述结果提示坐骨神经夹伤后β-1,4-GalT-I mRNA的表达发生变化,并且主要表达在坐骨神经的Schwann细胞。本研究结果为进一步分析β-1,4-GalT-I在周围神经再生中的调控机制奠定了基础。

EXPRESSIVE CHANGES OF β-1,4-GALACTOSYLTRANSFERASE-I IN THE RAT SCIATIC NERVE AFTER NERVE INJURY

To study the potential role of β-1,4-galactosyltransferase-I (β-1,4-GalT-I) in nerve regeneration and resumption, we preliminarily investigated the expressive changes of β-1,4-GalT-I mRNA in normal and crushed sciatic nerves in the rat. We amplified the cDNA fragments of β-1,4-GalT-I in mouse sciatic nerves by RT-PCR. The products of RT-PCR were subcloned into pGEM-T vector, confirmed by sequencing, which was used to label probes for in situ hybridization. The data indicated that β-1,4-GalT-I mRNA was localized mainly in the sheath of the sciatic nerve by in situ hybridization. It was also found that the expressive changes of β-1,4-GalT-I mRNA in crushed sciatic nerves reached the peak at 1~2 days after the nerve injury and began to decrease at 1 week thereafter and returned to normal level at 1 month after the nerves injury by image analysis. These results suggest that β-1,4-GalT-I may localize mainly in Schwamn cells of the sciatic nerves. It may play a role in the peripheral nerve regeneration at the early stage after the sciatic nerve injury in the rat.