神经细胞黏附分子L1在先天性巨结肠中的表达

Neural cell adhesion molecule L1 expression in different colonic segments of Hirschsprung's disease

目的:研究L 1型神经细胞黏附分子(L ICAM)基因在先天性巨结肠不同肠段的表达。方法:分别取16例先天性巨结肠患儿狭窄段和正常段平滑肌组织,经处理后提取总RNA,应用逆转录多聚酶链反应(RT-PCR)扩增目的基因和看家基因片段,观察狭窄段和正常段的L 1CAM基因的表达,并与看家基因(-βactin)在狭窄段和正常段的表达作对比。结果:16例患者正常段L ICAM和-βactin均有明显的表达,狭窄段-βactin亦有明显的表达,但L ICAM均无表达或弱表达。结论:先天性巨结肠患者狭窄段L ICAM减少的原因可能是L ICAM的mRNA的减少或缺如,并进一步引起病变段运动障碍和巨结肠发生。

Objective To investigate the changes of neural cell adhesion molecule L1 （LICAM） mRNA expression in different segments of colon in patients with Hirschsprung＇s disease. Methods Smooth muscle tissues from the diseased and normal segments of 16 patients with Hirschsprung＇s disease were isolated respectively and preserved in -80℃ refrigerator. RNA of each segment was isolated. The DNA of LICAM and a house keeper gene （β-actin） were amplified by using reverse transcription polymerase chain reaction （RT PCR） technique. Results With 28 cycles of PCR reaction, significant expression of LICAM were observed in the normal segments in all 16 patients, whereas in the diseased segments in all 16 patients, no expression of LICAM mRNA was detectable. Conclusion The cause of the lack of LICAM which results in achalasia of the diseased segments is the lack of expression of LICAM mRNA rather than the defect of translation or LICAM itself.