慢传输型便秘患者结肠壁内Cajal细胞的形态学研究

目的　慢传输型便秘 (STC)患者乙状结肠壁内Cajal细胞 (ICC)的形态学研究。方法　全层铺片、冰冻切片的免疫细胞化学染色及透射电镜观察。结果　正常成人乙状结肠壁内ICC主要分布在环肌内侧面与粘膜下层之间 (ICC SM)、环肌层内 (ICC CM)、纵肌层内 (ICC LM)及肌间神经丛周围 (ICC MP)。STC乙状结肠壁内ICC的数量均较正常对照组减少 ,其中 ,ICC SM和ICC CM减少尤为显著 ,约减少 6 0 %。铺片显示ICC -MP不仅数量减少 ,且突起的分支亦减少 ,彼此间不能形成完整的细胞网络。电镜观察可见上述部位的Cajal细胞内溶酶体聚集、脂质沉积 ,ICC SM突起间的缝隙连接较小、数量减少。结论　本研究结果提示ICC的这些病理改变可能与STC的发生、发展有关 ,但是 ,ICC的减少是该病的原因还是继发性损害的结果仍有待进一步研究

Interstitial cells of Cajal in the sigmoid colon of patients with slow-transit constipation

Objective Interstitial cells of Cajal (ICCs) are critical for the generation of electrical slow waves that regulate the phasic contractile activity of gastrointestinal tract and loss of ICCs may play an important role in the etiopathogenesis of certain motility disorder. The aim of present study is to investigate the distribution of ICCs in patients with slow-transit constipation (STC). Methods ICC from sigmoid colons from patients with STC were examined in whole-mount preparations and cryo-sections by means of immunocytochemistry and transmission electron microscopy. Results In normal sigmoid colon, ICCs were mainly located in the interspace between the circular muscle layer and submucosal border, within the circular and longitudinal muscle layers and associated with myenteric nerve plexus, which were called as ICC-SM, ICC-CM, ICC-LM and ICC-MP respectively. However, ICC of sigmoid colon in STC patients were decreased in all regions mentioned above, among them ICC-SM and ICC-CM were greatly decreased by 60%. Moreover, whole-mount preparations showed that not only the number of ICC-MP was decreased down, but also the processes of ICC-MP presented fewer branches and the cellular network was broken down. Under electric microscopy, aggregation of lysosomes and lipid deposition were observed in some ICCs and gap junctions formed by ICC-SM were smaller and fewer. Conclusions The present study indicats that ICCs in the sigmoid colon may be involved in the pathogenesis of STC. Nevertheless, further studies must be done to determine whether the decrease of ICC can lead to STC or is just a secondary lesion after STC.