大鼠直肠壁内淋巴管的超微结构

The ultrastructure of intramural lymphatics in rats' rectum

目的观察大鼠直肠壁内毛细淋巴管的超微结构特点,为探讨直肠癌淋巴道转移的机制提供形态学依据。方法取30只大鼠直肠,做超薄切片,透射电镜观察。结果毛细淋巴管内皮细胞浆内囊泡极其丰富,数密度为118个/μm3,体密度为0.071 4;内皮细胞连接有重叠、嵌插和端端连接3种类型,处于开放状态约占21%。胞质内也含有一般的细胞器。结论在直肠内组织液和大分子物质的转运主要通过内皮细胞的连接开放和囊泡系统。

Objective To observe the fine distribution and morphologic feature of the intramural lymphatics in rats' rectum and to provide the morphological evidence for exploring the mechanism of lymphous metastasis of rectum carcinoma.Methods The intramural lymphatics of rectum in 30 rats were studied by electron microscopy.Results There are many vesicae in the endothelial of capillary lymphatics.The numerical density of lymphatics is 118/μm3,the volume density is 0.071 4.There are normal organelles in the cytoplast.The capillary lymphatics in rectums' wall have the similar ultrastructure feature to normal ones.Three kinds of endothelial cells junctions are overlapping-junctions,embedding-junctions and end-to-end-type junctions.About 21% of cell-junctions are opening types.Conclusion The results show that big molecule substance and tissue hydrolysate are transported mainly through opening-junction of endothelial cells and the vesicle system.