标记脂肪进入中央乳糜管途径的电镜观察

目的：追踪观察染料颗粒由肠腔进入中央乳糜管的途径，证明肠壁内淋巴管前通路的存在。方法：用苏丹黑B标记的脂肪喂食大鼠。光、电镜下观察不同时间内，小肠各段颗粒出现的部位。结果：(1)上皮细胞内及其间的组织液池内充满染料颗粒。(2)染料颗粒经上皮细胞间的组织液池开口穿过基膜裂隙进入固有层的组织液池。(3)组织液池无内皮细胞形成的壁。(4)中央乳糜管的内皮细胞胞浆内充满染料颗粒，部分颗粒见于小泡内或内皮细胞的连接处。结论：(1)从上皮细胞的组织液池至中央乳糜管前的途径可视为小肠的淋巴管前通路。(2)脂肪进入中央乳糜管是通过空泡转运或内皮细胞连接处。

Electron microscope observation of pathway by which fat entering into lacteal

Objective:To prove the existence of prelymphatic pathway by following the trail of pellets from the intestinal lumen to the lacteals. Methods: Sudan Black B was used to label fat to feed rats. Different parts of intestine were obtained respectively at different time points. The light and electron microscope were used to observe the location of pellets and confirm the pathway which the macromolecular substances went into the lymphatics. Results: (1)The dye pellets were filled in the epithelial and tissue fluid pool between the epithelia. (2)There were orifices passing the base membrane fissures in tissue fluid pool,by this the dye pellets entered the tissue fluid pool of the lamina propia. (3)The walls of the tissue fluid pool were not endothelia. (4)The dye pellets existed in endothelial plasma of the lacteals. Part of pellets were found not only in vesicles,but also around interendothelial junctions. Conclusion: (1) prelymphatic pathway may be the route from tissue fluid pool between the epithelial cells to lacteal in intestine. (2) The path by which fat get into lacteals may be transmited by the vesicles of endothelium, or by the interendothelial junctions.