The organization of endocytotic vesicles in lymphatic endothelium

摘要: Abstract The lymphatic endothelium from renal hilar lymphatics in the rat was subjected to qualitative and quantitative ultrastructural analysis with emphasis on extent disposition of its vesicular component. uncoated endocytotic vesicles had an average maximum diameter 0.073 μm occupied 7% cytoplasm. There were approximately 21 each cubic micrometer In standard electron microscopic preparations glutaraldehyde-fixed 50% appeared lie free within remainder seen touch or open onto luminal abluminal surface endothelium. degree which intracytoplasmic remained discrete communicated plasma membrane examined using tannic acid ruthenium red. These substances specifically bind charged molecules cell identify membranes continuous it. When this technique applied aldehyde-fixed tissue nearly 90% that apparently could be shown retain a connection surface, equal numbers communicating either surface. At least 15% these existed as intercommunicating clusters. results suggest many are not simple units, but rather form parts chains reach Thus, may cut cross section. possible relation between chemical fixation plan organization is discussed it concluded while result overestimation vesicles, aspects vesicle seem largely unaffected. Although functional significance our observations has yet determined, should apply initial well, concept transport solely by random movement across modified.