title: High-voltage electron microscopy of capillary endothelial vesicles.
abstract: Conventional electron microscopy of thin sections through capillary walls is inadequate to discern the relationships between endothelial vesicles and their association with the cell surface. High-voltage electron microscopy of thick sections through diaphragm muscle capillaries has been employed to visualize the three-dimensional structure of the vesicular system. Stereopairs of thick sections provide for direct three-dimensional observations of samples several vesicle diameters deep. A variety of simple and compound vesicular forms are present but not all are conjoined or maintain connections with the endothelial cell surface. This contributes to the concept of a dynamic interaction between free and attached vesicular structures where fission and fusion events compartmentalize and reconnect repeatedly. Such interactions would provide for a discontinuous pathway across the capillary wall but with a higher degree of complexity than a simple shuttling mechanism.
mesh_terms: D000818:Animals; D001485:Basement Membrane / Q000648:ultrastructure; D002196:Capillaries / Q000648:ultrastructure*; D003964:Diaphragm / Q000098:blood supply; D004727:Endothelium / Q000648:ultrastructure; D047348:Hydrolyzable Tannins; D008854:Microscopy, Electron / Q000379:methods*; D010780:Photogrammetry; D051381:Rats
chemical_list: D047348:Hydrolyzable Tannins