Developments in the study of endothelial cells by scanning electron microscopy.

This paper presents different approaches for studying arterial endothelial cells by scanning electron microscopy (SEM). These include post-fixation silver staining, Ligand-mediated osmium binding, vascular casting, autoradiography and Triton digestion. Post-fixation staining of cells with silver nitrate leads to more specific silver deposits at cell junctions and improved tissue preservation. Endothelium impregnated with osmium bound to ligand (OTO) showed enhanced membrane detail and rendered the tissue conductive. Resin casts of the microvasculature viewed by SEM showed that the endothelial surface of small vessels can now easily be viewed en face. 3H-Thymidine-labeled endothelial cells were recognized using SEM and details of the endothelial cell cytoskeleton were visualized by SEM after Triton digestion. These results demonstrate the versatility of SEM and suggest ways in which the scanning electron microscope can help to better study arterial endothelial cells.