title: Scanning electron microscopy examination of endothelium morphology in human carotid plaques.
abstract: In recent years, experimental and clinical evidence has been provided regarding endothelial dysfunction and its contribution to the inflammatory process leading to atherosclerotic plaque formation. All the techniques employed direct to the study of endothelial dysfunction, however usually require isolation of endothelial cells and therefore tissue manipulation and destruction, with subsequent loss of information regarding morphology and topographical distribution of the lesions. By means of scanning electron microscopy (SEM), we have investigated the characteristics of the endothelial layer in carotid specimens obtained from subjects undergoing carotid endarterectomy. Carotid specimens obtained from 6 patients undergoing carotid endarterectomy for stenosis> or =70% were fixed, prepared and examined by use of SEM in a direct mode. All the plaque specimens showed increased thickness of subendothelial connective tissue with respect to post-mortem tissue obtained from an healthy subject. Endothelial layers were typically detached from the basal lamina surface and infiltrating cells (mainly erythrocytes and, possibly, monocytes) could be identified. Endothelial cells in proximity of the plaques had irregular shape, with prominent nuclei. In several areas, the endothelial layer was completely absent and basal lamina completely uncovered. In the present study, by using SEM analysis, the morphological features of dysfunctional endothelium in human carotid plaques were extensively documented at the ultrastructural level. SEM is a powerful investigational technique which allows tridimensional examination of specimens without disruption of the originary morphology.
authors.affiliation: Department of Human Morphology, University of Insubria, Varese, Italy.
authors.forename: Terenzio
authors.initials: T
authors.lastname: Congiu
authors.forename: Laura
authors.initials: L
authors.lastname: Schembri
authors.forename: Matteo
authors.initials: M
authors.lastname: Tozzi
authors.forename: Luigina
authors.initials: L
authors.lastname: Guasti
authors.forename: Ramona Consuelo
authors.initials: RC
authors.lastname: Maio
authors.forename: Marco
authors.initials: M
authors.lastname: Cosentino
authors.forename: Franca
authors.initials: F
authors.lastname: Marino
mesh_terms: D000368:Aged; D016893:Carotid Stenosis / Q000473:pathology* / Q000601:surgery; D004727:Endothelium / Q000473:pathology* / Q000648:ultrastructure; D005260:Female; D006801:Humans; D008297:Male; D008855:Microscopy, Electron, Scanning; D008875:Middle Aged