Endothelial stomatal and fenestral diaphragms in normal vessels and angiogenesis

• Published in: Journal of cellular and molecular medicine Vol. 11; no. 4; pp. 621 - 643
• Main Author: Stan, R.V.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.07.2007; John Wiley & Sons, Inc
• Subjects: Angiogenesis; Animals; Blood vessels; Cardiovascular system; Caveolae; Cell culture; Cell differentiation; Cells; Diaphragm - blood supply; Diaphragm - cytology; Diaphragm - ultrastructure; Diglycerides; Electron microscopes; Endothelium; Endothelium, Vascular - cytology; Endothelium, Vascular - ultrastructure; Esters; fenestrae; Fibroblasts; Gene expression; Growth factors; Humans; lipid rafts; Localization; Microvasculature; Models, Biological; mRNA; Neovascularization, Pathologic; Neovascularization, Physiologic; Ontogeny; Organelles; Permeability; Phenotypes; Phorbol esters; Plasma; Plasma membranes; Proteins; PV1, PLVAP; Reviews; Stomata; Structure-function relationships; transendothelial channels; Transmission electron microscopy; Vascular endothelial growth factor; vascular permeability; Vascularization
• ISSN: 1582-1838; 1582-4934
• DOI: 10.1111/j.1582-4934.2007.00075.x

•  Introduction •  Endothelial phenotypes—morphology •  Structure of endothelial stomatal and fenestral diaphragms in normal endothelium ‐  Caveolae and their stomatal diaphragms ‐  Endothelial fenestrae ‐  Transendothelial channels ‐  Vesiculo‐vacuolar organelles (VVO) ‐  Endothelial pockets •  Structures present in the endothelium in neovascularization ‐  Vasculogenesis and angiogenesis in the embryo ‐  Arteriogenesis ‐  Angiogenesis in the adult ‐  Pathologic angiogenesis •  Components of the stomatal and fenestral diaphragms ‐  Plasmalemma vesicle associated protein (gp68, PV‐1, PV1) ‐  Gene features and expression of mRNA ‐  Protein features and properties ‐  Localization ‐  PV1 is necessary and sufficient to form fenestral diaphragms and stomatal diaphragms ‐  Other components •  Working model of pv1 integration in the structure of the diaphragms •  PV1 and the endothelial diaphragms in ontogeny •  Regulation of endothelial specific structures ‐  PV1 and diaphragms are lost upon EC dedifferentiation in cell culture ‐  The endothelial diaphragms are inducible structures ‐  Matrix components ‐  Phorbol esters/diacylglycerol ‐  Growth factors—the role of VEGF ‐  Other angiogenic factors that induce diaphragms •  Function of endothelial diaphragms in normal vessels and angiogenesis •  Conclusions Vascular endothelium lines the entire cardiovascular system where performs a series of vital functions including the control of microvascular permeability, coagulation inflammation, vascular tone as well as the formation of new vessels via vasculogenesis and angiogenesis in normal and disease states. Normal endothelium consists of heterogeneous populations of cells differentiated according to the vascular bed and segment of the vascular tree where they occur. One of the cardinal features is the expression of specific subcellular structures such as plas‐malemmal vesicles or caveolae, transendothelial channels, vesiculo‐vacuolar organelles, endothelial pockets and fenestrae, whose presence define several endothelial morphological types. A less explored observation is the differential expression of such structures in diverse settings of angiogenesis. This review will focus on the latest developments on the components, structure and function of these specific endothelial structures in normal endothelium as well as in diverse settings of angiogenesis.