Presence of connective tissue proteins on the endothelium of the rat aorta.
The microdistribution of type V collagen, fibronectin, and laminin on the luminal surface of perfusion-fixed normal rat aortic endothelium has been studied by an immunoelectron microscopic method using monospecific antibodies and a protein A-gold complex. Gold particles indicating the presence of these biologically active connective tissue proteins were localized in groups on and in the vicinity of the interendothelial border. They were also found on the small flaps of cell junctions as well as on certain cell projections and scattered on the cell surface. Correlative transmission electron-microscopic examinations proved the specificity of these localizations. The endothelial cells of the aorta differed markedly in the amount of scattered connective tissue proteins on their surface, suggesting that there are several types of aortic endothelial cells with distinct functional differences. The findings provide evidence that connective tissue proteins may contribute to the surface pattern of the normal endothelium, especially on cell borders. It is likely that these proteins influence functions such as the permeability and chemotactic activity of the endothelium pertinent to the development of vascular disease.
D000818:Animals; D001011:Aorta / Q000378:metabolism*; D003094:Collagen / Q000378:metabolism*; D004727:Endothelium / Q000378:metabolism*; D005353:Fibronectins / Q000378:metabolism*; D006046:Gold; D006651:Histocytochemistry; D007158:Immunologic Techniques; D007797:Laminin / Q000378:metabolism*; D008297:Male; D008854:Microscopy, Electron; D051381:Rats; D011919:Rats, Inbred Strains; D014018:Tissue Distribution
D005353:Fibronectins; D007797:Laminin; D006046:Gold; D003094:Collagen