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Showing papers on "Vascular endothelial growth factor A published in 1982"


Journal ArticleDOI
TL;DR: The conditioned medium of confluent endothelial cells contains factors that inhibit the growth of actively dividing endothelial and smooth muscle cells, and it is speculated that this inhibitory activity plays an important role in the regulation of smooth muscle cell proliferation.

139 citations


Journal ArticleDOI
TL;DR: Results indicate that PDGF is the primary factor in serum responsible for the migration of cultured aortic smooth muscle cells and that PF4 is a critical factor required to induce the Migration of pericytes.
Abstract: Phagokinetic migration of cultured vascular cells was tested in response to human platelet-rich serum ('serum') and human platelet-poor plasma serum ('plasma'). The cell types tested included bovine aortic endothelial cells, human umbilical vein endothelial cells, human haemangiomal capillary endothelial cells, bovine adrenal microvascular pericytes, and bovine aortic smooth muscle cells. Human serum stimulated a significant increase in the rate of migration for all five cell types. Human plasma stimulated the endothelial cells to migrate but had no effect on the migration of pericytes or smooth muscle cells. Highly purified platelet-derived growth factor (PDGF) stimulated dose-dependent migration of smooth muscle cells causing a 50% increase in phagokinetic track area relative to controls. Neither pericyte nor endothelial cell migration was stimulated by PDGF. Rabbit antiserum to human PDGF completely blocked the smooth muscle cell migration induced by either 10% serum or 1 ng/ml pure PDGF. Purified platelet factor IV (PF4) stimulated migration of pericytes but not of smooth muscle cells nor endothelial cells. Sheep antiserum to human PF4 completely blocked the pericyte migration induced by either 10% serum or 1 microgram/ml pure PF4. These results indicate that PDGF is the primary factor in serum responsible for the migration of cultured aortic smooth muscle cells and that PF4 is a critical factor required to induce the migration of pericytes. Other factors present in both plasma and serum control the migration of vascular endothelial cells.

84 citations


Journal ArticleDOI
TL;DR: The disorderly growth and the abnormal production of type I collagen by these vascular endothelial cells cultured in the absence of fibroblast growth factor is a model for a number of pathological situations including atherosclerotic plaque formation.
Abstract: Vascular endothelial cells derived from adult bovine aortic arch can be grown in two ways, either in the presence or absence of fibroblast growth factor. The types of collagen produced by cultures under these two con- ditions have been compared. In the presence of fibroblast growth factor, cells grow in an orderly fashion, express their normal phenotype and synthesize primarily type III collagen plus collagens types IV and V at a ratio of 10: 1: 3. Cultures grown in the absence of the factor lose their orderly pattern of growth, lose polarity and normal phenotypic expression. They devote twice the proportion of total protein-synthesizing capacity to collagen, and now synthesize type I in addition to the other collagen types. The ratio of collagen types I: III: IV: V is approxi- mately 30:70:1:13. The kinds of type V collagen chains expressed are also altered. Fibroblast growth factor appears to modulate collagen synthesis, the major component of the extracellular matrix, and indirectly modulates the phenotypic expression of cultured vascular endothelial cells. In atherosclerosis, type I collagen is found in association with the intimal layer. The disorderly growth and the abnormal production of type I collagen by these vascular endothelial cells cultured in the absence of fibroblast growth factor is a model for a number of pathological situations including atherosclerotic plaque formation.

48 citations


Journal ArticleDOI
TL;DR: An inverse correlation between stress-fiber density and cell motility is demonstrated and is conclusively demonstrated.
Abstract: Although it is generally accepted that cytoplasmic actomyosin interactions generate force for cellular and subcellular movements, the nature of the tensionproducing mechanism has not been revealed.'-3 To reach this goal, biochemists must learn what milieu regulates the assembly and dismantling of the motor,4 while molecular anatomists must reveal the precise form and arrangement of the component parts and the manner in which they are anchored within cells and tissues to produce functional motility in vivo. In addition to their presumed role in cell motility, the biophysical properties of cytoplasmic actomyosin and the associated proteins,1,2,4,5 contribute to the maintenance of cytoplasmic structure during motility and quiescence. Light microscopic studies using time-lapse videotapes to document cell movements prior to the localization of the contractile proteins with specific markers indicate that when actomyosin is involved in structural support of the cytoplasm its form and distribution differ from those seen during cell movements.6 Fast-moving cells display a diffuse or randomized distribution of contractile proteins (FIGURE 1)and slow-moving cells possess combinations of diffuse and fibrous straining patterns (FIGURE 2). By contrast, immobilized cells possess mostly fibrous staining for actin and myosin (FIGURE 3). These results conclusively demonstrate an inverse correlation between stress-fiber density and cell motility.6 Thus, although it has been demonstrated that stress fibers possess an assortment of contractile proteins as well as contractile potential in model systems in uitro,7.8 it is unlikely they are important for moving cells in vivo.6 What role do stress fibers play in uivo? Until this time, little was known regarding the existence and function of these bundles of contractile proteins. Only in the vascular endothelium had bundles of 6-7 nm (actin) filaments been ob~erved,~ but it was not known whether they also contained the other contractile proteins localized to stress fibers of cultured cells (e.g. myosin and cr-actinin).lo We searched in tissues for cells with a microfilamentous bundle system comparable to the stress fibers of immobilized cells grown in tissue culture,

47 citations


Journal ArticleDOI
TL;DR: The results indicated that endothelial cell migration in vitro is not dependent on plasminogen, which may be another unique property of endothelial cells.

34 citations


Journal ArticleDOI
TL;DR: 35S-Labeled oligosaccharides, isolated as glycopeptides, were resistant to a variety of chemical and enzymatic treatments which degraded vascular cell sulfated glycosaminoglycans but appear to contain terminal sialic acid residues.
Abstract: Cultured vascular endothelial cells incorporate 35SO4 into a class of oligosaccharides which are N-glycosidically linked to cell-surface or extracellular proteins. This type of sulfated oligosaccharide was not synthesized by smooth muscle cell cultures and may represent sulfation of vascular tissue glycoproteins which are unique to endothelial cells. These endothelial cell 35S-labeled oligosaccharides are not released from the polypeptides under alkaline conditions that cleave O-glycosidically linked chains. The incorporation of both [3H]hexosamine and 35SO4 into these oligosaccharides is inhibited by tunicamycin, an antibiotic which inhibits protein N-glycosylation. 35S-Labeled oligosaccharides, isolated as glycopeptides, were resistant to a variety of chemical and enzymatic treatments which degraded vascular cell sulfated glycosaminoglycans but appear to contain terminal sialic acid residues. Endothelial cell sulfated oligosaccharide chains could also be distinguished from sulfated glycosaminoglycans by the apparent size and charge. Endothelial cells released or secreted 35S-labeled glycoproteins into the culture medium. These soluble 35S-labeled glycoproteins were partially purified by DEAE-cellulose chromatography and separated from the 35S-labeled proteoglycans, which are also released into the medium. The major 35S-labeled glycoproteins released from the cells had apparent molecular weights of 24 000--66 000. The cell-associated 35S-labeled glycoproteins, released with ethylenediaminetetraacetate or extracted with 0.5% octyl glucoside, were partially purified on DEAE-cellulose and had apparent molecular weights of 45 000--250 000.

32 citations


Journal ArticleDOI
TL;DR: Biological active, electron-opaque conjugates of histamine and its agonists are produced, which are recently used to localize in situ the histamine receptors on the vascular endothelium.
Abstract: The physiological activities of histamine on various systems including the heart and blood vessels'-9 are mediated by at least two different types of receptors.10-12 As defined on a pharmacological basis, the H1 receptors are specifically inhibited by classical antihistamines such as mepyramine, and have as agonists drugs such as 2-pyridylethylamine, The Hz receptors are blocked by antagonists such as cimetidine, and have as a specific agonist 4-methylhistamine.4~~~~~~~~~~~4 The identification of histamine receptors and their subclasses on diverse cells, including those of the cardiovascular system, has relied primarily on the target responses to histamine and its specific agonists and antagonists.15-26 It has been demonstrated that histamine receptors are located on the plasma membrane of several mammalian cells.27-33 Their presence was so far detected either indirectly, by the binding of various cells to histamine insolubilized on agarose beads,z7.34.35 or visualized at the light microscope level by coupling histamine to bovine serum albumin-fluoresceine isothiocyanatezz or to o-phthaldialdehyde.36 Another indirect way of identifying histamine receptors was by measuring the binding of the antagonist [3H]mepyramine.37 However, the direct detection and the topographical distribution of histamine receptors and their subclasses at the ultrastructural level have not been accomplished yet. We have carried out studies with the electron microscope to localize histamine receptors in various cells of the vessel wall. For this purpose, we have produced biologically active, electron-opaque conjugates of histamine and its agonists, which we have recently used to localize in situ the histamine receptors on the vascular endothelium.38-40

32 citations



Journal ArticleDOI
Robert S. Bar1
TL;DR: This report summarizes the data supporting the data supported by specific receptors for insulin and one of the insulin-like growth factors, multiplication stimulating activity (MSA), in cultured human and bovine endothelial cells.
Abstract: Recent studies have identified specific receptors for insulin and one of the insulin-like growth factors, multiplication stimulating activity (MSA), in cultured human and bovine endothelial cells. For insulin, specific receptors have also been demonstrated in intact vascular endothelium. This report summarizes the data supporting these conclusions. The manuscript is divided into three sections: (1) data obtained in cultured endothelial cells, (2) observations in intact endothelium, and (3) potential significance of receptors for insulin and insulin-like growth factors.

15 citations