Analysis of delivery facilities and conditions in 1991 in mothers of infants with birth weights below 1500 grams and/or gestational age under 33 weeks

Direct sprouting (angiogenesis) does not occur during the formation of capillary-like tubes in an aorta/ collagen gel in the in vitro model. However, emigration of cells which stretch, arrange themselves side by side, form contacts (unspecific, tight and gap junctions), develop a lumen and show differentiation of endothelial cells (including the formation of a lamina densa and the appearance of pericytes) have been observed, i.e. vasculogenesis occurs. The origin of long, stretched cells is not known with certainty. They possibly represent smooth muscle cells. In addition, other cell types have been found, such as fibrocyte-like and fibroblast-like cells, elastoblasts, fat cells, monocytes and macrophages. All these cells are able to produce factors that promote the formation of new capillaries. Hence, a knowledge of these cells appears to be important for the analysis of in vitro systems. Moreover, the occurrence of these cell types must be considered when assessing possible effects.     

In vitro angiogenic and proteolytic properties of bovine lymphatic endothelial cells

The aim of the present study was to determine whether angiogenic cytokines, which induce neovascularization in the blood vascular system, might also be operative in the lymphatic system. In an assay of spontaneous in vitro angiogenesis, endothelial cells isolated from bovine lymphatic vessels retained their histotypic morphogenetic properties by forming capillary-like tubes. In a second assay, in which endothelial cells could be induced to invade a three-dimensional collagen gel within which they formed tube-like structures, lymphatic endothelial cells responded to basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) in a manner similar to what has previously been observed with endothelial cells derived from the blood vascular system. Finally, since angiogenesis is believed to require extracellular proteolytic activity, we investigated the effects of bFGF and VEGF on lymphatic endothelial cell proteolytic properties by focussing on the plasminogen activator (PA) system. bFGF and VEGF increased urokinase, urokinase receptor, and tissue-type PA expression. This was accompanied by an increase in PA inhibitor-1, which is thought to play an important permissive role in angiogenesis by protecting the extracellular matrix against excessive proteolytic degradation. Taken together, these results demonstrate that with respect to in vitro morphogenetic and proteolytic properties, lymphatic endothelial cells respond to the previously described angiogenic factors, bFGF and VEGF, in a manner very similar to what has been described for endothelial cells derived from the blood vascular system.     

Matrix metalloproteinases regulate neovascularization by acting as pericellular fibrinolysins

During angiogenesis, endothelial cells penetrate fibrin barriers via undefined proteolytic mechanisms. We demonstrate that the fibrinolytic plasminogen activator (PA)-plasminogen system is not required for this process, since tissues isolated from PA- or plasminogen-deficient mice successfully neovascularize fibrin gels. By contrast, neovessel formation, in vitro and in vivo, is dependent on fibrinolytic, endothelial cell-derived matrix metalloproteinases (MMP). MMPs directly regulate this process as invasion-incompetent cells penetrate fibrin barriers when transfected with the most potent fibrinolytic metalloproteinase identified in endothelium, membrane type-1 MMP (MT1-MMP). Membrane display of MT1-MMP is required, as invasion-incompetent cells expressing a fibrinolytically active, transmembrane-deleted form of MT1-MMP remain noninvasive. These observations identify a PA-independent fibrinolytic pathway wherein tethered MMPs function as pericellular fibrinolysins during the neovascularization process.     

Angiotensin-converting enzyme inhibitor cilazapril suppresses expression of basic fibroblast growth factor messenger ribonucleic acid and protein in endothelial and intimal smooth muscle cells in a vascular injury model of spontaneous hypertensive rats

The relationship between the expression of basic fibroblast growth factor (bFGF) messenger ribonucleic acid (mRNA) and protein, a potent mitogen for vascular smooth muscle cells in vivo, and administration of the angiotensin-converting enzyme inhibitor cilazapril, which suppresses smooth muscle cells proliferation in denuded arteries, was studied in spontaneously hypertensive rats using the in situ hybridization technique and immunohistochemical study. The effect of cilazapril on neointimal formation through modification of bFGF expression was evaluated using the increased tissue expression of the renin-angiotensin system in spontaneously hypertensive rats. Arterial injury was produced by using balloon catheter denudation in the left carotid artery of rats. The effects were evaluated 2 weeks later. bFGF mRNA and protein were observed only in the endothelial cells of sham-operated rats. bFGF mRNA and protein were observed in both endothelial cells and intimal smooth muscle cells in operated rats receiving only vehicle. Expression of bFGF mRNA and protein was suppressed in both endothelial cells and intimal smooth muscle cells of operated rats receiving cilazapril. These data suggest that cilazapril suppresses smooth muscle cell proliferation through modification of the expression of bFGF mRNA and bFGF protein in addition to other genes.     

Pericytes in the microvasculature

Pericytes, also known as Rouget cells or mural cells, are associated abluminally with all vascular capillaries and post-capillary venules. Differences in pericyte morphology and distribution among vascular beds suggest tissue-specific functions. Based on their location and their complement of muscle cytoskeletal proteins, pericytes have been proposed to play a role in the regulation of blood flow. In vitro studies demonstrating the contractile ability of pericytes support this concept. Pericytes have also been suggested to be oligopotential and have been reported to differentiate into adipocytes, osteoblasts and phagocytes. The mechanisms involved in vessel formation have yet to be elucidated but observations indicate that the primordial endothelium can recruit undifferentiated mesenchymal cells and direct their differentiation into pericytes in microvessels, and smooth muscle cells in large vessels. Communication between endothelial cells and pericytes, or their precursors, may take many forms. Soluble factors such as platelet-derived growth factor and transforming growth factors-beta are likely to be involved. In addition, physical contact mediated by cell adhesion molecules, integrins and gap junctions appear to contribute to the control of vascular growth and function. Development of culture methods has allowed some functions of pericytes to be directly examined. Co-culture of pericytes with endothelial cells leads to the activation of transforming growth factor-beta, which in turn influences the growth and differentiation of the vascular cells. Finally, the pericyte has been implicated in the development of a variety of pathologies including hypertension, multiple sclerosis, diabetic microangiopathy and tumor vascularization.     

Inhibitory effects of hypercholesterolemia and ox-LDL on angiogenesis-like endothelial growth in rabbit aortic explants. Essential role of basic fibroblast growth factor

Hypercholesterolemic (HC) rabbits exhibit suppressed compensatory vascular growth after restriction of arterial supply. However, neovascularization is commonly found in atheromas containing inflammatory cells. We used an in vitro model to determine the effects of hypercholesterolemia on angiogenesis in the absence or presence of inflammatory cells. HC rabbit aortic explants (1 mm2) with or without (n = 90 each) lesion-forming inflammatory cells were cultured in a collagen matrix with serum-free medium. Explant-derived endothelial cell growth was organized into capillary-like microtubes (CLM) that could be videomicroscopically quantified. CLM growth from lesion-free HC explants was significantly reduced to 13 +/- 4% of the value in explants (n = 90) from normocholesterolemic (NC, n = 15) rabbits (P < .001). In contrast, in lesion-containing HC explants, the matrix was invaded by foam cells, and CLM growth was not inhibited. Immunoassayable basic fibroblast growth factor (bFGF, in pg/mL) in the culture medium was significantly lower in lesion-free HC (< 5) than NC explants (11 +/- 2, P < .01) or HC explants with lesions (14 +/- 3). In addition, CLM growth was reduced in NC explants incubated with oxidized LDL (ox-LDL, 50-100 micrograms/mL). Exogenous bFGF (10 ng/mL) reversed the inhibitory effects of hypercholesterolemia and ox-LDL, whereas bFGF-neutralizing antibody (10 micrograms/mL) abolished CLM growth in all groups. In cultured rabbit aortic endothelial cells, ox-LDL reduced DNA synthesis, but this inhibition was reversed by bFGF. We conclude that hypercholesterolemia and ox-LDL inhibit angiogenesis like endothelial growth because of a suppressed availability of endogenous bFGF. Retained responsiveness to exogenous bFGF suggests that inducing bFGF expression at targeted sites may improve collateral growth in hyperlipidemic arterial disease.     

Expression and subcellular distribution of basic fibroblast growth factor are regulated during migration of endothelial cells

Migration of endothelial cells is involved in normal and pathological angiogenesis and in re-endothelialization after vascular injury or rupture of atherosclerotic plaques. Several types of endothelial cells are known to synthesize basic fibroblast growth factor (bFGF); in some of these, migration is increased by exogenous bFGF and inhibited by anti-bFGF antibodies. Using immunocytochemical techniques and RNase protection analysis, we studied endothelial cells from bovine coronary arteries and veins as well as from adrenal microvessels. We found that bFGF mRNA and peptide were present in confluent endothelial cells and were upregulated during migration stimulated by removal of some cells from the monolayer. During migration, extracellular matrix stores of bFGF were depleted, and bFGF immunoreactivity began to accumulate in the cytoplasm of endothelial cells between 2 and 6 hours. After migration had begun, but before the initiation of DNA synthesis, bFGF immunoreactivity increased in the nuclei and nucleoli. Exogenous bFGF stimulated endothelial migration, and antibodies to bFGF markedly inhibited migration, suggesting that an intracrine function of nuclear bFGF is not sufficient for cell migration. In all three types of endothelial cells studied, bFGF was identified as an endogenous regulator, but not as the sole regulator, or migration. Moreover, bFGF expression and subcellular localization were found to be regulated during endothelial cell migration.     

Adverse effects associated with influenza vaccine in pediatrics

To investigate mechanisms of capillary network remodeling, we developed a serum-free angiogenesis in vitro system in three-dimensional fibrin matrices which allows the study of directional growth of endothelial sprouts, anastomosis, and remodeling ('pruning') of the primitive plexus toward more elaborated capillary trees. To follow the movements of living endothelial cells by inverse-fluorescence microscopy, we cocultured unlabeled endothelial cells with endothelial cells labeled with the carbocyanine dye 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI). We show that elongation and retraction of neighboring capillary sprouts occurs simultaneously, resembling a tug-of-war by which endothelial cells are withdrawn from shortening sprouts to become incorporated in other sprouts nearby. For the first time, we directly demonstrate the long-suspected parallel sliding movement of endothelial cells. We show that cell migration persists within immature capillaries even after sprouts have merged to continuous capillary loops, leading to overlapping growth of opposing sprout tips. As a novel concept of capillary remodeling, we distinguish two types of endothelial cell migration: sprouting and guided migration. Sprouting is the de novo invasion of a matrix by endothelial cells, and guided migration is the locomotion of cells along preexistent capillary-like structures. We show that guided migration leads to remodeling of immature capillary networks and to the retraction of sprouts. We describe a method for quantification of sprouting versus guided migration in DiI-mosaic-labeled capillary networks, and we present evidence that endothelial cell-derived basic fibroblast growth factor serves as a chemotactic signal for other cells to migrate along a preestablished capillary-like structure.     

Distribution of galanin-like immunoreactive elements in the brain of the adult lamprey Lampetra fluviatilis

The formation of microvascular sprouts during angiogenesis requires that endothelial cells move through an extracellular matrix. Endothelial cells that migrate in vitro generate forces of traction that compress (i.e., contract) and reorganize vicinial extracellular matrix, a process that might be important for angiogenic invasion and morphogenesis in vivo. To study potential relationships between traction and angiogenesis, we have measured the contraction of fibrillar type I collagen gels by endothelial cells in vitro. We found that the capacity of bovine aortic endothelial (BAE) cells to remodel type I collagen was similar to that of human dermal fibroblasts--a cell type that generates high levels of traction. Contraction of collagen by BAE cells was stimulated by fetal bovine serum, human plasma-derived serum, bovine serum albumin, and the angiogenic factors phorbol myristate acetate and basic fibroblast growth factor (bFGF). In contrast, fibronectin and immunoglobulin from bovine serum, several nonserum proteins, and polyvinyl pyrrolidone (a nonproteinaceous substitute for albumin in artificial plasma) were not stimulatory. Contraction of collagen by BAE cells was diminished by an inhibitor of metalloproteinases (1,10-phenanthroline) at concentrations that were not obviously cytotoxic. Zymography of proteins secreted by BAE cells that had contracted collagen gels revealed matrix metalloproteinase 2. Subconfluent BAE cells that were migratory and proliferating were more effective contractors of collagen than were quiescent, confluent cells of the same strain. Moreover, bovine capillary endothelial cells contracted collagen gels to a greater degree than was seen with BAE cells. Collectively, our observations indicate that traction-driven reorganization of fibrillar type I collagen by endothelial cells is sensitive to different mediators, some of which, e.g., bFGF, are known regulators of angiogenesis in vivo.     

Dual pathways of tubular morphogenesis of vascular endothelial cells by human glioma cells: vascular endothelial growth factor/basic fibroblast growth factor and interleukin-8

In this study, we examined whether human glioma cells are angiogenic in a model using human microvascular endothelial cells, and also which factor is responsible for the glioma-dependent angiogenesis. Tubular morphogenesis in type I collagen gel by human microvascular endothelial cells was stimulated in the presence of 10 and 100 ng/ml of vascular endothelial growth factor (VEGF), 10 ng/ml basic fibroblast growth factor (bFGF) and 10 ng/ml of interleukin-8 (IL-8). Tube formation of the microvascular endothelial cells was assayed in the glioma cell lines IN157 and IN301, co-cultured using the double chamber method. IN301 cells had much higher levels of VEGF, bFGF and transforming growth factor-beta mRNA than IN157 cells, whereas the two had similar levels of transforming growth factor-alpha mRNA. By contrast, IN157 cells had much higher levels of IL-8 mRNA than IN301 cells. IN301-dependent tubular morphogenesis was inhibited by anti-VEGF or anti-bFGF antibody, and the inhibition was almost complete when anti-VEGF and anti-bFGF antibodies were present. On the other hand, IN157-dependent tubular morphogenesis was inhibited by anti-IL-8 antibody, but not by anti-VEGF or anti-bFGF antibodies. These findings demonstrated dual paracrine controls of tumor angiogenesis by human glioma cells. One is mediated through VEGF and/or bFGF, and the other, through IL-8.     

The configuration of fibrin clots determines capillary morphogenesis and endothelial cell migration

In the living organism, capillary growth frequently occurs in a fibrin-rich extracellular matrix. The structure and the mechanical properties of fibrin clots are influenced by various macromolecules (i.e., hyaluronic acid and thrombospondin) and also by pH, ionic strength, and thrombin concentrations of the milieu in which they polymerize. The configuration (three-dimensional architecture) and the rigidity of fibrin clots correlate with their opacity measured by spectrophotometric absorbance readings at 350 nm. By using bovine pulmonary artery endothelial cells and bovine fibrinogen, we show here that transparent fibrin clots (A(350) < 1.0), polymerized at > or = pH 7.5 or in the presence of increased thrombin or sodium chloride concentrations, strongly stimulated capillary morphogenesis in vitro. In contrast, opaque fibrin gels (A(350) > 1.5), polymerized at pH 7.2 or in the presence of dextran, stimulated only the migration of endothelial cells but not capillary morphogenesis. We demonstrate that the angiomorphogenic effects of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) are strongly dependent on the structure of the fibrin clots. Our findings suggest that bFGF/VEGF primarily stimulate the proliferation of endothelial cells, whereas the three-dimensional architecture of the fibrin matrix is decisive for capillary morphogenesis.     

Expression of the angiogenic factors, basic fibroblast growth factor and vascular endothelial growth factor, in the ovary

In adult tissues, vascular growth (angiogenesis) occurs normally during tissue repair, such as in the healing of wounds and fractures. Inappropriate vascular growth is associated with various pathological conditions. These conditions include tumor growth, retinopathies, hemangiomas, fibroses, and rheumatoid arthritis in the case of rampant vascular growth and nonhealing wounds and fractures in the case of inadequate vascular growth. The female reproductive organs exhibit dramatic, periodic growth and regression, accompanied by equally dramatic changes in their rates of blood flow. Thus, it is not surprising that they are some of the few adult tissues in which angiogenesis occurs as a normal process. Ovarian follicles and corpora lutea contain and produce angiogenic factors. These angiogenic factors bind heparin and seem to belong to the fibroblast growth factor (FGF) and vascular endothelial growth factor (VEGF) families of proteins. Based on our studies of the pattern of expression of FGF and its major receptors in bovine, ovine, and porcine corpora lutea, we have suggested that FGF may influence not only luteal cell proliferation but also cell death, thereby regulating cell turnover in the luteal vascular and nonvascular compartments. In addition, we recently have shown that luteal expression of VEGF is greatest during the early luteal phase, coincident with luteal vascularization. Moreover, VEGF is present exclusively in luteal connective tissue and perivascular (arteriolar smooth muscle and capillary pericyte) cells. In fact, the first thecal-derived cells to invade the granulosa-derived regions immediately after ovulation seem to be VEGF-containing pericytes. We have therefore hypothesized that ovarian pericytes play a key role in vascularization of developing follicles and corpora lutea. Further understanding of the specific physiological roles of these factors in follicular and luteal growth, development, and function will ultimately lead to improved methods of regulating fertility.     

Fibroblast growth factor-2 (FGF-2) induces vascular endothelial growth factor (VEGF) expression in the endothelial cells of forming capillaries: an autocrine mechanism contributing to angiogenesis

FGF-2 and VEGF are potent angiogenesis inducers in vivo and in vitro. Here we show that FGF-2 induces VEGF expression in vascular endothelial cells through autocrine and paracrine mechanisms. Addition of recombinant FGF-2 to cultured endothelial cells or upregulation of endogenous FGF-2 results in increased VEGF expression. Neutralizing monoclonal antibody to VEGF inhibits FGF-2-induced endothelial cell proliferation. Endogenous 18-kD FGF-2 production upregulates VEGF expression through extracellular interaction with cell membrane receptors; high-Mr FGF-2 (22-24-kD) acts via intracellular mechanism(s). During angiogenesis induced by FGF-2 in the mouse cornea, the endothelial cells of forming capillaries express VEGF mRNA and protein. Systemic administration of neutralizing VEGF antibody dramatically reduces FGF-2-induced angiogenesis. Because occasional fibroblasts or other cell types present in the corneal stroma show no significant expression of VEGF mRNA, these findings demonstrate that endothelial cell-derived VEGF is an important autocrine mediator of FGF-2-induced angiogenesis. Thus, angiogenesis in vivo can be modulated by a novel mechanism that involves the autocrine action of vascular endothelial cell-derived FGF-2 and VEGF.     

First-incidence anxiety in the Lundby Study: course and predictors of outcome

PURPOSE: In this study, we investigated the ultrastructure of the microvasculature in human renal cell carcinoma (RCC) specimens. MATERIALS AND METHODS: RCC specimens from 30 patients were studied by light microscopy after hematoxylin and eosin staining and alpha-smooth muscle actin staining, and by electron microscopy after uranyl acetate lead nitrate staining or periodic acid thiosemicarbazide gelatin methenamine silver staining. RESULTS: In the light microscopy, the capillaries located adjacent to the renal medullary tubules in normal renal tissue specimen were in an orderly manner, while capillaries in the RCC specimens were found to be densely or sparsely distributed unconventionally. The pericytes encircling the capillary endothelial cells were positive for alpha-smooth muscle actin and formed aggregates in many of the RCC specimens, but did not form aggregates in the normal tissue specimens. In the electron microscopy, capillary endothelial cells in the normal renal tissue specimens were found to form well-developed membranous structure such as characterized by fenestrations and tight junctions. However, few pericytes were detected. On the other hand, the capillary endothelial cells in RCC specimens were found to be immature with poorly developed junctional complexes. Capillary pericytes with numerous cytoplasmic processes were found in many of the RCC specimens. In addition, the basement membranes of the capillary walls were structurally abnormal in that it was being multilayered. Based on the results of analysis of a total of 324 capillaries observed in all RCC specimens, capillaries could be classified as type I capillaries, associated with well-developed pericytes with numerous processes, or type II capillaries, associated with few pericytes with few processes. Type I capillaries predominated in cases which an angiographically hypervascularity was detected. Whereas, type II capillaries predominated in cases in which angiographically hypovascular pattern were detected. CONCLUSION: The fine structure of the pericytes seems to reflect the qualitative difference in capillary structure between normal renal tissue and RCC specimens. Therefore, the present findings may contribute to the recognition of intratumoral hemodynamics.     

Overexpression of VEGF in testis and epididymis causes infertility in transgenic mice: evidence for nonendothelial targets for VEGF

Vascular endothelial growth factor (VEGF) is a key regulator of endothelial growth and permeability. However, VEGF may also target nonendothelial cells, as VEGF receptors and responsiveness have been detected for example in monocytes, and high concentrations of VEGF have been reported in human semen. In this work we present evidence that overexpression of VEGF in the testis and epididymis of transgenic mice under the mouse mammary tumor virus (MMTV) LTR promoter causes infertility. The testes of the transgenic mice exhibited spermatogenic arrest and increased capillary density. The ductus epididymidis was dilated, containing areas of epithelial hyperplasia. The number of subepithelial capillaries in the epididymis was also increased and these vessels were highly permeable as judged by the detection of extravasated fibrinogen products. Intriguingly, the expression of VEGF receptor-1 (VEGFR-1) was detected in certain spermatogenic cells in addition to vascular endothelium, and both VEGFR-1 and VEGFR-2 were also found in the Leydig cells of the testis. The infertility of the MMTV-VEGF male mice could thus result from VEGF acting on both endothelial and nonendothelial cells of the male genital tract. Taken together, these findings suggest that the VEGF transgene has nonendothelial target cells in the testis and that VEGF may regulate male fertility.     

Omega-3 polyunsaturated fatty acid levels in the diet and in red blood cell membranes of depressed patients

The objective of this study was to clarify the possible angiogenesis-promoting factors from human trophoblasts in early stage gestation. The existence of angiogenic growth factors such as basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) in the condition medium from human villous trophoblasts was determined. Biological activity of angiogenic growth factors released by trophoblasts was examined using vascular endothelial cell lines. The condition medium from trophoblasts enhanced the growth of endothelial cells. Although cultured trophoblasts exhibited immunoreactive products for both bFGF and VEGF in the cytoplasm, only bFGF was detected in the condition medium by ELISA. The growth-enhancing activity of the condition medium was eliminated completely by the addition of anti-bFGF antibody but not with anti-VEGF antibody. Thus, trophoblastic cells seem to play an important role in extensive angiogenesis occurring in early gestation, mainly by releasing bFGF but not VEGF.     

Molecular regulation of UVB-induced cutaneous angiogenesis

We determined whether cutaneous angiogenesis induced by exposure of mice to ultraviolet-B (UVB) radiation is associated with an imbalance between positive and negative angiogenesis-regulating molecules. Unshaved C3H/HeN mice were exposed to a single dose (15 kJ per m2) of UVB. At various times, the mice were killed, and their external ears were processed for routine histology and immunohistochemistry. Antibodies against proliferating cell nuclear antigen and bromodeoxyuridine identified dividing cells. Antibodies against CD31/ PECAM-1 identified endothelial cells, and antibodies against basic fibroblast growth factor (bFGF), vascular endothelial growth factor/vascular permeability factor, and interferon-beta (IFN-beta) identified angiogenesis-regulating molecules. Epidermal hyperplasia was documented by 48 h and reached a maximum on day 7 after exposure to UVB. The expression of bFGF increased by 24 h, whereas the expression of IFN-beta decreased by 72 h after exposure to UVB. The expression of vascular endothelial growth factor/vascular permeability factor increased slightly after irradiation. The altered balance between bFGF and IFN-beta was associated with increased endothelial cell proliferation (bromodeoxyuridine + CD31 + cells) within existing blood vessels, leading to telangiectasia and new blood vessels. UV-induced epidermal hyperplasia and cutaneous angiogenesis were highest in IFN-alpha/beta receptor knockout mice. These results demonstrate that in response to UVB radiation, dividing keratinocytes produce a positive angiogenic molecule (bFGF) but not a negative angiogenic molecule (IFN-beta), and that this altered balance is associated with enhanced cutaneous angiogenesis.     

The role of NF-kappaB in the angiogenic response of coronary microvessel endothelial cells

The activation of nuclear factor (NF)-kappaB by 12(R)-hydroxyeicosatrienoic acid [12(R)-HETrE], an arachidonic acid metabolite with potent stereospecific proinflammatory and angiogenic properties, was examined and its role in the angiogenic response was determined in capillary endothelial cells derived from coronary microvessels. Electrophoretic mobility-shift assay of nuclear protein extracts from cells treated with 12(R)-HETrE demonstrated a rapid and stereospecific time- and concentration-dependent increase in the binding activity of NF-kappaB, which was inhibitable by the antioxidants N-acetylcysteine, butylated hydroxyanisole, and pyrrolidine dithiocarbamate and was partially attenuated by the protein kinase C inhibitors, staurosporine and calphostin C. Neither 12(S)-HETrE nor other related eicosanoids--e.g., 12(R)-HETE, 12(S)-HETE, and leukotriene B4--stimulated the activation of NF-kappaB relative to 12(R)-HETrE, substantiating the claim for a specific receptor-mediated mechanism. 12(R)-HETrE stimulated the formation of capillary-like cords of microvessel endothelial cells distinguishable from a control; this effect was comparable to that observed with basic fibroblast growth factor (bFGF). Inhibition of NF-kappaB activation resulted in inhibition of capillary-like formation of endothelial cells treated with 12(R)-HETrE by 80% but did not affect growth observed with bFGF. It is suggested that 12(R)-HETrE's angiogenic activity involves the activation of NF-kappaB, possibly via protein kinase C stimulation and the generation of reactive oxygen intermediates for downstream signaling.     

Study of the repairing process of gastric ulcer using multivariate analysis of bFGF-positive cells, haemodynamics, PAS-positive mucus amount and glandular index in the gastric mucosa

To investigate pathophysiological diversities in the repairing process of gastric ulcer, distribution density of basic fibroblast growth factor (bFGF)-positive fibroblasts and myofibroblasts and vascular endothelial cells, mucosal haemoglobin content, PAS-positive mucus amount and glandular index were compared in the peripheral region of an open ulcer (the unhealed group; n = 17), the central region of a red scar (the red scar group; n = 32) and the central region of the white scar (white scar group; n = 32). Density of bFGF-positive fibroblasts and myofibroblasts and vascular endothelial cells was highest in the unhealed group, followed by the red scar group, while the white scar group showed a low value close to control. Mucosal haemoglobin content was high in the red scar and unhealed groups. PAS-positive mucus amount in the unhealed and red scar groups showed lower values compared with that in the white scar group. Glandular index in the unhealed group was the lowest, followed by the red scar group, while the white scar group neared control values. Statistically significant correlations were observed between the density of bFGF-positive "fibroblasts and myofibroblasts' and density of bFGF-positive vascular endothelial cells, between the density of bFGF-positive vascular endothelial cells and mucosal haemoglobin content and between the PAS-positive mucus amount and glandular index. Discriminant analysis demonstrated that the unhealed group could be distinguished from the red and white scar groups, based on glandular index, density of bFGF-positive "fibroblasts and myofibroblasts', mucosal haemoglobin content and PAS-positive mucus amount, while the red scar group could be discriminated from the white scar group based on the density of bFGF-positive "fibroblasts and myofibroblasts', density of bFGF-positive vascular endothelial cells, glandular index, haemoglobin content and PAS-positive mucus amount. The white scar group was difficult to discriminate from control. Our present results show that the recovery of glandular formation and mucus production continues throughout the repairing process, whereas the acceleration of angiogenesis and granulation formation is observed only in unhealed ulcers and at the red scar stage.