Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0038358 (gastric ulcer)
 5,179 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Angiogenesis is an important event for gastric ulcer healing. Vascular endothelial growth factor (VEGF) is known to be a potent stimulator of angiogenesis. This study consequently examined VEGF production, VEGF mRNA expression and angiogenesis during the spontaneous and indomethacin-delayed healing of acetic acid-induced ulcers in rats. The production of VEGF, taking place in the normal mucosa, was significantly elevated by ulceration. The mRNA expression of three isoforms of VEGF (VEGF188, VEGF164 and VEGF120) was also detected. Following the increase in VEGF production, angiogenesis was significantly promoted in the ulcer base. VEGF-immunoreactivity was observed in granulocytes, fibroblasts and regenerated epithelial cells. Indomethacin markedly inhibited prostaglandin E2 synthesis in the ulcer base, resulting in the prevention of ulcer healing. Angiogenesis was also significantly inhibited by indomethacin, but neither VEGF production nor VEGF mRNA expression was reduced. Such results suggest that VEGF might play a role in angiogenesis in the spontaneous healing of gastric ulcers in rats. However, the inhibition of angiogenesis in indomethacin-delayed ulcer healing is not explainable on VEGF expression.
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PMID:Relationship between vascular endothelial growth factor and angiogenesis in spontaneous and indomethacin-delayed healing of acetic acid-induced gastric ulcers in rats. 1006 93

Endothelins (ETs) participate directly and indirectly in angiogenesis via ET receptors. During early fetal angiogenesis, vascular endothelial growth factor (VEGF) and its receptors kinase insert domain-containing receptor (KDR) and fms-like tyrosine kinase-1 (Flt-1) are required for the development of the systemic vasculature. In late angiogenesis, stromal-cell-derived factor (SDF-1) and its receptor CXC chemokine receptor 4 (CXCR4) act in an organ-specific manner to promote the formation and development of large blood vessels supplying the gastrointestinal tract. We studied the roles of these ligand receptors in angiogenesis during healing of gastric ulcers. We studied the following five groups, each consisting of ten cases of endoscopically confirmed gastric ulcer: active stage (GA), healing stage (GH) and scar stage (GS) of gastric ulcers located in the angulus; Helicobacter pylori (Hp)-positive gastritis (gast+); and Hp-negative gastritis (gast-). All cases in the ulcer groups were Hp-positive. The study materials consisted of frozen biopsy specimens of lesions arising in the angulus. ET-1 was measured by enzyme immunoassay. The other factors were assayed by reverse-transcription-PCR. The distributions of ET-1, ETA receptor (ETAR), SDF-1 and CXCR4 in the gastric mucosa were evaluated by enzyme immunoassay. ET-1 and ETAR reached peak levels during the GH (ET: P<0.05, ETAR: P<0.01). VEGF mRNA increased slightly during the GA, but did not differ significantly among the groups. KDR and Flt-1 levels were high during the GA, the level being significantly higher than those during the GH and GS (P<0.05). SDF-1 levels significantly decreased during the GH and GS compared with levels during the GA, and CXCR4 significantly increased during the GH and GS (P<0.01). On immunostaining, ET-1-positive cells and ETAR-positive cells were found in the endothelium, vascular smooth muscle and gastric epithelium, and CXCR4-positive cells were found in the endothelium and gastric epithelium during the GH and GS. Our results suggest that VEGF receptors are mainly expressed early in ulcer development and participate in the initial stage of angiogenesis. SDF-1 receptors and ETAR are primarily expressed during the GH and GS and are involved in vascular maturation and gastric mucosal regeneration during late angiogenesis.
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PMID:Roles of angiogenic factors and endothelin-1 in gastric ulcer healing. 1219 43