neuropeptide-y has been researched along with Gastrointestinal-Hemorrhage* in 2 studies
2 other study(ies) available for neuropeptide-y and Gastrointestinal-Hemorrhage
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Innervation of an esophageal ectatic submucosal blood vessel in achalasia and a comparison with normals.
Achalasia is a disease of the esophagus characterized by incomplete relaxation of the lower esophageal sphincter, resulting in obstruction. Aperistalsis and dilation of the esophageal body occurs later, contributing to the esophageal dysfunction. Gastrointestinal bleeding in achalasia is an infrequent complication usually caused by stasis ulcer, esophageal varices, carcinoma, or pneumatic dilation of the sphincter. We describe here a patient with longstanding achalasia who bled vigorously from a proximal esophageal site that can be identified as arterial bleeding by endoscopy. Subsequent esophageal resection allowed detailed histological and immunohistochemical examination, which revealed a vascular ectasia. This lesion was associated with an unusually rich network of nerve fibers containing calcitonin gene-related peptide. Neuropeptide Y- and substance P-containing fibers were found to be decreased in this lesion as compared with controls. On the other hand vasoactive intestinal peptide- and nitric oxide synthase-containing fibers appeared quantitatively similar to those of controls. Calcitonin gene-related peptide is known to be involved in angiogenesis and may have played a causative role in the development of this lesion. Vascular ectasia may represent a hitherto unreported complication of achalasia. Topics: Blood Vessels; Calcitonin Gene-Related Peptide; Dilatation, Pathologic; Esophageal Achalasia; Esophagus; Female; Fluorescent Antibody Technique; Gastrointestinal Hemorrhage; Humans; Middle Aged; Mucous Membrane; Nerve Fibers; Neuropeptide Y; Neuropeptides; Substance P | 1994 |
Comparison of the effects of neuropeptide Y and noradrenaline on rat gastric mucosal blood flow and integrity.
1. The effects of neuropeptide Y (NPY) and noradrenaline on rat gastric mucosal blood flow, as estimated by laser Doppler flowmetry (LDF), have been examined. In addition, the ability of NPY and noradrenaline to induce acute mucosal haemorrhagic damage has also been assessed. 2. Close-arterial infusion of NPY (0.05-0.2 nmol kg-1 min-1) for 10 min in the anaesthetized rat induced a dose-dependent fall in LDF, but had minimal effects on systemic arterial blood pressure. Higher doses of NPY did not produce any further reduction in LDF. 3. Close-arterial infusion (0.1-0.4 nmol kg-1 min-1) of the structurally related peptide YY (PYY) or pancreatic polypeptide (PP), had inconsistent actions in decreasing LDF. 4. Close-arterial infusion of noradrenaline (30-90 nmol kg-1 min-1) dose-dependently reduced gastric LDF. 5. Local infusion of NPY (0.1 and 0.2 nmol kg-1 min-1) or noradrenaline (45 and 60 nmol kg-1 min-1) resulted in dose-related increases in the area of mucosal hemorrhagic damage. 6. Pretreatment with the alpha 1-adrenoceptor antagonist, prazosin (0.1 mg kg-1, i.v.) significantly reduced the effect of noradrenaline, but not NPY, on both LDF and mucosal damage. 7. These findings indicate that NPY and noradrenaline act directly on the gastric microvasculature to induce vasoconstriction and both can induce acute mucosal damage. Therefore endogenous NPY, like noradrenaline could play a modulatory role in regulating vascular tone and may influence mucosal integrity. Topics: Anesthesia; Animals; Blood Pressure; Dose-Response Relationship, Drug; Gastric Mucosa; Gastrointestinal Hemorrhage; In Vitro Techniques; Male; Neuropeptide Y; Norepinephrine; Pancreatic Polypeptide; Prazosin; Rats; Rats, Inbred Strains; Regional Blood Flow; Stomach Ulcer | 1991 |