Effect of endothelium-derived relaxing factor on the gastric lesion induced by HCl in rats.
Effect of HCl on the endothelium-dependent increase in mucosal blood flow and effect of endothelium-derived relaxing factor (EDRF) inhibitors or nitrites on the HCl-induced gastric lesion were studied to clarify the effect of EDRF on the formation of gastric lesion in rats. Topical application of 0.6 N HCl on the gastric mucosa inhibited the endothelium-dependent increase in mucosal hemodynamics estimated using organ-reflectance spectrophotometry induced by vagal stimulation or acetylcholine, but not by papaverine. Collagenase, gossypol, hemoglobin and ascorbic acid have been reported to inhibit the endothelium-dependent vasodilation, inhibited increase in mucosal hemodynamics induced by vagal stimulation and acetylcholine. These inhibitors and methylene blue significantly enhanced the gastric lesion induced by 0.45 N HCl. Intra-arterial or topical application of nitrites (sodium nitrite and isoamyl nitrite) increased mucosal hemodynamics. Oral administration of nitrites prevented the formation of 0.6 N HCl-induced gastric lesion. These results suggest that EDRF plays an important role in the protection of gastric mucosa against HCl. Reduced endothelium-dependent increase in mucosal blood flow may be an etiology of gastric lesion in rats.
Kitagawa
H
H
Department of Pharmacology, Nippon Boehringer Ingelheim, Kawanishi Pharma Research Institute, Hyogo, Japan.
Takeda
F
F
Kohei
H
H
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D004347:Drug Interactions; D004558:Electric Stimulation; D005753:Gastric Mucosa / Q000187:drug effects*; D006439:Hemodynamics / Q000187:drug effects; D006851:Hydrochloric Acid; D008297:Male; D003012:Microbial Collagenase / Q000494:pharmacology; D009569:Nitric Oxide / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D009573:Nitrites / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D013276:Stomach Ulcer / Q000139:chemically induced; D014630:Vagus Nerve / Q000502:physiology
D009573:Nitrites; D009569:Nitric Oxide; D003012:Microbial Collagenase; D000109:Acetylcholine; D006851:Hydrochloric Acid