Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The present study has been made in anesthetized rats to characterize conditions of exposure to acid and extent of ischemia which determine the development of gastric hemorrhage. Gastric hemorrhage occurred in rats subjected to shock during exposure of the gastric lumen to acid after the reinfusion of withdrawn blood. When the acid concentration was constant, bleeding was dependent on the degree of shock. When hemorrhage shock was constant, bleeding from the stomach appeared pH dependent, although this did not quite achieve statistical significance. Cimetidine 2 x 10(-6) mol kg-1 min-1 (30 mg kg-1 hr-1) and 1 x 10(-5) mol kg-1 min-1 (150 mg kg-1 hr-1) significantly reduced gastric hemorrhage whether given prophylactically before gastric injury or therapeutically after completion of gastric injury. Because protection can be demonstrated against an injury involving exogenous acid and after the injury has been established, it is probable that the effectiveness of cimetidine in these studies is independent of its antisecretory effects.
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PMID:Reduction by cimetidine of acute gastric hemorrhage caused by reinfusion of blood after exposure to exogenous acid during gastric ischemia in rats. 3 72

Mechanisms of gastric bleeding under obstructive jaundice were studied in adult male Wistar rats. Following ligation of the common bile duct, mucosal noradrenaline significantly decreased in both the pyloric and fundic gland areas of the gastric mucosa by 20 days after the operation. Serotonin increased only in the pyloric gland area, and histamine increased in the fundic gland area. Urinary excretion of free noradrenaline significantly increased after the ligation. Three weeks after the ligation, restraint and water immersion experiments were conducted. Under water immersion, gastric blood flow significantly reduced in rats with obstructive jaundice compared to controls. Acid output decreased in both groups. Gastric bleeding was noted in the fundic gland area significantly earlier in the ligated rats than in the non-ligated rats. Administration of noradrenaline s.c. 30 minutes before immersion significantly blocked the reduction in gastric blood flow and protected the gastric mucosa against acute bleeding under immersion. These results suggested that prolonged obstructive jaundice may deplete noradrenaline in the gastric mucosa, and that gastric mucosal ischemia caused by this sympathetic dysfunction plays an important role in the formation of acute gastric bleeding under obstructive jaundice.
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PMID:Studies of the mechanisms of gastric bleeding under obstructive jaundice. Role of biogenic amines. 660 80

We examined the effect of egualen, a stable azulene derivative, against gastric damage induced by ischemia/reperfusion (I/R), gastric bleeding induced by double antiplatelet therapy with aspirin (ASA) plus clopidogrel, and small intestinal damage generated by loxoprofen, and investigated the possible mechanisms involved in its protective action. Male C57BL/6 mice or SD rats were used under urethane anesthesia (gastric lesions) or in a conscious (intestinal lesions) state. I/R-induced gastric injury was produced in mice by clamping the celiac artery for 30 min, followed by reperfusion for 60 min. Gastric bleeding was induced in rats by luminal perfusion with 25 mM ASA+50 mM HCl for 2 hours in the presence of clopidogrel (30 mg/kg). To produce small intestinal lesions the rats were given loxoprofen (60 mg/kg) p.o. and killed 24 hours later. Egualen was given i.d. 60 min before I/R or ASA perfusion, while given p.o. twice 30 min before and 6 hours after loxoprofen. Egualen significantly prevented the I/R-induced gastric damage, and the effect was equivalent to that of seratrodast (TXA2 antagonist). This agent also significantly suppressed gastric bleeding induced by ASA plus clopidogrel, similar to PGE2. Likewise, egualen significantly prevented loxoprofen-induced damage in the small intestine, accompanied by an increase in the secretion of mucus and suppression of bacterial invasion as well as iNOS expression. These results suggest that egualen has a prophylactic effect against various lesions in the gastrointestinal mucosa, probably through its characteristic pharmacological properties, such as TXA2 antagonistic action, local mucosal protection, and stimulation of mucus secretion.
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PMID:Prophylactic effect of egualen sodium, a stable azulene derivative, on gastrointestinal damage induced by ischemia/reperfusion, double antiplatelet therapy and loxoprofen in rats. 2356 73