Influence of surgical sympathectomy on gastric secretion and ulceration in rats

The influences of sympathectomy on gastrointestinal mucosa, gastric secretion, acute or chronic gastric ulcers were studied in rats. Uncer ether anesthesia, sympathectomy was performed by surgical removal of the celiac ganglion. Surgical sympathectomy per se produced no pathological changes in the gastrointestinal tract as determined by macroscopical observation 3, 10 or 20 days after operation. The volume of gastric juice and pepsin output were not influenced by the sympathectomy but gastric acid output was significantly increased in pylorus-ligated rats. The sympathectomy worsened the stress- and the indomethacin-induced ulcer and delayed the healing of chronic gastric ulcers a little but not significantly, and had no deteriorative influence on the reserpine-induced ulcers. In contrast, Shay ulcers, aspirin- or secrotonin-induced ulcers were significantly aggravated by sympathectomy. The loss of H+ ions and gain of Na+ ions in the gastric juice of pylorus-ligated and aspirin-treated rats were not affected by sympathectomy.

Effects of cimetidine on healing of chronic gastric and duodenal ulcers in dogs

The effects of cimetidine on healing of gastric and duodenal ulcers induced in mongrel dogs were studied. Gastric ulcers were produced by subserosal injection of acetic acid solution and duodenal ulcers by topical application of acetic acid on the serosal surface of the duodenum. Oral treatment with cimetidine, 450 mg/dog/day in three divided doses for 14 days, produced a remarkable acceleration of healing of duodenal ulcers but exerted little influence on gastric ulcers.

Effects of cimetidine, a histamine H2-receptor antagonist, on various experimental gastric and duodenal ulcers

The effects of cimetidine, a new histamine H2-receptor antagonist, on the development of experimental gastric and duodenal ulcers were studied. It was found that either by the oral, intraduodenal, or intraperitoneal route this agent had a marked inhibitory activity on stress-, aspirin-, indomethacin-, or histamine-induced gastric ulcers in rats and guinea pigs. The effects of cimetidine on stress-, aspirin-, and indomethacin-induced gastric ulcers were dose-dependent in many cases. Pylorus-ligation uclers, reserpine- or serotonin-induced gastric ulcers were little influenced by cimetidine. Duodenal ulcers induced by continuous infusion of carbachol-histamine were significantly inhibited by a simultaneous infusion of cimetidine. An analysis of gastric contents in pylorus-ligated rats after stressing indicated a decreased volume and acid output as the result of intraduodenal cimetidine treatment. In contrast, cimetidine exerted little influence on gastric secretion in rats treated with aspirin or in guinea pigs treated with histamine. Thus, the mechanism of action of cimetidine in preventing gastric or duodenal ulcers is likely to occur by suppression of gastric secretory function in a duodenal ulcer model but by suppression of other unknown ulcerogenic factors in gastric ulcer models.

Effects of metiamide and propranolol on gastric secretion in anesthetized dogs

The effects of metiamide, a histamine H2-receptor antagonist, and propranolol, a beta-adrenergic blocking agent, on gastric secretion were studied in anesthetized dogs. Metiamide, 1.45 mg/kg i.v., markedly inhibited the gastric secretion induced by a continuous i.v. infusion of tetragastrin (8 microng/kg-hr), histamine dihydrochloride (160 microng/kg-hr), or methacholine bromide (100 microng/kg-hr). Propranolol 0.5 or 1.0 mg/kg i.v. produced a significant potentiation of tetragastrin-induced gastric secretion but no influence of the secretion induced by methacholine. Propranolol at 5 or 10 mg/kg i.v. produced a slight reduction of the tetragastrin-induced secretion and a significant reduction of methacholine-induced secretion. Histamine-induced gastric secretion was not affected by propranolol at either 1 and 10 mg/kg i.v. These findings lend support to the hypothesis that interactions among histamine, gastrin and acetylcholine receptors do occur though the degree would not be the same in all directions.

Effects of cimetidine and atropine sulfate on gastric secretion and healing of gastric and duodenal ulcers in rats

Cimetidine, a new histamine H2-receptor antagonist (50 or 100 mg/kg) and atropine sulfate (15 mg/kg) given intraduodenally, markedly inhibited gastric secretion in pylorus-ligated rats. Cimetidine (100 or 200 mg/kg/day) given for 10 or 12 consecutive days orally in two divided doses, significantly promoted the healing rate of both gastric and duodenal ulcers induced in rats. Atropine (30 mg/kg/day) also significantly accelerated the healing of duodenal ulcers but failed to affect gastric ulcers.

Influence of aspirin on healing of chronic gastric ulcers in dogs

Gastric ulcers induced in dogs by transserosal injection of 1 ml of 40% acetic acid healed completely by the 7th week after ulceration and never reulcerated during the observation period up to 12 weeks. Acetic acid ulcers in the active (at 1 week), quiescent (3 weeks) or healed (at 7 weeks) stages were not influenced by the daily administration of aspirin 2 g/dog/day for for 5 consecutive weeks. All examinations were done by gastroscopy in addition to macroscopical and histological observations at autopsy.

Effects of L-glutamine on acetylsalycylic acid induced gastric lesions and acid back diffusion in dogs

Effects of L-glutamine on acetylsalicylic acid (ASA)-induced gastric mucosal lesions were studied in mongrel dogs. It was confirmed that when oral ASA at 1.0 or 2.0 g per dog is given in two divided doses, there is severe and consistent dose-dependent mucosal damage in the glandular portion of the stomach in fasted dogs. However, when L-glutamine 2.0 or 4.0 g per dog in two divided doses is given concomitantly with ASA 2.0 g per dog orally, the gastric irritation is significantly inhibited. Instillation of 20 mM of ASA in 100 mM HCl solution into the Heidenhain pouch of Beagle dogs produced a significant loss of H+ from the pouch and a gain of Na+ in the lumen compared with ASA-free controls. When L-glutamine (100 mM) was given concomitantly with ASA (20 mM) into the pouch, changes of electrolyte fluxes in response to ASA alone were significantly suppressed. However, 50 mM of L-glutamine had no appreciable effect on acid back diffusion caused by ASA 20 mM. The amino acid itself had little effect on the ionic movement in the pouch. Gross bleeding from the pouch treated with ASA was never observed with the concomitant dosing of ASA and L-glutamine 50 or 100 mM.

[Findings in the gastric mucosa and gastric secretion in rats treated with methyl O-(4-hydroxy-3-methoxycinnamoyl)reserpate (CD-3400) and reserpine derivatives]

CD-3400 developed by Nippon Chemiphar Co. Ltd., is a new antihypertensive agent belonging to the class of rauwolfa alkaloids. Influence of the agent on gastric mucosa, healing process of acetic acid-induced gastric ulcer and gastric juice in rats was investigated and compared with effects of reserpine and rescinnamine. CD-3400-induced gastric lesions were fewer in number than those produced with reserpine and rescinnamine in fasted rats. After a three day treatment of CD-3400 to fed rats, however, there were few gastric lesions, while reserpine- and rescinnamine-induced gastric lesions were aggravated to a greater extent that when a single administration was given to fasted rats. Influence of CD-3400, reserpine and rescinnamine on the healing process of acetic acid-induced ulcer was insignificant, but treatment with high doses of reserpine and rescinnamine resulted in death. Pretreatment with CD-3400 and reserpine produced a decrease in gastric acid and K+, and an increase in Na+. Repeated administration of reserpine for 5 days resulted in a decrease of both gastric volume and acid, while such was not seen with CD-3400. Treatment with anticholinergic agents such as atropine sulfate and atropine methylbromide inhibited CD-3400- and reserpine-induced gastric lesions. From these results, it would appear that cholinergic factors play a role in the pathogenesis of CD-3400-induced gastric lesions, as in the case with reserpine, and that the responses of these lesions to reserpine and CD-3400 correlate with changes of ionic fluxes in gastric juice.

Influence of pregnancy on the development of various gastric lesions in rats

The influence of pregnancy, and to some extent lactation, on various gastric lesions in rats were studied. Shay ulceration and gastric lesions induced by cold-restraint stress and ulcerogenic agents, such as acetylsalicylic acid (ASA), reserpine, or epinephrine, in rats were significantly aggravated by pregnancy (day 20 of pregnancy). Gastric hypersecretion, which was observed during pregnancy in pylorus ligation preparation, appears to contribute to the mechanism of aggravation of gastric lesions. ASA induced a marked back-diffusion of acid in pregnant rats which might resulted in the aggravation of ASA-induced gastric lesions. In contrast, histamine-induced gastric lesions were markedly inhibited according according to the progress of pregnancy but after 10 days' lactation returned to the level seen in nonpregnant rats. The histaminase inhibitor aminoguanidine strongly aggravated the histamine-induced gastric lesions in pregnant rats as compared with the non-pregnant ones.

A new model of stress ulcer in the rat with pylorus ligation and its pathogenesis

Water-immersion stress for 7, 14, or 20 hr consistently induced linear or punctate stress ulcers (mucosal erosions) in the corpus of the stomach in intact rats. When the pylorus of the stomach had been ligated prior to stressing, the stress ulcers changed their morphological feature (mainly punctate and in one place elongated) and location (both in corpus and antrum). Histologically, the stress ulcer developed in the proximal antrum of pylorus ligated rats and penetrated into the muscularis mucosa. Sodium bicarbonate, chlorpromazine, hexamethonium, atropine, metiamide, and bilateral vagotomy markedly inhibited the stress ulcers which developed in the pylorus-ligated rats. Phentolamine and propranolol hardly affected the development of stress ulcers. Amylopectine evoked a new type of stress ulcer in the corpus when it was given to the pylorus-ligated rats.

Effects of carbenoxolone Na on acute and chronic gastric ulcer models in experimental animals

Effects of carbenoxolone Na on acute or chronic types of gastric lesions or ulcer models produced in rats, guinea pigs, or dogs were studied. Carbenoxolone Na, given either orally or intraperitoneally, produced a significant inhibition of stress-induced gastric lesions in intact or in pylorus-ligated rats. Acetylsalicylic acid (ASA)-induced or serotonin-induced gastric lesions in rats were also inhibited significantly by pretreatment with the drug. However, carbenoxolone Na did not affect the development of Shay ulceration in rats even though the peptic activity in gastric juices was markedly reduced by the drug. Histamine-induced gastric lesions in guinea pigs were not prevented by pretreatment with carbenoxolone Na. Although carbenoxolone Na, given for 10-20 days, did not promote the healing of stress-induced gastric lesions and acetic acid gastric jlcers in rats, it significantly accelerated the healing of chronic gastric ulcer produced in dogs by 3 weeks' treatment. Carbenoxolone Na prevented the acid back-diffusion caused by ASA without any influence on Na+ efflux in pylorus-ligated rats.

Effects of L-glutamine of acetylsalicylic acid or taurocholic acid-induced gastric lesions and secretory changes in pylorus-ligated rats under normal or stress conditions

An oral dosing of either acetylsalicylic acid (ASA) or taurocholic acid (TCA) to pylorus-ligated rats subjected to water-immersion stress produced severe damage to the gastric musoca in contrast to the irritation observed in non-stressed ones. The irritative activity of ASA or TCA on gastric mucosa under stress was dose-dependent. Stress itself (23 degrees C, 7 hr) did not induce any appreciable changes in gastric mucosa under stress wasic mucosa of rats. L-glutamine, given together with SAS or TCA, significantly prevented the potentiated development of SAS- or TCA-induced gastric lesions in stressed rats. L-glutamine also prevented in varying degrees the reduction of acid and increment of Na+ ion in gastric juice accumulated in stressed rats in response to ASA or TCA.

An experience in clinical application of real-time two-dimensional echocardiography

An experience with a real-time two-dimensional echocardiographic system was presented. In this report a sagittal plane section, i.e., the section which was parallel to the long axis of the left ventricle was used. The two-dimensional section of the normal heart, mitral stenosis, interventricular septal defect (preoperatively and postoperatively), mitral prosthetic valve, pericardial effusion, and acute myocardial infarction were studied. Easy applicability, quick recording, and non-invasive nature of the procedure, make the indications widened including acutely distressed patients. We conclude that real-time two-dimensional echocardiography is one of the most promising cardiac examinations.