pyrimidinones and Duodenal-Ulcer

We evaluated the effect of 20-, 40-, 60-, and 80-mg doses of SKF 93479, a new H2-receptor antagonist, on food-stimulated gastric acid secretion in duodenal ulcer patients. Medications were given as a single oral dose in the morning with a breakfast meal, and acid secretion was measured by in vivo intragastric titration in response to four blended steak meals infused into the stomach at intervals over a 24-hr period. A breakfast meal was infused immediately after medication; a luncheon meal was given 5 hr after drug, and a dinner meal was instilled 10 hr later. A second breakfast meal was infused 24 hr after medication. For comparison, the effect of 300 mg cimetidine, given as normally prescribed (with meals and at bedtime), on acid secretion was also studied. Food-stimulated acid secretion was inhibited in a dose-related manner by each of the four doses of SKF 93479. The antisecretory effect was most dramatic following the luncheon meal, and there was still significant (P less than 0.05) inhibition of acid secretion at the dinner meal with all doses of SKF 93479. With the second breakfast meal 24 hr after medication, the 80-mg dose alone achieved significant (P less than 0.05) inhibition of acid secretion. Inhibition of acid secretion was correlated positively with blood SKF 93479 levels. When compared with placebo results, serum gastrin concentration, measured 5 and 10 hr after medication, was significantly higher (P less than 0.05) with SKF 93479.

Topics: Adult; Aged; Cimetidine; Clinical Trials as Topic; Dose-Response Relationship, Drug; Duodenal Ulcer; Eating; Female; Gastric Acid; Gastrins; Histamine H2 Antagonists; Humans; Male; Middle Aged; Pyrimidinones

A new compound, IGN-2098 [5,6-dimethyl-2-[4-<3-(1-piperidinomethyl) phenoxy>cis-butenylamino]-4-(1H)-pyrimidone.2HCl], was found to be a potential histamine H2-receptor antagonist in the guinea pig atrium. IGN-2098, given p.o., significantly and persistently (for more than 12 hr) inhibited the basal gastric secretion in pylorus-ligated rats. The agent also significantly inhibited the basal gastric secretion when given by the s.c.-, i.d.- or i.p.-route. Stimulated gastric secretion in fistula rats in response to histamine, carbachol or pentagastrin was also significantly inhibited with IGN-2098 given s.c. Pretreatment with IGN-2098 (p.o.) significantly protected the gastric mucosa against pylorus ligation-, water-immersion stress-, histamine-, indomethacin-, HCl.aspirin-, and HCl.ethanol-induced gastric lesions. In addition, the agent significantly protected the duodenal mucosa against mepirizole-induced ulcers. Based upon the ED50 values, the antisecretory effects on histamine, carbachol or pentagastrin-stimulated acid secretion were 6.0, 37.0 or 80 times more potent than roxatidine, respectively. As to the anti-lesion effects on HCl.aspirin-induced gastric lesions or mepirizole-induced duodenal ulcers, IGN-2098 was 8.1 or 14.8 times more potent than roxatidine, respectively. These results suggest that IGN-2098 will be a useful drug for the treatment of gastric and duodenal lesions in man.

Topics: Animals; Anti-Ulcer Agents; Dose-Response Relationship, Drug; Duodenal Ulcer; Gastric Juice; Histamine H2 Antagonists; Male; Piperidines; Pyrimidinones; Rats; Rats, Inbred Strains; Stomach Ulcer