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B Saffouri

Publications and source records attributed to B Saffouri.

6 recordsLinked to original sources

Identical patterns of somatostatin secretion from isolated antrum and fundus of rat stomach.

The patterns of somatostatin secretion from the fundus, the main source of somatostatin, and the antrum, the site of paracrine regulation of gastrin secretion, were examined using perifused antral and fundic segments from rat stomach. Gastrin secretion fundic segments from rat stomach. Gastrin secretion could be obtained from antral segments only. Somatostatin secretion was obtained from both antral and fundic segments. 1,1-Dimethyl-4-phenylpiperazinium (DMPP) (10(-5) and 10(-4) M) and bombesin-14 (10(-8) and 10(-6) M) caused concentration-dependent increases in somatostatin secretion that were of the same magnitude in antral and fundic segments. These increases were also of the same magnitude as those obtained in the vascularly perfused whole stomach. Atropine (3 X 10(-7) M) inhibited the somatostatin response to DMPP (10(-4) M) to the same extent in antral (50 +/- 12% inhibition) and fundic (55 +/- 12% inhibition) segments. Hexamethonium (10(-5) M) also inhibited the response to DMPP to the same extent in antral (80 +/- 9%) and fundic (78 +/- 19%) segments. Methacholine caused a typically muscarinic decrease in somatostatin secretion that was of the same magnitude in antral (27 +/- 6%) and fundic (25 +/- 6%) segments. The identical patterns of somatostatin secretion from the two regions of the stomach imply that somatostatin secretion measured in the vascularly perfused whole stomach is a valid reflection of somatostatin secretion by the antrum.

Animals

Healing of benign gastric ulcer. A placebo-controlled comparison of two dosage regimens of misoprostol, a synthetic analog of prostaglandin E1.

Misoprostol, a synthetic prostaglandin E1 methyl ester analog with gastric antisecretory and cytoprotective properties, prevents the development of acute experimental gastric and duodenal ulcers in various animal models. This study was designed as a multicenter randomized double-blind parallel-group comparison of the effects of two dosage strengths (25 and 100 micrograms q.i.d.) of orally-administered misoprostol and placebo on the healing of endoscopically-proven benign gastric ulcer in 299 out-patients. Safety was evaluated by comparison of pre- and post-treatment physical examinations, clinical laboratory tests, gastric antral biopsies and monitoring of adverse experiences. A statistically significant difference in gastric ulcer healing rate was seen at eight weeks among the treatment groups in the Intent-to-Treat Cohort: misoprostol 100 micrograms (62.0%), misoprostol 25 micrograms (50.0%), placebo (44.7%). The proportion of subjects healed in up to eight weeks of treatment was greatest in the misoprostol 100 micrograms group in all cohorts. Ulcer pain decreased in all treatment groups in successive weeks and there were no statistical differences among any of the three treatment groups. Diarrhea was the most frequently reported adverse experience: misoprostol 100 micrograms (9.8%), misoprostol 25 micrograms (7.7%), placebo (1.9%). The diarrhea was mild and self-limiting despite continued use of misoprostol. Overall evaluation of gastric antral biopsies showed no adverse changes in the morphology of the antral mucosa. We conclude that misoprostol 100 micrograms q.i.d. for up to eight weeks is safe and effective in the treatment of benign gastric ulcer.

Adult

Inhibition of neurally mediated gastrin secretion by bombesin antiserum.

In vitro studies on the vascularly perfused rat stomach have shown that gastrin secretion is regulated by intramural cholinergic and noncholinergic neurons. We have postulated that bombesin (gastrin-releasing peptide), a known gastrin stimulant present in antral mucosal nerve fibers, is the most likely candidate for noncholinergic transmitter. Bombesin antiserum (final dilution, 1:150) but not control serum added to the vascular perfusate inhibited the gastrin response to 1,1-dimethyl-4-phenylpiperazinium by 59 +/- 17% (P less than 0.01) and to electrical field stimulation by 60 +/- 16% (P less than 0.01), and its effect was additive to that of 10(-7) M atropine (75-94%), thus accounting for the greater part of neurally induced gastrin secretion. The effects of atropine and bombesin antiserum on somatostatin secretion were consistent also with blockade of cholinergic and noncholinergic neurons, respectively. The results indicate that bombesin and acetylcholine are the main intramural neural regulators of gastrin and somatostatin secretion. Acetylcholine acts predominantly to decrease the paracrine secretion of somatostatin, thereby eliminating the continuous restraint of somatostatin on gastrin secretion and enabling bombesin to exert its potent stimulatory effect on gastrin secretion.

Acetylcholine

Colonic involvement in salmonellosis.

Two cases of Salmonella colitis are described. Clinical and radiological differentiation from ulcerative colitis is difficult and necessitates repeated stool cultures. The management of Salmonella colitis is reviewed.

Adolescent