gastrins and benzilonium-bromide

The influence of cholinergic blockade as well as vagal denervation of the oxyntic gland mucosa on the gastrin response to gastrin-releasing peptide (GRP) have been studied in patients with duodenal ulcer disease. The gastric luminal content was neutralized during the experiments. GRP induced a substantial increase in gastrin levels with a peak response already after 15 min of infusion. Vagal denervation of the parietal cell area induced a significant increase in basal gastrin concentrations and a significant enhancement of the GRP response. Two different doses of benzilonium bromide were studied and neither influenced the basal concentrations of gastrin. A significantly increased gastrin response to GRP was, however, observed after administration of both a high and a very low dose of the anticholinergic drug. Our results delineate a vagal, noncholinergic inhibitory influence on the basal gastrin release. In addition a vagally dependent oxyntopyloric mechanism inhibits the gastrin release stimulated by GRP. This inhibitory mechanism may hypothetically be a cholinergic reflex mechanism.

Topics: Bombesin; Duodenal Ulcer; Female; Gastrin-Releasing Peptide; Gastrins; Humans; Male; Middle Aged; Parasympatholytics; Peptides; Pyrrolidines; Vagotomy, Proximal Gastric

Plasma gastrin concentrations and gastric acid output after modified sham feeding were determined in 20 duodenal ulcer patients. Sham feeding produced an acid response corresponding to 40-68% of the maximal acid output after pentagastrin stimulation, with no significant increase of plasma gastrin concentrations. In eight patients proximal gastric vagotomy almost abolished the acid responses to both insulin hypoglycaemia and sham feeding. Sham feeding in the vagotomised patients did not change the gastrin concentrations in plasma. After pretreatment with benzilonium, an anticholinergic with minimal central nervous effects, plasma gastrin concentrations increased after sham feeding. The study confirms that sham feeding is a poor stimulus for gastrin release in duodenal ulcer patients and supports a cholinergic inhibition of gastrin release. Intravenous injection of benzilonium bromide in a dose close to 70 micrograms/kg, and atropine in the low dose of 30 micrograms/kg inhibited the acid response to sham feeding by about 65%. Atropine in a dose of 50 micrograms/kg virtually abolished the acid sham feeding response, possibly owing to ganglionic or central nervous blockade. Vagal activation of the acid secretory glands does not seem to involve a purely cholinergic neurotransmission.

Topics: Adult; Aged; Atropine; Benzilates; Depression, Chemical; Duodenal Ulcer; Eating; Gastric Juice; Gastrins; Humans; Insulin; Male; Middle Aged; Parasympatholytics; Pentagastrin; Pyrrolidines; Stomach; Vagotomy

The effects of the anticholinergic drug benzilonium bromide and the opiate receptor blocker naloxone, given alone or in combination, on the acid secretory response and on plasma gastrin releasing peptide (GRP) response to sham feeding was tested in eight duodenal ulcer (DU) patients. Naloxone alone had no effect on the acid secretion after sham feeding. Benzilonium reduced basal acid secretion and the acid response to sham feeding but did not abolish the response. The combination of benzilonium and naloxone was not more effective than benzilonium alone. Neither drug, nor the combination had any effect on plasma GRP following sham feeding. It is concluded that enkephalins are unlikely to participate in the acid response to sham feeding in patients with DU.

Topics: Adult; Duodenal Ulcer; Enkephalins; Gastric Juice; Gastrin-Releasing Peptide; Gastrins; Humans; Male; Middle Aged; Naloxone; Peptides; Pyrrolidines; Stomach; Vagus Nerve