Inhibitory effect of glucagon, secretin and caerulein on gastric acid secretion stimulated by pentagastrin in patients with duodenal ulcer.

In 10 duodenal ulcer patients gastric acid secretion was stimulated by intravenous infusion of 1.5 microgram pentagastrin per kilogram hour. When acid secretion had reached a plateau, glucagon in a dose of 30 microgram per kilogram hour, secretin in a dose of 1 IU per kilogram hour or caerulein in a dose of 0.1 microgram per kilogram hour were infused into a separate vein for one hour during the intravenous infusion of pentagastrin. Using these doses, each drug produced about 30 per cent inhibition given separately. The highest degree of inhibition was obtained by the combination of glucagon and secretin. The inhibition reached the sum of the inhibitions after glucagon and secretin administered separately. Caerulein added to glucagon or secretin could slightly increase the inhibitory effect of these drugs given separately. Caerulein, however, failed to increase inhibition when glucagon and secretin were infused simultaneously.