The Interaction of Histamine with Gastrin and Carbamylcholine on Oxygen Uptake by Isolated Mammalian Parietal Cells

Abstract

A B ST RA CT Using oxygen uptake as an index of the physiological response of isolated parietal cells, the interactions between histamine and gastrin and between histamine and carbamylcholine and the effects of atropine and metiamide on these interactions have been studied. Parietal cells were isolated from canine fundic mucosa by sequential exposure of separated mucosa to collagenase and EDTA. In previous studies carbamylcholine, isobutyl methyl xanthine, gastrin, and histamine have each been shown to increase oxygen uptake by these cells. Isobutyl methyl xanthine greatly enhanced the histamine effect. Carbamylcholine was inhibited by atropine but not by metiamide, histamine was inhibited by metiamide but not by atropine, and gastrin was inhibited by neither, suggesting that each of these agents has a direct action on the parietal cell. In the present studies, potentiating interactions between histamine and carbamylcholine and between histamine and gastrin have been demonstrated. Against a histamine (0.1 and 1 ,M) plus isobutyl methyl xanthine (0.1 mM) background, the dose for 50% response for gastrin was approximately 1 nM, and the maximal response was obtained at 0.1 AM.When added to these combinations of stimulants, metiamide and atropine retained their respective specificities against stimulation by histamine and carbamylcholine, in that responses were inhibited to the level that was seen when the component of the pair that was not inhibited was given alone.The observation that histamine plus gastrin andThis work was presented, in part, at the meeting of the

L-365,260, a Potent CCK-B/Gastrin Receptor Antagonist, Suppresses Gastric Acid Secretion Induced by Histamine and Bethanechol as Well as Pentagastrin in Rats.

“…An in vitro studied showed that a low con centration of gastrin which had only a slight effect on acid secretion by itself potentiated acid secretion induced by histamine, which dif fered from gastrin in intracellular signal trans duction (11). The present results on L-365,260 suggest that serum gastrin which basally exists in the blood flow may also potentiate histamine-induced gastric acid secretion in vivo.…”

Abnormal functional and morphological regulation of the gastric mucosa in histamine H2 receptor–deficient mice

“…Soll and colleagues have demonstrated that each receptor for ACh, gastrin, and histamine is separately expressed on an isolated canine parietal cell and have provided evidence for postreceptor synergism (6,7,24,25). A combination of signals induced by histamine and either ACh or gastrin synergistically evoked acid secretion, which was greater than the additive effect of each agent.…”

THE GASTRIC ANTISECRETORY ACTIONS OF PROSTAGLANDIN E2 AND STABLE PROSTACYCLIN ANALOGUES AGAINST DIFFERENT SECRETAGOGUES IN PERFUSED WHOLE‐STOMACHS OF RAT OR MOUSE in vitro

“…Interestingly, Soll (1978bSoll ( , 1980 has observed that a background of histamine stimulation not only greatly enhanced the isolated parietal-cell responses to carbachol and gastrin but also made these responses susceptible to inhibition by PGE2. In isolated whole stomach or in stripped mucosal preparations, there is a mixture of cell types, some of which are capable of mediator release, including histamine.…”