Alteration of H2 receptor sensitivity in duodenal ulcer patients after maintenance treatment with an H2 receptor antagonist.

Abstract

SUMMARY The effects of a specific H2 receptor agonist impromidine, on gastric acid secretion were measured in six patients with duodenal ulcer in clinical remission before and after three months treatment with ranitidine 150 mg nocte. After treatment basal acid output increased from 1 2 to 2-8 mmol/h and after maximal impromidine stimulation from 36-9 (4 7) to 44-2 (6 2) mmol/h (p<002). Intravenous ranitidine 50 mg was given at the end of the impromidine infusion on each study day; the antisecretory effect of intravenous ranitidine was accentuated after the treatment with ranitidine from a trough acid output of 8 5 (1-2) mmol/h before, to 3-8 (1-5) mmol/h (p<0 05) after, treatment. The increased response to the H2 agonist impromidine and the H2 antagonist ranitidine after treatment with ranitidine suggests an enhanced sensitivity of the H2 receptor. This might be explained on the basis of an increase in the number of H2 receptors ('up-regulation'). a highly potent, and specific agonist for the H2 receptor' exhibiting up to 27 times the affinity of histamine.9 In this study we have examined the effect of three months of treatment with ranitidine 150 mg nocte on impromidine stimulated gastric acid secretion in six patients with duodenal ulcer in remission.

Effect of FRG-8813, a New-Type Histamine H₂-Receptor Antagonist, on the Recurrence of Gastric Ulcer after Healing by Drug Treatment in Rats

“…In this study, FRG-8813 did not induce the rebound hyperacidity after withdrawal of it in comparison with famotidine and cimetidine. The mechanisms to explain the rebound hyperacidity involve hypergastrinemia [27], proliferation of G cells [9], and alteration of H 2 -receptor sensitivity [28]. The present study showed that FRG-8813 did not induce hypergastrinemia.…”

Anti-ulcer effect of rhizome of Curcuma longa Linn, by the method of pyloric ligation

“…15 Parietal cell hypersensitivity or up-regulation has been documented after cessation of treatment with H2-receptor antagonists. 16 It may be the reason for the early relapse associated with treatment by H2-receptor antagonists comparing with treatment by drugs like colloidal bismuth, sucralfate and carbenoxolone sodium, which does not make many changes with the physiologic process of acid secretion. In the present study it is found that extract of Curcuma longa is not making much difference in gastric fluid volume and acidity.…”

Maintenance Treatment with H₂Receptor Antagonists for Duodenal Ulcer Disease: Toward a Rational Use

“…Early studies failed to show any increase in the secretory response of gastric acid secretion to exogenous stimuli over days or weeks of treatment with H2 receptor antagonists [36], Recently, however, a series of studies have demonstrated that some degree of tolerance develops during continued dosing [37][38][39][40], This phenomenon seems to begin after only a few days, at the doses commonly used [41 ]. In clinical practice this drop in efficacy was first observed in patients being treated for the Zollinger-Ellison syndrome, in whom it proved necessary to increase the drug dosage progres sively after some months in order to maintain adequate suppression of gastric acidity [42], It has been speculated that tolerance might be implicated in failure of ulcers to heal, or in some of the early relapses during maintenance therapy [38], Two studies have studied tolerance to stan dard [39] and high-dose [40] administration of all available H2 receptor antagonists by measuring the 24-hour intragastric acidity in volunteers at baseline and on days 1,15 and 29 of medication.…”