Two Distinct Pathways for Histamine H2 Receptor Down-regulation

Two distinct pathways for histamine H2 receptor down-regulation. H2 Leu124 --> Ala receptor mutant provides evidence for a cAMP-independent action of H2 agonists.

Pretreatment of Chinese hamster ovary cells expressing the histamine H2 receptor (CHOrH2 cells) with histamine resulted in a time-dependent (t1/2 approximately 7 h) and dose-dependent (EC50=18 nM) H2 receptor down-regulation measured as [125I]iodoaminopotentidine binding (44+/-10% down-regulation). Pretreatment of CHOrH2 cells with cholera toxin or forskolin also led to H2 receptor down-regulat...

Histamine H2 receptor trafficking: role of arrestin, dynamin, and clathrin in histamine H2 receptor internalization.

Agonist-induced internalization of G protein-coupled receptors (GPCRs) has been implicated in receptor desensitization, resensitization, and down-regulation. In the present study, we sought to establish whether the histamine H2 receptor (H2r) agonist amthamine, besides promoting receptor desensitization, induced H2r internalization. We further studied the mechanisms involved and its potential r...

Novel insights into histamine H2 receptor biology

Del Valle, John, and Ira Gantz. Novel insights into histamine H2 receptor biology. Am. J. Physiol. 273 (Gastrointest. Liver Physiol. 36): G987–G996, 1997.—Histamine exerts multiple biological actions through one of three receptor subtypes (H1, H2, and H3). This review focuses on new developments regarding the structure and function of the H2 receptor. In addition to the important role this rece...

[Structural analysis of the histamine H2 receptor].

In gastric parietal cells the histamine H2 receptor is involved in gastric acid secretion. Molecular cloning of the cDNA for the histamine H2 receptor has revealed that the receptor is a member of the G-protein coupled receptor family. We expressed histamine H2 receptors in CHO cells, COS7 cells, and Sf9 cells to analyze N-glycosylation, palmitoylation, and desensitization of the H2 receptor, w...

Release of histamine by H2-receptor antagonists?