Histamine H, receptor

Leurs, R., Traiffort, E., Arrang, J. M., Tardivel-Lacombe, J., Ruat, M. and Schwartz, J.-C. Guinea pig histamine H receptor. II. Stable expression in Chinese hamster ovary cells reveals the interaction with three major signal transduction pathways. /. Neurochem. 62 519-527,1994. 

Bakker, R. A., Wieland, K., Timmerman, H. and Leurs, R. Constitutive activity of the histamine H[ receptor reveals inverse agonism of histamine H receptor antagonists. Eur. J. Pharmacol. 387 R5-R7, 2000. 

Fredrickson, P. A., and Richelson, E. (1979) Hallucinogens antagonize histamine H, receptors of cultured mouse neuroblastoma cells. Eur. J. Pharmacol., 56 261-264. 

Interestingly, penicillamine—a degradation product of penicillin and phenothiazines—the histamine H,—receptor antagonists, such as promethazine teoclate, methadilazine hydrochloride, trimeprazine tartrate are found to increase the cholesterol levels. 

Histamine H receptor Histamine Hj receptor Histamine H3 receptor Histamine H4 receptor... 

Lovenberg TW, Roland BL, Wilson SJ, Jiang X, Pyati J, Huvar A, Jackson MR, Erlander MG Cloning and functional expression of the human histamine H, receptor. Mol Pharmacol 1999 55 1101-1107. 

Schwartz, 1. C., Morisset, S., Rouleau, A., et al. (2003) Therapeutic impUcations of constitutive activity of receptors the example of the histamine H receptor. J. Neural. Transm. Suppl. 1-16. 

Mirtazapine is a potent antagonist of 5-HT2 and 5-HT3 receptors. It is a potent antagonist of histamine (H- ) receptors and a moderate antagonist at muscarinic... 

Three types of histamine (H) receptors have been isolated. At present, it appears that receptor blockade... 

Somnolence. As one would expect, given the histamine H] receptor antagonism, somnolence is a common side effect of olanzapine. Somnolence and psychomotor slowing are dose dependent, and patients often become tolerant to this side effect over time. 

Inhibit basal and nocturnal gastric secretions by competitively and reversibly inhibiting the action of histamine at the histamine H -receptors of parietal cells... 

Most substituted imidazoles are obtained via the condensation of non-cyclic fragments to form the desired imidazole. The majority of these condensation reactions has recently been reviewed by Grimmett8. The largest number of imidazoles obtained via condensation approaches is only of limited use for the development of histaminergic ligands as they are mainly polysubstituted imidazoles. For the histamine receptors proper substitution of the imidazole ring is usually limited to the 4(5)-position, with the exception of the histamine H]-receptor, where a broader range of substituents on the 2-position is tolerated. 

The Histamine H Receptor 1998 Elsevier Science B.V. All rights reserved. 

Schizophrenia is currently viewed as a complex, at least in part neurodevelomental disorder of unknown etiology. A number of structural changes in schizophrenic brains have been described, and changes in dopaminergic functions are associated with many other neurotransmitter and receptor changes54 60 7. Reduced of histamine H, receptor binding in... 

In summary, histamine H3-antagonists such as thioperamide and clobenpropit in combination with zolantidine, a histamine H2-receptor antagonist, ameliorated the scopolamine-induced effect. This ameliorating effect was mediated through histamine H3 receptors and/or histamine H, receptors. 

These data suggest that the contribution of the cholinergic system to the ameliorating effect induced by histamine H3-receptor antagonists is not mediated by histamine H3 hetero receptors, but by postsynaptic histamine H, receptors. This is supported by previous reports that histamine excites cholinergic neurons through histamine H, receptors [30, 31]. 

An interesting observation in our structure-activity studies was that ethylamine, a part of the histamine molecule, 4-(2-ethylamine)imidazole, known for a long time to be a potent stimulator of gastric secretion, also produced duodenal ulcers in rats (20,22). Furthermore, structural similarities also exist between dopamine and histamine H receptor antagonists metiamide and cimetidine (23,24). 

Raymond JR, Albers FJ, Middleton JP, et al. 5-HT1A and histamine H, receptors in HeLa cells stimulate phosphoinositide hydrolysis and phosphate uptake via distinct G protein pools. J Biol Chem 1991 266 372-379. 

The affinities (Tab. 13.1) and rank order of affinities (Tab. 13.2) of clozapine-type compounds clearly show that their primary receptor targets are serotonin (excep. 5-HTj), histamine Hj and adrenergic receptors, followed by dopamine receptors. Whilst clozapine and olanzapine seem to have some similarities in their overall receptor profile, quetiapine differs from them not only in the significantly lower absolute affinity values but also in the rank order of potencies that is, it has the highest affinity for adrenergic alpha-1 and histamine H, receptors followed by 5-HT2A and dopamine receptors. 

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