Histamine H2 agonists

Very recently, a very bold chemical model for histamine H2-receptors has been proposed using [18]aneN6-3H+ 84), which can chemically recognize histamine, histamine H2-agonists, and histamine H2-antagonists such as cimetidine XII or ranitidine XIII that are currently in world-wide use for treatment of peptic ulcers 85). 

Franke, R. and Buschauer, A. (1993). Interaction Terms in Free-Wilson Analysis A QSAR of Histamine H2-Agonists. In Trends in QSAR and Molecular Modelling 92 (Wermuth, C.G., ed.), ESCQM, Leiden (The Netherlands), pp. 160-162. 

Buschauer, A., Friese-Kimmel, A., Baumann, G., and Schunack, W., Synthesis and histamine H2 agonistic activity of arpromidine analogues. Replacement of the pheniramine-hke moiety by non-heterocyclic groups, Eur. J. Med. Chem., 27, 321, 1992. 

Fechner GA et al. (1992) Antiproliferative and depigmenting effects of the histamine (H2) agonist dimaprit and its derivatives on human melanoma cells. Biochem Pharmacol 43(10) 2083-2090... 

Knieps, S., Michel, M.C., Dove, S. Buschauer, A. (1995) Non-peptide neuropeptide Y antagonists derived from the histamine H2 agonist arpromidine role of the guanidine group. Bioorg. Med. Chem. Lett. 5, 2065-2070. 

Holtje, H.-D. Sippl, W. Molecular modelling studies on histamine H2. and H3-receptor agonists. In Proceedings, XIVth International Symposium on Medicinal Chemistry Awouters, F. Ed. Elsevier Science B.V. Amsterdam, 1997 Vol. 28 pp. 137-148. 

Ganellin, G. R., Durant, G. J. Histamine H2-Receptor Agonists and Antagonists. In M. E. Wolff (Ed.), Burger s Medicinal Chemistry, (4th ed., Chapter 48). New York Wiley Sons, 1981. 

Figure 1.8. Histamine H2 receptors and receptor antagonists, a Function of histamine in the secretion of hydrochloric acid from the stomach epithelium. Hypersecretion promotes formation of ulcers, b Development of H2-receptor antagonists by variation of the agonist s stracture. Cimetidine was the first clinically useful antagonist.

HiSTAMiNE RECEPTOR AGONiSTS act at one or more of the three receptor types that have been defined - Hj, H2 and Hj. Histamine itself can act at any of these sites, which have a variety of contrasting properties. The basic properties of these will be described, then followed by a description of the pharmacology of histamine. Antagonists at these receptors are described under separate headings see HISTAMINE Hi-RECEPTOR ANTAGONISTS HISTAMINE Hj-RECEPTOR... 

Histamine H2-receptors are of the seven-transmembrane G-protein-coupled superfamily, and couple positively to the adenylyl cyclase (GJ pathway. Selective agonists include amthamine, dimaprit and impromidine. They also have actions at the other histamine receptor types impromidine and dimaprit have Hs-antagonist properties, and amthamine is a weak agonist at the H3 receptor. Also, 4(5)-methylhistamine has been used experimentally. 

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