Description
Imetit is a histamine H
3 and H
4 receptor agonist (K
is = 0.3 and 2.7 nM, respectively, in radioligand binding assays). It is selective for histamine H
3 and H
4 receptors over H
1 and H
2 receptors at concentrations up to 100 μM, as well as the serotonin (5-HT) receptor subtype 5-HT
3 (K
i = 240 nM)., Imetit reduces potassium-induced increases in histamine levels in isolated rat cerebral cortex slices (EC
50 = 2.8 nM). It increases scratching in mice (ED
50 = 0.9 μmol), an effect that is reduced by the H
3 receptor antagonist thioperamide .
Uses
Imetit dihydrobromide is a high affinity agonist at the histamine H3- and H4-receptors.
Definition
ChEBI: A hydrobromide salt obtained by reaction of imetit with two equivalents of hydrobromic acid. An extremely potent, high affinity agonist at H3 and H4 receptors (Ki values are 0.3 and 2.7 nM respectively). Induces sh
pe change in eosinophils with an EC50 of 25 nM. Centrally active following systemic administration.
Biological Activity
An extremely potent, high affinity agonist at H 3 and H 4 receptors (K i values are 0.3 and 2.7 nM respectively). Induces shape change in eosinophils with an EC 50 of 25 nM. Centrally active following systemic administration. Also available as part of the Histamine H 3 Receptor Tocriset™ .
Biochem/physiol Actions
Potent and selective H3 histamine receptor agonist.
References
[1] WILLIAM HOWSON . Two novel, potent and selective histamine H3 receptor agonists[J]. Bioorganic & Medicinal Chemistry Letters, 1992, 2 1: Pages 77-78. DOI:
10.1016/s0960-894x(00)80659-9[2] ROB LEURS. Evaluation of the receptor selectivity of the H3 receptor antagonists, iodophenpropit and thioperamide: an interaction with the 5-HT3 receptor revealed[J]. British Journal of Pharmacology, 1995, 116 4: 2315-2321. DOI:
10.1111/j.1476-5381.1995.tb15071.x[3] M GARBARG. S-[2-(4-imidazolyl)ethyl]isothiourea, a highly specific and potent histamine H3 receptor agonist.[J]. Journal of Pharmacology and Experimental Therapeutics, 1992, 263 1: 304-310.
[4] J K BELL J L R D S McQueen. Involvement of histamine H4 and H1 receptors in scratching induced by histamine receptor agonists in BalbC mice[J]. British Journal of Pharmacology, 2009, 142 2: 374-380. DOI:
10.1038/sj.bjp.0705754
