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H3 Antagonists (h3 + antagonist)

Distribution by Scientific Domains

Medical Sciences	50%

Selected Abstracts

A New Class of Potent Non-imidazole H3 Antagonists: 2-Aminoethylbenzofurans.

CHEMINFORM, Issue 23 2004
Marlon Cowart
Abstract For Abstract see ChemInform Abstract in Full Text. [source]

Targeting of the central histaminergic system for treatment of obesity and associated metabolic disorders

DRUG DEVELOPMENT RESEARCH, Issue 8 2006
Kjell Malmlöf
Abstract There is currently a need for effective pharmacological therapies for treatment of obesity. In this communication, the involvement of the neurotransmitter histamine in the regulation of food intake is reviewed, together with results obtained in animals with pharmacologically increased brain histamine levels. A survey of the literature reveals that histaminergic circuits, arising from nerve cell bodies in the tuberomammillary nucleus and projecting into the paraventricular nucleus, the arcuate nucleus, and the ventromedial hypothalamus, are strongly involved in regulation of food intake and possibly also energy expenditure. Current literature also suggests the histaminergic circuits connect to other neuronal pathways involved in the regulation of energy balance and body weight. Studies performed in rodents demonstrate that H3 receptor antagonists increase hypothalamic histamine and decrease food intake, which result in decreased body weight. Lipid oxidation is increased and, at higher doses, body fat is also decreased. These changes are associated with lower circulating levels of insulin during an oral glucose challenge suggesting an increase in insulin sensitivity. The effects on food intake have also been confirmed in pigs and rhesus monkeys. It can thus be concluded that results obtained with H3 antagonist in animals warrant future clinical studies to evaluate whether this principle is effective in the treatment of human obesity. Drug Dev. Res. 67:651,665, 2006. © 2006 Wiley-Liss, Inc. [source]

Corrigendum to acute wake-promoting actions of JNJ-5207852, a novel, diamine-based H3 antagonist

BRITISH JOURNAL OF PHARMACOLOGY, Issue 1 2005
A J Barbier
No abstract is available for this article. [source]

Histamine H3 receptor-mediated impairment of contextual fear conditioning and in-vivo inhibition of cholinergic transmission in the rat basolateral amygdala

EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 9 2001
M. Beatrice Passani
Abstract We investigated the effects of agents acting at histamine receptors on both, spontaneous release of ACh from the basolateral amygdala (BLA) of freely moving rats, and fear conditioning. Extensive evidence suggests that the effects of histamine on cognition might be explained by the modulation of cholinergic systems. Using the microdialysis technique in freely moving rats, we demonstrated that perfusion of the BLA with histaminergic compounds modulates the spontaneous release of ACh. The addition of 100 mm KCl to the perfusion medium strongly stimulated ACh release, whereas, 0.5 µm tetrodotoxin (TTX) inhibited spontaneous ACh release by more than 50%. Histaminergic H3 antagonists (ciproxifan, clobenpropit and thioperamide), directly administered to the BLA, decreased ACh spontaneous release, an effect fully antagonized by the simultaneous perfusion of the BLA with cimetidine, an H2 antagonist. Local administration of cimetidine alone increased ACh spontaneous release slightly, but significantly. Conversely, the administration of H1 antagonists failed to alter ACh spontaneous release. Rats receiving intra-BLA, bilateral injections of the H3 antagonists at doses similar to those inhibiting ACh spontaneous release, immediately after contextual fear conditioning, showed memory consolidation impairment of contextual fear conditioning. Post-training, bilateral injections of 50 µg scopolamine also had an adverse effect on memory retention. These observations provide the first evidence that histamine receptors are involved in the modulation of cholinergic tone in the amygdala and in the consolidation of fear conditioning. [source]

Histamine-3 receptor antagonists reduce superoxide anion generation and lipid peroxidation in rat brain homogenates

JOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 6 2005
H. E. Badenhorst
Using a cyanide model to induce neurotoxic effects in rat brain homogenates, we examined the neuroprotective properties of three H3 antagonists, namely clobenpropit, thioperamide and impentamine, and compared them to aspirin, a known neuroprotective agent. Superoxide anion levels and malondialdehyde concentration were assessed using the nitroblue tetrazolium and lipid peroxidation assays. Clobenpropit and thioperamide significantly reduced superoxide anion generation and lipid peroxidation. Impentamine reduced lipid peroxidation at all concentrations used, but only reduced superoxide anion generation at a concentration of 1 mM. In the lipid peroxidation assay, all the drugs compared favourably to aspirin. This study demonstrates the potential of these agents to be neuroprotective by exerting antioxidant effects. [source]