Description_x000D_ Packaging_x000D_ 5, 25 mg in glass bottle_x000D_ Biochem/physiol Actions_x000D_ A-331440 dihydrochloride is a non-imidazole H3 histamine receptor antagonist. Presynaptic histamine H(3) receptors regulate release of histamine and other neurotransmitters, and histamine H(3) receptor antagonists enhance neurotransmitter release. A-331440 is a histamine H(3) receptor antagonist, which binds potently and selectively to both human and rat histamine H(3) receptors (K(i)=25 nM). Mice on a high-fat diet (45 kcal % lard) prior to 28-day oral b.i.d. dosing for measurement of obesity-related parameters. A-331440 administered at 0.5 mg/kg had no significant effect on weight, whereas 5 mg/kg decreased weight comparably to dexfenfluramine (10 mg/kg). A-331440 administered at 15 mg/kg reduced weight to a level comparable to mice on the low-fat diet. The two higher doses reduced body fat and the highest dose also normalized an insulin tolerance test. Both data shows that the histamine H(3) receptor antagonist, A-331440, has potential as an antiobesity agent._x000D_ Features and Benefits_x000D_ This compound is featured on the Histamine Receptors page of the Handbook of Receptor Classification and Signal Transduction. To browse other handbook pages, click here._x000D_ This compound was developed by Abbott. To browse the list of other pharma-developed compounds and Approved Drugs/Drug Candidates, click here.