Betahistine

Betahistine is a histamine analog and H1 receptor agonist that serves as a vasodilator. It is used in MENIERE DISEASE and in vascular headaches but may exacerbate bronchial asthma and peptic ulcers. Betahistine dihydrochloride is an anti-vertigo drug. It is commonly prescribed for balance disorders or to alleviate vertigo symptoms associated with Ménière's disease. (In Vitro) :Betahistine (0-10 μM) inhibits [125I]iodoproxyfan binding to membranes of CHO (rH3 (445) R) and CHO (hH3 (445) R) cells with IC50 values of 1.9 μM and 3.3 μM, respectively. Lead to Ki values of 1.4 μM and 2.5 μM, respectively.Betahistine (0-10 μM) has a regulating function on cAMP formation in CHO (rH3 (445) R), CHO (rH3 (413) R), and CHO (hH3 (445) R) cells. At low concentrations, betahistine behaves an apparent inverse agonist, and progressively enhances cAMP formation with EC50 values of 0.1 nM, 0.05 nM and 0.3 nM, respectively. In contrast, at concentrations higher than 10 nM, betahistine inhibits cAMP formation with an EC50 value of 0.1 μM in CHO (rH3 (445) R) and full agonist activity. (In Vivo) :Betahistine (intraperitoneal or oral administration; 0.1-30 mg/kg; single dose) with acute administration has increased tele-methylhistamine (t-MeHA) levels with an ED50 of 0.4 mg/kg, indicating the inverse agonism. Besides, after acute oral administration, it increases t-MeHA levels with an ED50 of 2 mg/kg in male Swissmice.Betahistine (oral adminstration; 1 and 5 mg/kg; daily for 3 weeks) attenuates the severity of arthritis and reduces the levels of pro-inflammatory cytokines in the paw tissues of CIA mice.