Olmesartan

Olmesartan, an active metabolite of olmesartan medoxomil [O0510], is a selective AT₁ subtype angiotensin II receptor antagonist (“sartan”), such as candesartan [C2635], eprosartan [E1161], irbesartan [I0859], losartan [L0232], olmesartan [O0507], telmisartan [T2861] and valsartan [V0112].
Angiotensin II is formed from angiotensin I in a reaction catalyzed by angio-tensin converting angiotensin conversion enzyme (ACE), and can active two different receptors, AT₁ and AT₂, both of which are coupled to G-protein. The vasopressor actions of angiotensin II are mediated through AT₁ receptors. Olmesartan and sartans bind selectively to AT₁ receptor with almost no binding to AT₂ receptor in vascular smooth muscle. Therefore, olmesartan and sartans show blood pressure lowering effect. Recently, some combination agents with a calcium channel antagonist (e.g. amlodipine [A2353], azelnidipine [A2433]) are also used for the treatment of hypertension and cardiovascular disease. (The product is for research purpose only.)