Angiotensin II, as part of the renin-angiotensin-aldosterone system, facilitates a sympathetic nervous system response mediated by the angiotensin II type 1 (AT1) receptor, causing vasoconstriction and subsequent increase in blood pressure. It potentiates noradrenaline release from sympathetic nerve terminals at the presynaptic level as well as amplifies the α-adrenoceptor-mediated vasoconstrictor response to endogenous noradrenaline. Angiotensin II receptor blockers (ARBs) are a major class of therapeutics designed to lower blood pressure and to provide cardiovascular protection. Eprosartan (mesylate) is a competitive AT1 receptor antagonist with IC50 values ranging from 1.4 – 3.9 nM and an elimination half-life of five to seven hours. Eprosartan is structurally distinct from other noncompetitive ARBs in that it does not contain a biphenyl, tetrazole moiety and blocks angiotensin II receptors on both sympathetic nerve terminals and blood vessels.
