DBH

Class

Dopamine β-hydroxylase inhibitor

Dopamine β-hydroxylase (DBH) is an enzyme located inside the storage vesicles of sympathetic nerve terminals and the adrenal medulla. It catalyzes the conversion of dopamine, a neurotransmitter, into norepinephrine (also called noradrenaline), the principal chemical messenger of the sympathetic nervous system, which governs functions such as heart rate, blood vessel tone, and blood pressure. Inhibiting DBH reduces the production of norepinephrine while increasing the relative amount of dopamine available for release. This shift in the balance between the two neurotransmitters can lower excessive sympathetic nervous system activity, which is relevant in conditions such as hypertension and heart failure, where chronically elevated norepinephrine signaling contributes to disease progression. Because dopamine itself has some vasodilating and natriuretic (sodium-excreting) properties, the resulting neurochemical profile after DBH inhibition may be doubly favorable in cardiovascular disease: less norepinephrine-driven vasoconstriction and stress on the heart, alongside more dopamine-mediated effects that can support blood vessel relaxation and kidney sodium handling. DBH inhibition has also been explored for conditions linked to excessive sympathetic drive or catecholamine dysregulation more broadly. As an enzyme rather than a receptor, DBH offers a way to modulate the entire downstream cascade of norepinephrine signaling at its biosynthetic source, rather than blocking one specific receptor subtype.