Rauwolfia serpentina root

Reserpine is an adrenergic blocking agent used to treat mild to moderate hypertension via the disruption of norepinephrine vesicular storage. The antihypertensive actions of Reserpine are a result of its ability to deplete catecholamines from peripheral sympathetic nerve endings. These substances are normally involved in controlling heart rate, the work of cardiac contraction and peripheral resistance. Reserpine depletes brain (depression) and peripheral (PPH) noradrenaline (NA) storage sites, guanethidine depleted NA storage via blockade of reuptake.

This agent binds and inhibits catecholamine pump on the storage vesicles in central and peripheral adrenergic neurons, thereby inhibiting the uptake of norepinephrine, dopamine serotonin into presynaptic storage vesicles. This results in catecholamines and serotonin lingering in the cytoplasm where they are destroyed by intraneuronal monoamine oxidase, thereby causing the depletion of catecholamine and serotonin stores in central and peripheral nerve terminals. Depletion results in a lack of active transmitter discharge from nerve endings upon nerve depolarization, and consequently leads to a decreased heart rate and decreased arterial blood pressure as well as sedative effects.