What is the primary mechanism of action of ACE inhibitors?

The primary mechanism of action of ACE inhibitors is that they inhibit the conversion of angiotensin I to angiotensin II. This fundamental action leads to a cascade of effects, including vasodilation, which is the widening of blood vessels. By preventing the formation of angiotensin II, ACE inhibitors effectively reduce the potent vasoconstriction that this peptide typically induces.

As a consequence of decreased levels of angiotensin II, there is a reduction in blood pressure since vasodilation decreases vascular resistance. Additionally, the inhibition of angiotensin II also reduces the release of aldosterone, leading to decreased sodium and water retention, contributing further to lower blood pressure and a reduced blood volume.

This mechanism is crucial in managing conditions such as hypertension and heart failure, where excessive vasoconstriction and fluid retention can exacerbate the patient's condition. The specific blockade of the angiotensin-converting enzyme therefore underscores the therapeutic utility of these medications in cardiovascular management.