What is the mechanism of action for angiotensin-converting enzyme (ACE) inhibitors in renal pharmacology?

What is the mechanism of action for angiotensin-converting enzyme (ACE) inhibitors in renal pharmacology?

• A. They block aldosterone secretion
• B. They cause vasodilation and reduce blood pressure
• C. They promote sodium retention
• D. They inhibit diuretic action

Answer: (B)

The mechanism of action for angiotensin-converting enzyme (ACE) inhibitors primarily involves causing vasodilation and reducing blood pressure. By inhibiting the enzyme that converts angiotensin I to angiotensin II, ACE inhibitors decrease the production of angiotensin II, which is a potent vasoconstrictor. This results in the dilation of blood vessels, leading to a reduction in systemic vascular resistance and subsequently lowering blood pressure. Additionally, by decreasing angiotensin II levels, ACE inhibitors also reduce the secretion of aldosterone, which normally promotes sodium and water retention. This further aids in decreasing blood volume and blood pressure. Therefore, the primary action of ACE inhibitors is to relax the blood vessels, which leads to improved blood flow and lower blood pressure, making option B the correct choice. The other options reflect processes that are either opposite to the action of ACE inhibitors or are not directly related to their primary mechanism. For instance, while aldosterone secretion is affected by ACE inhibitors, they do not directly block its secretion; rather, they lower levels of angiotensin II, which in turn decreases aldosterone production. Similarly, promoting sodium retention and inhibiting diuretic action are contrary to the effects of ACE inhibitors, as these medications are used

The mechanism of action for angiotensin-converting enzyme (ACE) inhibitors primarily involves causing vasodilation and reducing blood pressure. By inhibiting the enzyme that converts angiotensin I to angiotensin II, ACE inhibitors decrease the production of angiotensin II, which is a potent vasoconstrictor. This results in the dilation of blood vessels, leading to a reduction in systemic vascular resistance and subsequently lowering blood pressure.

Additionally, by decreasing angiotensin II levels, ACE inhibitors also reduce the secretion of aldosterone, which normally promotes sodium and water retention. This further aids in decreasing blood volume and blood pressure. Therefore, the primary action of ACE inhibitors is to relax the blood vessels, which leads to improved blood flow and lower blood pressure, making option B the correct choice.

The other options reflect processes that are either opposite to the action of ACE inhibitors or are not directly related to their primary mechanism. For instance, while aldosterone secretion is affected by ACE inhibitors, they do not directly block its secretion; rather, they lower levels of angiotensin II, which in turn decreases aldosterone production. Similarly, promoting sodium retention and inhibiting diuretic action are contrary to the effects of ACE inhibitors, as these medications are used