American Association of Critical-Care Nurses (AACN) Certification Practice Test

Which class of medications is used for treating both erectile dysfunction and pulmonary hypertension?

1. Beta-blockers

2. Phosphodiesterase inhibitors

3. Angiotensin receptor blockers

4. Calcium channel blockers

The correct answer is: Phosphodiesterase inhibitors

The correct answer is phosphodiesterase inhibitors. This class of medications works by blocking the enzyme phosphodiesterase type 5 (PDE5), which leads to increased levels of cyclic guanosine monophosphate (cGMP). Elevated cGMP levels promote relaxation of smooth muscle and dilation of blood vessels, particularly in the lungs and erectile tissues. This mechanism is significant for two conditions: erectile dysfunction, as the increased blood flow to the penis enhances the ability to achieve and maintain an erection; and pulmonary hypertension, where the dilation of pulmonary blood vessels helps to lower pulmonary arterial pressure and improve exercise capacity in affected individuals. In contrast, beta-blockers primarily affect heart rate and blood pressure but do not specifically target the mechanisms involved in erectile function or pulmonary vessel dilation. Angiotensin receptor blockers focus on the renin-angiotensin system but aren’t used to manage erectile dysfunction. Calcium channel blockers primarily work by relaxing blood vessels to lower blood pressure but lack the specific action on erectile dysfunction treatment or pulmonary hypertension management associated with phosphodiesterase inhibitors.