Question

Forearm blood flow in response to acetylcholine is reduced in a patient with high cholesterol. An increase in which of the following most likely contributes to this impaired vasodilatory response to acetylcholine in this patient?

a Nitric oxide
b Endothelial hyperpolarization
c Prostacyclin
d Adenosine
e Endothelial-1

Answer 1

The impaired vasodilatory response to acetylcholine in a patient with high cholesterol is likely due to a reduced production of nitric oxide, which is essential for vasodilation.

Step-by-step explanation:

In the context of cardiovascular physiology, the reduction of forearm blood flow in response to acetylcholine in a patient with high cholesterol is likely due to impaired production or availability of nitric oxide (NO). Normally, acetylcholine stimulates endothelial cells to produce NO, which diffuses to adjacent vascular smooth muscle cells where it triggers a cascade of events resulting in vasodilation. In individuals with high cholesterol, the endothelial function can become compromised, leading to a reduced ability to produce nitric oxide, therefore impairing vasodilation. This is why the answer is (a) Nitric oxide, as increasing NO availability would likely improve the impaired vasodilatory response to acetylcholine.