Which of the Following is True of Vasoconstriction

Question

Which of the following is true of vasoconstriction?
A) Caused by parasympathetic nerve stimulation
B) Increases afterload
C) Caused by vagal discharge
D) Generally accompanied by arteriolar dilation

Accepted Answer

Vasoconstriction is the narrowing of blood vessels due to contraction of their smooth muscle walls, which increases resistance to blood flow and raises blood pressure. This increased resistance to blood flow leads to an increase in afterload. Vasoconstriction is typically caused by sympathetic nerve stimulation, not parasympathetic or vagal discharge. Additionally, vasoconstriction is accompanied by arteriolar constriction, not dilation.