What is the purpose of reactive hyperemia?

Reactive hyperemia serves as a physiological response to a temporary disruption in blood flow. When tissue experiences ischemia, or a brief lack of blood supply, the body's compensatory mechanism comes into play once perfusion is restored. This mechanism is characterized by vasodilation, which leads to an increase in blood flow to the affected area.

During reactive hyperemia, the vessels respond to accumulated metabolites (like carbon dioxide and adenosine) that build up during ischemic conditions. These metabolites signal arterioles to dilate, which allows for an influx of oxygen-rich blood once the restriction is lifted. This process not only restores normal blood flow but also aids in the removal of waste products and helps with tissue recovery.

In this context, the option related to inducing ischemia and vasodilation signifies that, despite the period of reduced blood flow, the restoration phase involves vasodilation to increase blood supply to the area, effectively addressing the initial lack of perfusion.