What happens to diastolic blood pressure when arterioles are dilated?

When arterioles are dilated, diastolic blood pressure typically decreases. This reduction occurs because the dilation of arterioles leads to increased vascular capacitance and a decrease in vascular resistance in the systemic circulation. As resistance decreases, blood is able to flow more freely through the dilated vessels, which in turn lowers the diastolic pressure recorded in the arteries.

Diastolic blood pressure is influenced primarily by the resistance the blood encounters as it flows through the arteries during the relaxation phase of the heart cycle. With dilated arterioles, there is less resistance, resulting in a lower pressure during diastole. Understanding this relationship is crucial in managing conditions that relate to blood pressure regulation, as well as in recognizing the physiological responses to various medications or therapeutic interventions that cause vasodilation.