Regulation of Mean Arterial Pressure (MAP) – Key Vocabulary

20 vocabulary flashcards covering major terms related to blood-pressure regulation from the lecture.

Mean Arterial Pressure (MAP)

The average pressure in the aorta/systemic arteries; primary clinical blood-pressure value that sets the systemic pressure gradient.

Cardiac Output (CO)

The volume of blood ejected by the left ventricle each minute; equal to stroke volume × heart rate.

Total Peripheral Resistance (TPR)

The summed resistance to blood flow offered by all systemic blood vessels.

Stroke Volume (SV)

The amount of blood pumped out of one ventricle with every heartbeat.

Heart Rate (HR)

The number of heartbeats per minute.

Poiseuille’s Law

Flow = ΔPressure ÷ Resistance; foundational equation relating flow, pressure gradient, and resistance.

Aortic Pressure

Blood pressure within the aorta that establishes the systemic pressure gradient for blood flow.

Systemic Circuit

Circulatory pathway that carries oxygenated blood from the left heart to the body and returns deoxygenated blood to the right heart.

Frank-Starling Effect

Intrinsic mechanism in which increased ventricular filling stretches myocardium and raises stroke volume.

Vasoconstriction

Narrowing of blood vessel diameter, increasing resistance and elevating blood pressure.

Vasodilation

Widening of blood vessel diameter, decreasing resistance and lowering blood pressure.

Hypertension

Abnormally high arterial blood pressure above the set point.

Hypotension

Abnormally low arterial blood pressure below the set point.

Heart Failure

Pathological weakening of the myocardium that reduces stroke volume and leads to low MAP.

Short-term Regulation of MAP

Fast (seconds–minutes) adjustments via changes in cardiac output and vessel diameter under autonomic control.

Long-term Regulation of MAP

Slow (hours–days) adjustments via renal control of blood volume and behavioral fluid intake.

Behavioral Adjustments

Thirst-driven fluid intake that modifies blood volume to support long-term MAP regulation.

Blood Volume

Total quantity of blood in circulation; higher volume raises MAP, lower volume reduces MAP.

Contractility

Force of ventricular contraction independent of preload; sympathetic stimulation increases it to boost stroke volume.

Pressure Gradient

Difference in pressure between two points that drives blood flow; in systemic circulation mainly between the aorta and right atrium.