Blood Pressure Basics

Blood Pressure and Baroreceptors

• Blood pressure is the force of blood pushing against the walls of arteries as the heart pumps blood.
• Baroreceptors play a crucial role in the autonomic nervous system, helping to regulate blood pressure by sensing changes in arterial pressure.

Location and Function of Baroreceptors

• Baroreceptors are located in the walls of certain arteries, particularly in the carotid sinus and aortic arch.
• The primary function of baroreceptors is to detect changes in arterial pressure and send signals to the brain, which then responds to maintain blood pressure within a normal range.

Pressor Reflexes

• Pressor reflexes are a type of reflex that helps to increase blood pressure when it falls, and decrease blood pressure when it rises.
• The function of pressor reflexes is to maintain blood pressure homeostasis by stimulating the heart to beat faster or slower, and constricting or dilating blood vessels as needed.

Baroreceptors and the Autonomic Nervous System

• Baroreceptors send afferent nerve fibers to the medulla oblongata in the brain, which is part of the autonomic nervous system.
• The autonomic nervous system processes the signals from baroreceptors and responds by stimulating the heart and blood vessels to make necessary changes to maintain blood pressure.

Effects of Arterial Pressure Rise

• When arterial pressure rises, blood vessels constrict or vasoconstrict, which decreases blood flow to certain areas of the body.
• The heart rate slows down in response to a rise in arterial pressure, as the body does not need to pump as much blood to maintain the increased pressure.