Baroreceptor reflex

Definition

The baroreceptor reflex is a homeostatic mechanism that helps maintain blood pressure at nearly constant levels. It involves receptors located in the walls of blood vessels that detect changes in blood pressure and send signals to the central nervous system to adjust heart rate and vascular resistance.

5 Must Know Facts For Your Next Test

1. Baroreceptors are primarily located in the carotid sinuses and aortic arch.
2. When blood pressure rises, baroreceptors increase their firing rate, signaling the brain to lower heart rate and dilate blood vessels.
3. When blood pressure drops, baroreceptors decrease their firing rate, prompting the brain to increase heart rate and constrict blood vessels.
4. The baroreceptor reflex is a negative feedback loop essential for short-term regulation of blood pressure.
5. Pharmacological agents like beta-blockers can influence the baroreceptor reflex by altering heart rate responsiveness.

Review Questions

• Where are the primary locations of baroreceptors in the cardiovascular system?
• How does the baroreceptor reflex respond to an increase in blood pressure?
• Why is the baroreceptor reflex considered a negative feedback loop?

Related terms

Carotid Sinus: A dilation located at the base of the internal carotid artery containing baroreceptors that monitor arterial blood pressure.

Aortic Arch: The part of the main artery (aorta) that bends between its ascending and descending portions; contains baroreceptors involved in blood pressure regulation.

Beta-Blocker: A class of drugs that reduce heart rate, decrease cardiac output, and can affect how the body responds to baroreceptor signals.