Baroreceptor Reflex

What is the baroreceptor reflex?

Your baroreceptor reflex is a series of quick actions your body takes to keep your blood pressure in a normal range in response to an abrupt change in position (particularly, a seated/lying down position to a standing position). It’s the most important way your body regulates blood pressure during these short-term events. This is a relatively quick reflex that occurs over a span of a couple of heartbeats.

How does the baroreceptor reflex work?

When there’s a change in your blood pressure, your artery walls respond accordingly. For example, with increased blood volume, your blood vessel walls stretch. In certain parts of your body, baroreceptors, which are special nerve endings, can “sense” artery wall stretch. This message goes to your brain, which interprets it as adequate blood pressure. In the absence of this stretch, your brain responds accordingly to raise your blood pressure.

If you stand up quickly, your baroreceptors sense a lack of stretching of the artery walls. This message goes to your brain, which interprets it as inadequate blood pressure. Your brain tells your blood vessels to tighten up in order to raise your blood pressure. This is just one way your body can control your blood pressure.

Your body can also change your heart rate, how strongly your heart muscles contract and how much blood your heart’s pumping in response to a lack of stretching that the baroreceptors sense.

What does the baroreceptor reflex do?

Baroreceptors constantly monitor how much blood you have in your blood vessels and what the pressure is inside them. When your blood pressure needs to change, your baroreceptors tell your brain. Your brain signals your heart or blood vessels to take action that raises or lowers your blood pressure.

What triggers the baroreceptor reflex?

Any change in your body’s demand for blood can trigger your baroreceptor reflex. For example, your body may need to adjust your blood pressure when you:

• Change your body position, such as when you stand.
• See or experience something that frightens you.
• Switch from walking to running.

Where is the baroreceptor reflex located?

Your baroreceptor reflex doesn’t have one central location. Your baroreceptor reflex consists of several areas in your body that play a part in the reflex. You have baroreceptors in your heart, arteries in your neck and inside of your lungs. Information from those areas travels to your brain and all through your body’s nervous tissue.

What are the parts of the baroreceptor reflex?

Your baroreceptor reflex includes neurons and the nerve fibers that carry their messages about your blood pressure. It also includes the cardiovascular system that receives those messages and acts on that information.

These include:

• Baroreceptors in your carotid arteries and aortic arch.
• Baroreceptors in your heart chambers and the blood vessels of your lungs.
• Cranial nerves.
• Parasympathetic nervous system.
• Sympathetic nervous system.
• Arterioles.

What are the common conditions and disorders that affect the baroreceptor reflex?

Conditions that can affect how well your baroreceptor reflex works include:

• Parkinson’s disease.
• Broken heart syndrome (stress cardiomyopathy).
• Spinal cord injury.
• Type 1 or Type 2 diabetes.
• Postural orthostatic tachycardia syndrome.
• Lewy body dementia.

Tumors or neck surgery can damage the receptors that need to work well as part of your baroreceptor reflex.

Common signs or symptoms of conditions associated with dysfunctional baroreceptor reflex

These include:

• Unstable blood pressure.
• Too much or too little blood reaching your organs.
• Tachycardia.
• Inability to raise heart rate appropriately.

Common tests to check the health of the baroreceptor reflex

Ways to check the health of your baroreceptor reflex may include:

• Blood pressure monitoring, such as 24-hour ambulatory monitoring.
• Heart rate measurement.
• Valsalva maneuver.
• Blood tests.

Common treatments for the baroreceptor reflex

Medications to treat dysfunction of the baroreceptor reflex include:

• Midodrine.
• Droxidopa.
• Fludrocortisone.

Simple lifestyle changes/tips to keep the baroreceptor reflex healthy

To keep your blood pressure steady, you can talk with your healthcare provider about:

• Eating a healthy diet.
• Adjusting doses of drugs that are causing blood pressure issues.
• Trying an abdominal binder (a large belt you wrap tightly around your belly) to raise blood pressure if you have medical conditions associated with baroreflex dysfunction.
• Identifying and avoiding things that trigger high or low blood pressure if you have a medical condition that’s associated with baroreflex dysfunction (see list above).

A note from Cleveland Clinic

Your baroreceptor reflex works to regulate your blood pressure by responding quickly to things that make it too high or too low. You’re probably not aware of the changes your body makes when you stand or take off running, but your baroreceptor reflex is regulating your blood pressure. Talk to your healthcare provider if you’re having drops in blood pressure that lead to fainting. They can help you find the source of the issue.