Brain Region That Controls Breathing May Trigger High Blood Pressure

Hidden Brain Circuit Linked to Hypertension

Scientists have uncovered a surprising culprit behind some cases of high blood pressure: a small region in the brainstem that normally controls breathing . This area, called the lateral parafacial region, is located in the brainstem, the oldest part of the brain responsible for automatic functions like breathing, digestion, and heart rate .

The discovery emerged from research conducted by teams at the University of São Paulo in Brazil and the University of Auckland in New Zealand. "The lateral parafacial region is recruited into action causing us to exhale during a laugh, exercise or coughing," says lead researcher Professor Julian Paton. "These exhalations are what we call 'forced' and driven by our powerful abdominal muscles."

What makes this finding remarkable is the dual role this brain region appears to play. This area, which kicks in during forceful exhalations like coughing, laughing, or exercise, also appears to activate nerves that tighten blood vessels—raising blood pressure . When researchers switched off this region in experiments, blood pressure dropped back to normal, suggesting it plays a direct role in hypertension .

Why Current Treatments Fall Short

This research may help explain a persistent medical puzzle. Around 40 percent by some estimates still have uncontrolled blood pressure despite taking anti-hypertensive medications . Around 50 percent of patients with hypertension have a neurogenic component , suggesting the brain and nervous system play larger roles than previously understood.

"We discovered that, in conditions of high blood pressure, the lateral parafacial region is activated and, when our team inactivated this region, blood pressure fell to normal levels," says physiologist Julian Paton . The experiments, conducted in rats, showed that pFL neurons weren't just helping with breathing, but also acting to constrict blood vessels .

The findings also offer new insights into why people with sleep apnea face higher hypertension risks. The findings published here also go some way to explaining why people who have sleep apnea – problems breathing in the night – also have a higher risk of high blood pressure. It's that connection between breathing and blood flow again .

A Safer Treatment Approach

Traditional brain-targeted medications pose significant challenges because they affect the entire brain rather than specific regions. However, researchers have identified a potentially safer treatment pathway. Carotid bodies are clusters of cells that act like tiny sensors in the neck, and can influence pFL neurons from outside the brain .

"Our goal is to target the carotid bodies, and we are importing a new drug that is being repurposed by us to quench carotid body activity and inactivate 'remotely' the lateral parafacial region safely, i.e., without needing to use a drug that penetrates the brain" , explains Paton.

This approach could prove especially valuable for sleep apnea patients, since carotid bodies are activated in these patients when they stop breathing at night . By targeting these neck sensors rather than the brain directly, doctors might achieve better blood pressure control with fewer side effects.

Breathing Patterns as Medical Clues

The research suggests that monitoring breathing patterns could become a valuable diagnostic tool. These findings suggest that certain breathing patterns, particularly those involving strong abdominal muscle use, can contribute to elevated blood pressure. Identifying abdominal breathing in people with hypertension may help pinpoint the cause and guide more targeted treatment .

This discovery represents a fundamental shift in understanding hypertension. The bigger point is that high blood pressure is not always just about salt, weight or blood vessels themselves. In some people, the brain may be playing a bigger part than previously thought .

While these findings require further human studies before becoming standard treatment, they open promising new avenues for the millions worldwide struggling with uncontrolled hypertension. The research, published in Circulation Research, suggests that future blood pressure management may focus as much on calming overactive brain circuits as on traditional cardiovascular approaches.