New method to treat high blood pressure

Carotid body seems to be a major culprit in the development, regulation of high blood pressure. (Reuters)

In a breakthrough, scientists have found that removing the grain-sized carotid body - one of the tiniest organs in the human body - may treat high blood pressure, potentially revolutionising treatment for the world's biggest silent killer.

The carotid body - a small nodule (no larger than a rice grain) found on the side of each carotid artery - appears to be a major culprit in the development and regulation of high blood pressure.

University of Bristol researchers found that by removing the carotid body connection to the brain in rodents with high blood pressure, blood pressure fell and remained low.

"We knew that these tiny organs behaved differently in conditions of hypertension but had absolutely no idea that they contributed so massively to the generation of high blood pressure; this is really most exciting," said Professor Julian Paton, from Bristol's School of Physiology and Pharmacology.

Normally, the carotid body acts to regulate the amount of oxygen and carbon-dioxide in the blood. They are stimulated when oxygen levels fall in your blood as occurs when you hold your breath.

This causes a dramatic increase in breathing and blood pressure until blood oxygen levels are restored. This response comes about through a nervous connection between the carotid body and the brain.

"Despite its small size the carotid body has the highest blood flow of any organ in the body. Its influence on blood pressure likely reflects the priority of protecting the brain with enough blood flow," Paton said.

The discovery has led to a human clinical trial at the Bristol Heart Institute the results of which are expected at the end of the year.

The study was published in journal Nature Communications.