By Kate Kelland /London

Scientists experimenting with rats have found that de-activating certain nerves in the neck can effectively treat high blood pressure - a discovery that could be an advance in tackling one of the world’s biggest silent killers.

Researchers at Britain’s Bristol University found that in rats with high blood pressure, when they removed nerve links between the brain and the carotid body - a nodule about the size of a grain of rice on the side of each carotid artery - the animals’ blood pressure fell and remained low.

The researchers results, published in the journal Nature Communications yesterday, have already led the team on to conduct a small human trial of the technique, with results expected at the end of this year. 

Hypertension, or high blood pressure, is referred to by the World Health Organisation (WHO) as one of the world’s biggest silent killers because most people who have it can’t feel or see it.

It affects around one in three people worldwide and can cause stroke, heart attacks and kidney failure.

After diagnosis, treatment of high blood pressure needs to be lifelong and many patients are able to manage their condition with anti-hypertension drugs. But experts say that for around 1 in 50 of them, medication does not help.  

Julian Paton, who led this latest study at Bristol’s school of physiology and pharmacology, said while scientists already knew of a link between the carotid organs and hypertension, until now t4hey “had absolutely no idea that they contributed so massively to the generation of high blood pressure.”

Tim Chico, as consultant cardiologist at the University of Sheffield who was not directly involved in the research, described the technique as “exciting and innovative” but cautioned that more work was needed to assess its effectiveness and safety before it could be considered for use in patients.

Normally, Paton explained, the carotid body acts to regulate the amount of oxygen and carbon dioxide in the blood.

It is stimulated when oxygen levels fall in the blood - such as when someone is holding their breath. This then causes a dramatic increase in breathing and blood pressure until blood oxygen levels are restored.

Having established that this response comes about through a nerve connection between the carotid body and the brain, Paton’s team decided to block the nerve endings in the neck and found that it swiftly brought their blood pressure down.  

Jeremy Pearson, associate medical director at the British Heart Foundation, which part-funded this latest research, said all eyes are now on the human trial aiming to find out whether the treatment might work in people with high blood pressure who don’t get better with current drugs.

Tony Heagerty, a professor of medicine at Manchester University who was not involved in the study, said it was an interesting development which could “potentially avoid the use of drugs which have to be taken on a daily basis for many years.” - Reuters

 

Doctors concerned as heart drug research loses momentum

The hunt for new heart drugs is losing momentum as resources are switched to other areas, notably cancer research, where investors get a better bang for their buck. Cardiologists fear the fight against heart disease could stall as a result, following major advances in recent decades marked by the advent of drugs to fight cholesterol, lower blood pressure and prevent dangerous blood clots.

The disparity between advances in cancer and heart medicines is already stark. Since the start of 2012, 17 new drugs been approved by the US Food and Drug Administration for cancer compared with just three for heart disease.  “There is a clear move of R&D from cardiovascular to cancer and other areas,” said Michel Komajda, a heart specialist at Pitie-Salpetriere Hospital in Paris and a former president of the European Society of Cardiology (ESC).  Komajda, like many of his colleagues gathered at the annual ESC congress this week in Amsterdam, is worried.

Despite the giant manufacturers’ stands touting heart medicines at this week’s meeting of some 30,000 doctors, investment in cardiovascular medicine is ebbing - prompting calls for an urgent rebalancing of research priorities.

“There is a view among some that because we have already made a lot of progress in cardiovascular medicine then maybe it doesn’t make sense to invest any more,” Komajda said.