In a paper published today by Neuroreport, researchers at Oxford University and Imperial College London report that they have found the exact area of the brain that controls blood pressure and how to make use of it.
A team of neurosurgeons and physiologists have found that they can make patients’ blood pressure increase or decrease by stimulating with electrodes very specific regions of the brain.
Deep brain stimulation - placing very thin electrodes onto exact locations in the brain - is already used to relieve pain or to help Parkinsons’ sufferers to move better.
Fifteen patients having the operation to implant electrodes for pain control agreed to take part in a study to see whether stimulating another location in the brain could alter blood pressure.
It was found that blood pressure could indeed be changed, and that it could be raised or lowered very precisely by stimulating different, very specific parts of the brain. This potentially offers a cure to sufferers of high blood pressure that does not depend on taking drugs long-term.
Blood is carried from the heart to all parts of your body in vessels called arteries. Blood pressure is the force of the blood pushing against the walls of the arteries. Each time the heart beats (about 60-70 times a minute at rest), it pumps out blood into the arteries. Your blood pressure is at its highest when the heart beats, pumping the blood. This is called systolic pressure. When the heart is at rest, between beats, your blood pressure falls. This is the diastolic pressure.
Blood pressure is always given as these two numbers, the systolic and diastolic pressures. Both are important. Usually they are written one above or before the other, such as 120/80 mmHg. The top number is the systolic and the bottom the diastolic. When the two measurements are written down, the systolic pressure is the first or top number, and the diastolic pressure is the second or bottom number (for example, 120/80). If your blood pressure is 120/80, you say that it is “120 over 80.”
As the electrodes can be switched on and off, another condition that could potentially be treated using this method is ‘postural hypotension’, a condition where a patient’s blood pressure falls uncontrollably upon standing up.
Mr Alexander Green, lead author of the paper, said: ‘Obviously, as this is brain surgery, we have to proceed with great caution: it would initially only be warranted in those patients for whom drug treatments just aren’t working. However, other research groups are working on less invasive methods of stimulating exact locations in the brain, for example using nanotechnology, and if this becomes available then the treatment would be attractive to a much larger number of people.’
Revision date: June 18, 2011
Last revised: by Janet A. Staessen, MD, PhD