Gothenburg [Sweden], February 15 (ANI): It is natural for people to become stressed in their daily work, but sometimes this stress can lead to a rise in blood pressure. New research has shown that smaller daily increases in blood pressure due to short-term stressors can be linked to an area in the brain that controls conscious and learned motor skills.
This discovery, presented by researchers from the University of Gothenburg, paved the way for a chance to influence blood pressure increases and in the long run prevent high blood pressure. The study was published in ‘Scientific Reports’.
In about half of all people with high blood pressure – persistent high blood pressure (BP) – there is no known cause. A reasonable theory, however, is that hypertension may be the result of a long period with many recurring BP peaks. Hundreds or thousands of micro-stress events can occur daily – the phone rings, a car horn sounds in the street – with BP increases every time as a result.
For almost 20 years now, a research group at the University of Gothenburg has investigated how this type of micro-stress affects nerve signals to our muscles and the flow (perfusion) of blood in their vessels (muscle vessels). In half of the more than 150 men included in the group’s studies so far, the pattern in their reaction system leads to BP peaks, while in the other half, the reactions that take place in their bodies do not lead to any change in BP.
For the study, 20 men aged 19-45 years were examined. The experiment was to trigger a response in the nervous system with unexpected electric shocks that mimic the sudden and / or stressful stimuli that we are exposed to daily. The researchers combined two measurement methods. In one, a traditional research technique called microneurography, very thin needle electrodes are used to examine the signaling in nerve fibers (especially muscle sympathetic nerve activity, MSNA) directed to the muscle’s vascular bed (blood vessels). The other was a modern brain imaging technique known as magnetoencephalography (MEG).
For the first time, researchers were able to link the increased sensitivity to micro-stress to a reflex-like signal in the brain. The brain region (“the Rolandian region”) that activated the signal controlled several conscious brain functions. This finding opened up the question of whether the BP peaks can be learned and therefore also, with training, can be eliminated.
“We see a surprisingly strong connection between the peripheral autonomic vascular reaction, which takes place subconsciously, and a reaction pattern – one that was already well known – in a part of the brain where emotional impressions and motor skills undergo a conscious interpretation. This raises questions about how independent the “autonomic nervous system”, as it is called, really works “, says Mikael Elam, professor of clinical neurophysiology at Sahlgrenska Academy, University of Gothenburg.
The idea that the discovery could be used to prevent high blood pressure was not unrealistic, but much research was needed.
“If we can develop ways to increase the signal-to-noise ratio, it may be possible in the future to extract the relevant brain signals from a standard electroencephalogram. [EEG], which is available in all Swedish hospitals today. This would allow us to identify at an early stage people who react with blood pressure spikes before they develop high blood pressure. Many other opportunities for preventive measures and research would then follow, says Justin Schneiderman, senior lecturer in experimental multimodal neuroimaging at Sahlgrenska Academy, University of Gothenburg.
Interestingly, our environment seemed to be more important than our genetic code when it came to the reaction pattern we developed, and thus whether we experience many daily blood pressure spikes or not. An earlier study by the research group on identical twins showed that the basic activity in the twins’ vascular-regulating autonomic nervous system was very similar, while their stress-triggered reactions diverged.
“One can speculate that many people today have learned to suppress the primitive fight-or-flight response, as it is not so relevant in modern society. It is an impulse that prepares us for action, by reducing activity in “The vasoconstrictor nerve, thereby increasing blood flow to the muscles. In terms of long-term health consequences, it may be beneficial to preserve the old flight-or-fight impulse in response to sudden stressors,” Elam thought.
The research group hoped to facilitate studies at the population level and follow large groups of people for a long period. This would allow examination of whether individuals with reaction patterns that cause many peaks in blood pressure during the day are really at increased risk of developing hypertension later in life and whether it is possible to influence this reaction pattern. (ANI)