A new study that has been published in the journal Biological Psychiatry shows that the cells that are involved in the fight against infections (T cells) are also involved in the increase of blood pressure. Tests were conducted on laboratory mice and have shown that after being subjected to psychological stress, the rise of blood pressure is affected by T cells. Test results also show that the effects that chronic stress has on the cardiovascular health of patients be caused by the presence of our immune system.
“Chronic stress has long been known to have harmful effects on the immune system as well as being a risk factor for hypertension,” says lead author Paul Marvar from the Emory University School of Medicine from the United States of America. Marvar also said that the main goal of the study was to determine whether or not T cells have an important role in stress-dependent hypertension. Marvar worked in collaboration with Dr. David Harrison, who later moved from the Emory University and with Dr. Kerry Ressler, professor of psychiatry and behavioral sciences.
For the current research, scientists used laboratory mice that were subjected to psychological stress through the confinement in an enclosed space for one hour. This was done two times a day for a week and resulted in the increase of blood pressure with almost 10 mm Hg, from around 115 to 125 mm Hg.
Along with normal mice, another batch of mice were tested. This second batch only included mice that genetically lacked T cells. Researchers observed that the second batch of mice did not show an increase in blood pressure after being subjected to the same tests. However, after injecting T cells into the mice, scientists observed that blood pressure became sensitive to stress.
In an earlier study, Dr. David Harrison and his team revealed the fact that the process involved in the increase of blood pressure requires T cells and the blood pressure regulating hormone, angiotensin.
The lead author of the study also notes that there are numerous recent studies which suggest that current medication used in the treatment and control of blood pressure could also help reduce stress and anxiety.
“Further understanding the mechanisms underlying these observations and determining whether they may benefit people with anxiety disorders, for example post-traumatic stress disorder (PTSD) is a current goal of my research”, says Marvar.
High blood pressure is known to be an important risk factor for strokes and heart attacks. There are various drugs on the market, and many patients take them but experience little to no effect afterwards. Therefore many current studies are trying to find a new alternative to these drugs.