Sudden fear, cause changes in the immune system at the molecular level

It is well known negative effects of chronic stress, which under the influence of reduced immunity, and we become weak and susceptible to various diseases. Much less well known is the effect of sudden fear caused by the thrill, for example, when jumping with a parachute. Can a sudden fear lead to the same changes as the stress?


A team of researchers from several institutions (the University of California at San Diego, the University of Stony Brook, and others) have studied the question of the impact of sudden stress, analyzing the blood test before and after the jump with a parachute.

The study involved 39 people (24 men and 15 women), who independently of each other, at different times in a parachute jumping school in New York for the first time in my life in tandem with an instructor. All participants were healthy adults people with no mental health problems and cardiovascular diseases. Blood sampling was carried out at all at 9:15 am during the week before and after the jump. On the day of the jump all the participants woke up at 6:30 am and arrived at the point of collection of blood, where at 9:15 am they took the tests. Further, every 15 minutes, starting from 9:15, they were taken analyzes of saliva. The jump in the readings took place at 10:30 am, when the plane reached a height of 3.5 km. Paratroopers landed after 5 minutes, and the instructor immediately took their tests, and at 11:30 - the hospital.

Researchers have identified the genes affected, and the effect of acute stress way to purchase and innate immunity. Short-term stress provoked a bundle of different immune responses, some of which are useful and some are not. Thus, there was an increase in T-lymphocytes - immune cells that are responsible for recognizing cells of an organism, mutated by infection or cancer, and skin regenerating capacity decreased. However, most of the indicators returned to the natural level one hour after the jump. The researchers caution that if the tension regularly repeated, the fear has not add health. Prolonged stress, the number of leukocytes in the blood is greatly reduced, and recovery to normal can take several months.

Interestingly, at the cellular level changes at stress in women subjects and men differ, which may further help to explain the gender differences observed in the development of cardiovascular and autoimmune diseases that are directly related to stress or post-traumatic stress disorder, which is two times more common among women.