The role of stress in the pathogenesis of human diseases
In the modern world, people often use the word “stress” and make it synonymous with experiences, anxiety, or intense excitement. Nevertheless, the term is much broader and in medical terminology has not only a negative connotation.
Today, the term “stress” means the nonspecific response of the body to extraordinary stimuli (stressors). At the same time, by its biological nature, stress is an adaptive reaction that occurs under the influence of unusual, extraordinary, or extreme effects on the human body, contributing to adaptation of the body to new conditions. However, with a sufficiently strong and prolonged exposure to the stress factor, there may be a breakdown of adaptive (compensatory reactions), which leads to a state of distress.
In most people, stress is associated mainly with emotional tension, while other stimuli can be stressors, e.g. the action of high and low temperatures, injuries, excessive physical activity, infection and intoxication.
The action of the stressor is realized through receptors of the peripheral nervous system. For example, some people pass out when see blood. In this case, a visual analyzer responds to the stressor. Stimulation of the receptor activates the autonomic nervous system (mainly its sympathetic part) and enhances the formation of some biologically active substances (BAS) in brain (hypothalamus and pituitary gland), which cause changes in other systems of the body. In particular, adrenocorticotropic hormone (ACTH) stimulates the secretion of glucocorticoids (cortisol or corticosterone).
Under the influence of sympathetic impulses, catecholamines are released from adrenal glands (including all known adrenaline). Catecholamines are designed to supply the body with energy, improve blood supply to muscles and stimulate the activity of the central nervous system, which contributes to the adaptation of the body.
However, there are situations where environmental requirements cannot be met through the activation of adaptation mechanisms, which after a certain time can lead to a state distress, which can become the basis for the development of the disease.
Interestingly, in the case of emotional stress, the leading moment is most often not the events themselves, but how they are interpreted by a person, i.e. it is about the peculiarities of his personality. The most important factor to overcome emotional stress is psychological protection (for example, in the case of illness — religious faith, denial of the seriousness of the disease).
The defeat of a target organ that “chooses stress” depends on a few factors: genetics, biological predisposition of the organ to damage, environmental conditions including nutrition, infections, physical tension.
At the heart of diseases caused by chronic stress is prolonged and (or) intense stress of the above systems, as well as the imbalance of other hormones (somatotropic, thyroid, insulin and glucagon, etc.). The so-called “adaptation diseases” include diseases of:
- Cardiovascular system (hypertensive disease, coronary heart disease);
- Gastrointestinal tract (peptic ulcer of the stomach and duodenum, nonspecific ulcerative colitis);
- Immune systems caused by generalized immunosuppressive effect (autoimmune diseases, tumors).
- Poryadin G.V. Stress and pathology. – М.: RGMU, 2009, 23 с.
- Berezov T.T., Korovkin B.F. Biological chemistry. – M.: Medicine, 2002.