Stress biology
The invention of the term
In 1936 the zoologist Hans Selye borrowed the term from physics. He wanted to name the »unspecific reaction of the body towards any kind of demand«. In the science of materials, stress means the strain or pressure on material (see strain, material fatigue).
Seyle invented stress for biology
Hans Selye was born on January the 26th, 1907 in Vienna, Austria and died on October the 16th 1982 in Montreal, Quebec. He was a Canadian medic with Hungarian ancestry and Austrian citizenship.
In the 1930ies he developed the basics for the teachings on stress and the general adaptation- syndrome or Selye- syndrome. Therefore he is named the »Father of stress research«. In 1934 he emigrated to Canada. Since his first publication in 1936 about defining and identifying »stress« he has written more than 1700 papers and 39 books on the subject.
»I have given all languages a new word: stress«, Selye said in the abstract of his life's work. At the time of his death in 1982, his scientific assignments counted over 362.000 and quoted in innumerable stories in most languages and all countries. To this day he is still the most quoted author on the subject. Source: Wikipedia
The stress response
A biological process to maintain different states of balance
Stress response is a strictly choreographed biological process. It adapts our organism to the interior and exterior conditions of life. The stress system is basically made up of the CRH (corticotropin-releasing hormone-, cortisol- and catecholamine, adrenaline, noradrenalin) - control cycles. They are situated in the central nervous system and follow close rules when processing stressors and impulses.
These control cycles are closely connected to the enteral nervous and immune systems as well as various organ systems, such as the cardiovascular system and the respiratory system. Experiments have shown that the CHR system projects over a chain of switching circuits into the central nervous system directly to the lower part of the colon. The stomach is also under the systems' immediate influence.
The stress system monitors, controls and co-ordinates all processes in the body. It then sends the relevant signals to the central nervous system for target/performance comparison. Here the system arranges the necessary adjustments or initiates them. If possible, an individually defined target/performance balance is held constantly. This is meant as a kind of safety margin in case of emergency. It ensures that our body never operates at a maximum level.
Athletes recover very quickly
after extreme strain - why?
An Athlete can recover in a matter of seconds, even though collapsing from exhaustion a few moments earlier. If his condition were really serious – which can happen - he would have to be taken to intensive care in order to stabilize the state of shock he is in.
The higher meaning of all these actions is always the perpetuation of the dynamic balance (homoeostasis). Therefore the type of stressor itself is not important. The organism does not differentiate between conscious and unconscious impulses. Neither does it make a difference between stressors from the inside of the body and those from the surrounding environment.
Humans possess different abilities to conquer burdening situations. These abilities depend on their genetic outfit and the experience they have gathered in dealing with those kinds of situations from the day of their birth.
So what is stressful to one individual does not necessarily mean stress for another. Dealing with stress ineffectively can lead to a chronic stress exposure. Let us observe an overactive stress system and, as a part of it, a deregulated immune system. The weakest symptoms of such a chronic stress impact are probably loss of motivation and lack of drive mixed with a general feeling of being unable to cope and loss of control. But a depression or chronic disease can arise, if triggered by an additional stress impulse such as illness, injury, job-related or family burdens combined with lacking phases of regeneration. Often a dysfunction of the gastrointestinal tract is only the beginning of such a development.
Irritable bowel syndrome and other digestion disorders are the results of an insufficient manner of dealing with stress.
Irritable bowel syndrome and indigestion
Experiments on different animal models have clearly shown how sensitive the gastro-intestinal tract is. Different kinds of stressors like exposure to coldness or withdrawal of love and security, lead to a delayed emptying of the bowel and a raised motility of the lower large intestine with combined diarrhea.
Research on the effects of chronic stress to the gastrointestinal tract, is still scarce. But there are already a line of hints that irritable colon and other indigestion problems root here. Most people who suffer from these dysfunctions have been through traumatizing events shortly after birth or at a young age, so that their ability to process stress properly has already been damaged.
Another piece of evidence concerning the consequences chronic stress has on the intestine is the fact that chronic stress leads to a higher permeability of the intestinal mucosa. The reason for this could be the more developed inflammatory component in the intestinal area. This, on the other hand, predisposes to bacterial gastro-enteritis, the consequence of which can often be post-infection irritable bowel syndrome. Because of the hindered stress response, some immune controlling processes are underdeveloped or missing altogether. It counts as a fact that the stress control cycles in the central nervous system control the stomach and the intestine and vice versa.
It is one of the most central control cycles for health and well-being. Sadly enough the deregulation of these complex switching systems is increasing constantly. Not only does the origin of all the named dysfunctions seem to lie here, but also the origin of chronic inflammatory intestinal diseases, if the genetic disposition is given. The increasing rate of chronic inflammatory intestinal diseases speaks for itself here.