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Stress like relativity, is a scientific concept
which has suffered from the mixed blessing of being too well known and
too little,” says Dr. Hans Selye. It is an old observation that stress or
tension by itself can produce different diseases in man. People are known
to have gone made in a situation of extreme mental stress. They are also
known to have died suddenly, obviously because of a heart attack. Yet it
is not very long ago that the scientific proof of how it happens became
known.
Stress Syndrome: In 1036, Dr. Hans
Selye while doing research at the Mc Gill University in Canada, made
extracts of the ovaries of the female rats in order to study the effect
of its hormones. He injected a new extract into female rates whose
ovaries had already been removed. The results were as unexpected as they
were baffling. He found the adrenal glands greatly swollen, the lymph
nodes degenerated, and ulcers in the stomach and intestines. The whole
body had in a way become a wreck.
He thought that he had inadvertently introduced
a toxic material in the extracts that he had injected. Then he injected,
instead of the extract, a solution of a known toxic substance,
formaldehyde. It produced a similar effect in the rats.
In spite of the said results, he was not
entirely convinved that the effects were due to the injection of a toxic
material. Could such effects be produced by other means? He kept his rats
in the extreme cold on the roof top of his laboratory. Some of these rats
lived for quite some time, but ultimately succumbed to such a treatment,.
Another batch of rats was put in motor-driven revolving cages and they
ultimately died of exhaustion. Both the above groups of rats showed
effect in their internal organs similar to those observed after the
injection of the new ovarian extract or the injection of formaldehyde.
A picture emerged: an injection of an ovarian
extract or of formaldehyde, or exhaustion due to prolonged cold or to
prolonged extension- the latter two acting only as non-specific
stress-killed rats producing a picture of swollen adrenals, degenerated
lymphatic system and stomach ulcers.
It become obvious to him that the effects
produced in different organs were the result of the stress, which the
animals experienced in all these different situations. He still had to
confirm his hypothesis.
By that time it was known that the pituitary
controlled the action of different other hormonal glands, including those
of the ovaries and the adrenals. Hans Selye thought that tampering with
the pituitary might provide to clue to the action of the ovarian extract
and thus explain the mode of action of stress upon the body.
He removed the pituitary glands in the rats and
then repeated the above experiments. Thus time no damage occurred. Next,
he removed the adrenals but left the pituitary and then repeated the
experiments. The body was damaged, though less than with the initial
experiments. From these experiments, Dr. Selye concluded that stress
produced its effect upon the body through the pituitary and the adrenals.
Such an effect occurred in those rats who
survived long in these experiments. Those who died much sooner did not
develop such lesions. Further experiments that when an animal was put
under stress, its body responds immediately to it making certain changes
in its activities. When the stress was continued, these changes become a
regular feature. And if the animal remained under stress for a prolonged
time, these changes exhausted the body and ultimately caused its death.
To the initial response, Dr. Selye gave the name
Alarm Reaction as it ‘represented the bodily expression of a generalized
call to arms of the defensive forces in the organism’. The next phase he
called the Stage of Resistance of Exhaustion as in this the animal
adapted itself to the stress producing environments. The last phase, he
called the Stage of Exhaustion as in this the animal showed the signs of
premature wear and tear.
The entire syndrome, including its pattern of
development in time, was called the General Adaptation Syndrome.Alarm
reaction is the body’s response when it is suddenly exposed to stimuli to
which it is not adapted.
This reaction has two phases:
Shock Phase: It is the initial and
immediate reaction to the noxious stimulus. Various signs of injury such
as rapid pulse rate, detected temperature, lower blood pressure and loss
of muscle tone are typical symptoms.
Counter phase: This is a rebound reaction
marked by the mobilization of defensive forces of the body, during which
the adrenal cortex in enlarged.
The Stage of Resistance is known is when the
person’s full adaptation to the stress and the consequent improvement of
disappearance of the symptoms occur. At this stage, however, there is a
consequent decrease in resistance to fresh noxious stimuli and stress.
The Stage of Exhaustion sets in if the stress is
sufficiently severe and prolonged because body’s adaptability to stress
is limited and exhaustion inexorably follows. Various symptoms of
diseases appear and if stress is unabated, death follows. Dr. Selye’s
researches showed that stress or tension, particularly is it is
prolonged, is very harmful to the body.
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