The concept of stress and adjustment disorders
Endocrinology / / May 22, 2016
The term "stress" was introduced by Selye in 1936. Literally "stress" can be translated as "stress".
Numerous experimental studies have Selye highlight the complex non-specific changes that occur in the body in response to various specific pathogenic effects (toxicity, infection, burns, physical and mental trauma) and excessive force on the physiological effects (cooling, physical exertion).Factors leading to the development of the non-specific response, they called stressors.Stress, in Selye representations, can be regarded as an integral part of the disease, emerging from specific changes (eg, pneumonia when exposed to pneumococcus) and non-specific reactions - stress.Selye points out that stress - a condition that occurs in the body as a result of attempts to restore balance.From this perspective, the concept of "stress" to a certain extent close to the views of Pavlov the physiological measure against the disease to learning about AD Speransky nonspecific reactions of the organism.
changes that occur in the body during times of stress, Selye described the general adaptation syndrome.The experiment has certain morphological changes characteristic of stress: an increase in adrenal cortex, severe involution thymicolymphatic device, the appearance of stomach bleeding ulcers and duodenal ulcers.
These changes correspond to the shifts that occur in the body at high stimulation of the adrenal adrenocorticotropic hormone, and are associated with excessive amounts of glucocorticoid action.Meaning dientsefalo-pituitary-adrenal system in the implementation of reactions stress has been shown by numerous experiments in violation of the pituitary due to the hypothalamus, the pituitary or adrenal gland removal.
stress reaction, according to Selye theory, determined by the interaction of anti-inflammatory hormones (glucocorticoid) and pro-inflammatory hormones.The latter, in addition mineralocorticoids, Selye relates pituitary somatotropic hormone in experimental conditions which promotes an inflammatory response.It is suggested that the pituitary hormone somatotropin or sensitizes tissues to the action of mineralocorticoid or mineralocorticoid stimulates the adrenal cortex.These hormones, which influence on the course of the inflammatory response, called adaptive hormones.
general adaptation syndrome in its development goes through a series of stages:
1) alarm reaction, consists of two phases:
a) shock, characterized by hypothermia, hypotension, central nervous system depression, a decrease in muscle tone, haemoconcentration.When excessively strong stimuli may come death of the organism in this phase;
b) protivoshok characterized by an increase in the functional state of the adrenal cortex and physiological changes in the direction opposite to the shock - increased blood pressure, muscle tone, etc .;.
2) phase of resistance, which is peculiar to the prevalence of anabolic processes, increased resistance to hazard;
3) with continued exposure or hazard when it comes to excessive intensity of the depletion phase, which is peculiar to the development of degenerative processes and patterns reminiscent of the shock phase and ends with the death of the organism.
In connection with the presentation of the general adaptation syndrome Selye was developed doctrine of adaptation diseases.To those Selye considers those diseases, the development of which can be attributed not only to a specific action of the damaging agent as a disequilibrium between the adaptive hormones.
disequilibrium between adaptive hormones, on presentation of Selye, may be due to various reasons:
1) the influence of conditioning factors - genetic, dietary, influence other stressors, etc .;.
2) the absolute predominance of certain hormones in the adaptation due to excessive or insufficient release of pro-inflammatory or anti-inflammatory hormones;
3) metabolic disorders of hormone in the periphery;
4) changes in tissue sensitivity to the action of hormones.According
Selye, the predominance of pro-inflammatory hormone leads to the development of hypertension, nephrosclerosis, inflammatory reactions - those disease states which are specific experimental conditions can be reproduced by introducing excessive amounts deoxycorticosterone.The prevalence of anti-inflammatory hormones leads to a generalization of infection, development of necrosis in connection with a reduction in the body's defenses.However, even a short-term imbalance can create conditions for the development of adaptation diseases.
Along with the doctrine of the general adaptation syndrome, Selye introduced the concept of local adaptation syndrome, showed experimentally that the focal inflammatory response goes through the same phases as the overall reaction.
against the idea that the cause of a number of diseases is the imbalance between pro-inflammatory and anti-inflammatory hormones, put forward a number of serious objections.Firstly, a number of disease models obtained in the experiment under the influence of pro-inflammatory hormone, can be created under conditions that are very far from those that can occur in human physiology and pathology.Thus, in order to obtain at nephrosclerosis experimental animal must produce unilateral nephrectomy, the animal subjected to exposure to cold, and the sodium load introduce very large doses deoxycorticosterone.There is no evidence that similar effects can be caused by a stressor in vivo.
- Physiology of the adrenal cortex
- chromophobe pituitary adenoma
- Regulation adrenocortical function
- blood supply and innervation of the adrenal
- Diseases pineal gland
- Biological effects of mineralocorticoid
- Biological effects cortex hormonesadrenal glands.The biological effect of glucocorticoid
- Morforfologiya adrenal
- Additional adrenal
- biosynthesis and metabolism cortex hormones adrenal
- Biological effects of C19-steroids
In some diseases, the treatment of which the glucocorticoidhave high activity, established by reducing the 17-gidroksikortikosteroidov in the blood, which would be expected based on the idea of the role of imbalances between glucocorticoid and mineralocorticoid in the pathogenesis of these diseases.However, recently obtained data on the increase in the number of blood transcortin in patients with rheumatoid arthritis.It is possible that in these diseases cortisol is in a stronger bond with proteins than in healthy individuals.Therefore the biologically effective concentration of cortisol can be smaller than that determined by chemical methods.
Thus, Selye and his followers received a number of important facts that reveal the role of one of the regulatory systems of the body in a non-specific adaptive responses.
In assessing Selye theory must take into account its limited value.Exaggerating the role of the pituitary - adrenal cortex inevitably leads to serious methodological errors.In addition, essential data, in some cases requiring the revaluation results of experimental studies that formed the basis of the theory of adaptation diseases, obtained in the development of ideas about the permissive (supporting) glucocorticoid action.
03 May, 2016
03 May, 2016
03 May, 2016