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Administration of heparin led to the block of the alarm reaction of the general adaptation syndrome in rats. The results obtained could be explained by the binding of adrenal cortex hormones by heparin or by an increase in the resistance of tissues to stressors as a result of reversible block of the enzymes of the respiratory energic cycle in the cells.
In order to study the effects of a magnetostatic field on the organism, continuous exposure was applied and the resulting effects were observed for a period of 20 days. The Ss were four rats which were continually exposed, one by one, to a vertical field of 2800 oersted for uninterrupted periods of time. In a first series of experiments, the variation of the sleeping period for each of the four SS was observed. An evolution quite characteristic of the different phases of the general adaptation syndrome was noted: reaction, counterreaction, and resistance. The same phenomenon was observed in the response under delayed reinforcement of low rate (DRL) at 5 and 10 seconds. In each case, a slowdown of the weight growth was noted. One can thus consider the magnetostatic field as an agent responsible for a nonspecific general effect similar to other stressing agents. These behavioral observations suggest a verification of these effects on the endocrine system and illustrate the necessity of long exposures for the study of specific and nonspecific effects of the exposure to the magnetostatic field.
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Studies were conducted with the view to elucidating the correlations between increased glucocorticosteroid levels in the blood and the defense potential of calf organism against infectious diseases. The test animals were exposed to several substances (ACTH, cortisol, colibacteria, coliendotoxin), and even one to two days of increased 11-OHKS values were followed by marked decline in phagocytosis activity of leucocytes. In addition, RHS function was considerably reduced, after ten to thirteen days of application had elapsed, since at that point the disappearance of intravenously applied bacteria from circulating blood of test animals took place at rates which were much lower than those recorded from untreated calves. Differentiated length of stress or action (four to thirteen days) was followed by conspicuous changes in the lymphatic tissue of calf organism, with severe involution of thymus and follicular atrophy of intestine-associated lymphatic tissue having been the major findings. The results seem to suggest that rise in adrenocortical hormone level under stress may reduce potential organic defense to infection.
The stage of rat long-term adaptation to chronic emotional-pain stress is characterized by an increase of superoxide dismutase brain activity and superoxide-scavenging blood serum activity, accumulation of fluorescent products of free-radical oxidation, reduction of phospholipids and cholesterin contents in the brain lipid extracts. In the process of prolonged adaptation to the continuing chronic emotional-pain stress three periods are singled out, each of which with a definite correlation of characteristics of vegetative functions, behaviour, intensity of free-radical oxidation and antiradical defence.
The action of experimental and natural stressors on the humoral immune response of calf was studied. Particular attention was given to the H-antigen of S.dublin and equine erythrocytes,the degradation rate of passively acquired humoral antibody, as well as the quantity and topographic distribution of certain groups of germs in the gastrointestinal tract. The following results were obtained:1. Antibody formation was impededby repeated or lasting stressor effect (ACTH injections). 2. The immunological reactions of the calves involved to antigen injection immediately after transport into the rearing unit were stronger than those to antigen application three days from transfer. Immunisation of animals transferred to rearing or fattening units, therefore, should be applied immediately after arrival in the new accomodation, but no interval of three or four days should be allowed. 3. Antibody formation was no longer impaired in calves immunised two weeks from transfer, as compared to those immunised immediately after arrival in the rearing unit. This seemed to suggest that by that time adaptation of the animals to their new environment had been almost complete. 4. Lasting stress (slow drip infusion of ACTH, cortisol, colibacteria or coli-endotoxin) led to no detectable by paper electrophoresis. 5. Calves that had been given three weekly dosesof 1 IU ACTH per kilogram of live weight through four weeks,did not differ,withthe authors'method,from the controls regarding the decomposition rate of passively acquired humoral antibody. 6. ACTH slow drip infusions of calves over several days caused higher concentrations of colibacteria throughout the intestinal tract, including those proximal sections of the small intestine in which little or no colibacteria should occur under physiological conditions in calves of that age.
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Two major sources of theoretical development for biofeedback as an intervention paradigm are considered. An integration of cognitive learning theory approaches to the potential regulation of autonomic processes in an information-processing framework and the phenomenological information-processing approach of Kelly's personal construct theory suggest a new methodological paradigm for biofeedback as a tool of psychotherapeutic intervention, especially for the discipline of behavioral medicine. Biofeedback is reconstructed as a sequence of allocating attention to automatic cognitive processes until cognitive control has been mastered. This sequence is also seen as a circumspection-preemption-control cycle that Kelly (1955) suggested was essential to all problem solving. In light of Kelly's fundamental assumptions regarding the nature of constructs, it is suggested that controlled processing approaches to biofeedback require the biofeedback trainee to investigate both ends of psychophysiological dichotomies instead of demonstrative constructs of traditional biofeedback methodology. Other psychotherapeutic techniques are reviewed to validate this new theoretical approach. Finally, treatment within this paradigm is discussed as a recircumspection of relevant constructs that were routinized during the alarm reaction phase of Selye's general adaptation syndrome.
The stressing action of a medium-intensity, magnetostatic field was studied for several levels of intensity. Our purpose was to verify a stressing action by display of the general adaptation syndrome pattern on the growth rate of mice and to establish the relation between effect and field intensity on the same variable. Eight groups of mice showed a linear relation. Moreover, stressing action was noticed at lower intensities than previously suggested.
Most afferent inputs are sensory stimulants, and physical activity is probably one of the most significant of all sensory stimulations. Gravity is a constant stimulus. These demands are also known as stress, and the stressor effect as the general adaptation syndrome (Selye). In this study, these demands are called sensory afferent stimuli, which are necessary triggers to start the hypothalamus-pituitary-adrenal mechanism and thus maintain the general mechanical, autonomic and metabolic functions of the body in the state of homeostasis. If the sensory stimulus is removed, there is no stressor effect and the cycle of response is eliminated. This results in a decreased hypothalamus-pituitary response and a decreased production of ACTH and corticoids. A decrease in the sensory input creates changes in the central nervous system and in the musculoskeletal system which are compatible with lack of the hypothalamus-pituitary responses. When a person becomes ill, physical inactivity as well as sensory and perceptual deprivation are at a maximum, and the absence of these stimuli interrupts the cycle of homeostasis. Physical activity is one of the most important stressors (sensory input) or triggering mechanisms for the cycle of homeostasis (hypothalamus-pituitary-adrenal cycle). Therefore, it is imperative to provide the patient with physical activities which ensure motion and take into account the effect of gravity. This is best accomplished by a program of physical, occupational and recreational therapy.
The authors conducted two series of experiments on 144 mice of BAL/c and C57B1 line. It was established that in autotransplantation submicroscopical changes developing in somatotropinocytes are typical of stressor situation and reflect various phases of general adaptation syndrome. An increase in the number of cells in the phase of active proteinic synthesis and degranulation is observed in allotransplantation in inductive phase of immunogenesis. Before rejection the number of cells in the phase of active proteinic synthesis is decreased, and in degranulation phase--is increased.
The object of this work was to establish whether induced stress leads to morphological changes in the sublingual and submaxillary glands of rats. General adaptation syndrome (S.G.A.) was induced in 25 young adult male Wistar rats through cold and immobilization. The animals were killed 48 hrs. and 10 days after stressor (E.A.) application. To verify stress condition, the adrenales were weighed and plasmatic corticosterone were carried out. The sublingual and submaxillary glands were dissected, fixed in buffered formol and stained with H.E. The results histology indicate that the submaxillary is more sensitive to cold than the sublingual, while the reverse holds true form immobilization.
The literary data and own results concerning the stages of free radical lipid oxidation inhibition during the adaptation of animals to stress are reviewed. Using the chronic stress models such as immobilization, experimental neurosis, it has been shown, that in general adaptation syndrome the stage of permanent adaptation to stress corresponds to a permanent inhibition of free radical processes in animal tissues. This stage is accompanied by the activation of superoxide radical scavenging and corresponding changes of lipid composition. similar results are obtained on the model of the development of permanent compensation processes after brain injury. Studying the acute stress it has been found, that during first minutes the inhibition of lipid peroxidation which precedes its further activation takes place. This stage corresponds to the realization of urgent adaptation phase to stress. The role of inhibition of free radical processes in mechanisms of urgent and permanent adaptation to stress is under discussion.
An overview of the main problems and misconceptions in the clinical application and theoretic evaluation of the stress concept reveals that the same 10 problems appear to cause the greatest difficulties in its application, irrespective of the specialty in which it is used: (1) the correct definition of stress, stressors and the general adaptation syndrome; (2) the concept of nonspecificity in biology and medicine; (3) the conditioning of stress responses by diverse endogenous (mainly genetically determined) and exogenous (environmental) factors; (4) the relation between the genral and the local adaptation syndromes; (5) the difference between direct and indirect pathogens; (6) the definition of the morbid lesions in whose pathogenesis stress plays a particularly prominent role--the so-called diseases of adaptation; (7) the role of genetics versus that of factors under voluntary self-control in mastering biologic stress; (8) the mode of action of syntoxic and catatoxic hormones, drugs and behavioural attitudes; (9) the so-called first mediator of the stress response, which carries the message that a state of stress exists from the directly affected area to the neurohormonal regulatory centres; and (10) the prophylaxis and treatment of stress-induced damage by pharmacologic and behavioural techniques.
The appropriate literature has been reviewed for the purpose of defining the phenomenon of stress in lactating dairy cattle, establishing a baseline concept of lactation stress and emphasizing the most significant aspects of the natural mammary defence mechanisms. Data on the general adaptation syndrome (GAS) make it clear that stress is essentially the rate of wear and tear of the biological system affected by a stressor either eliciting stress of the organism as a whole or partly so. Owing to the variety of stressors which may affect the dairy cow at physiological and pathological levels, a definition of stress in the broad sense is indicated. This is essential from the point of view of the anti-homeostatic effects (metabolic and immunological) of lactation stress, aggravated by anti-homeostatic effects elicited by superimposed other types of stress (e.g. heat stress). The lactating cow, as a ruminant in a state of sustained stress, requires a special profile of hormonal mediators. In high yielding cows, for example, acute and sustained heat stress promotes increased activities of prolactin, progesterone and catecholamines. Compared with the mainly glycogenic/glycogenolytic metabolism of non-ruminant mammals, the lipogenic/lipolytic and glycogenic/glycogenolytic metabolism of the dairy cow depends on hormonal mediators which differ from those of the former not so much in their nature but in their magnitude and ratios. Stressors induce the development of GAS reactions in the dairy cow. These enable the cow to create and maintain homeostasis of its integrated 3 main physio-pathological systems and thus to endure the stressor(s). The cow's compensating adjustments to a stressor are therefore the effects of stress. This means that natural lactation is the effect of the lactation stress induced by the cow's progeny (i.e. the natural lactation stressor). Artificial lactation stressors (e.g. removal of milk by hand and machine) may affect the lactation stress in magnitude but not necessarily in nature. Likewise, a range of behavioural, physiological, lactational and lacteal changes related to other stressors are the effects of different types of stress. Lactation stress, like other types of stress, shows 3 stages of development, i.e., an overcompensating alarm phase (= lactogenesis), resistance phase (= galactopoiesis) and exhaustion phase (= regression). They facilitate adjustments of the cow's homeostasis from the level of involutional homeostasis (= no lactational activity) to that of lactational homeostasis. Like other tissues in a state of stress, the lactating mammary epithelium requires a greatly increased supply of glucose.(ABSTRACT TRUNCATED AT 400 WORDS)
Intravenous infusion of glucose in high dosage was given to 42 tumor patients, attaining a hyperglycemia of about 40 mg/100 ml over a period of 24 hours. This hyperglycemia is a part of the so-called "cancer-multistep-therapie". During the period of glucose-infusion a water-turnover of about 6,000 ml can be registered which is connected with a requirement of glucose of about 2,000 g. Only 1/3 of this amount is loosing by renal excretion, but 2/3 are metabolised to correspond with a glucose-uptake of 0,94 g and a glucosuria of 0,32 g per kg bodyweight and hour. Requirement of glucose and glucose uptake are in inverse proportion to the age of the patients and to the duration of hyperglycemia. Further a "glucose-potassium-equivalent" existed: about 10 mval potassium per 100 g infused glucose, whereas the netto uptake of potassium is 0,049 mval per g of metabolised glucose. Acid-base-equilibrium and red blood-picture did not show any relevant variations while typical deviations of some other parameters (cardiac-frequency, body-temperature), white blood-picture) are can be associated with the so-called "general adaptation syndrom". The findings are discussed in view of their general importance for the parenteral application of glucose.