The reactivity of the organism

Reactivity of organism is a property of an organism to respond to diverse physiological and pathological stimuli environment.
The basis of the reactivity of organism is the reactivity of species, which includes features characteristic of all species, such as seasonal changes of life (summer and winter hibernation, anabiosis, migration and so on) animals. All the animals of the same species have in common, specific for this kind of ability to produce antibodies or play allergic reactions.
However, within the species there are different groups that respond differently to external influence, depending on constitutional differences or types of nervous activity (see the Constitution). People can have a value and nature of professional activity. So, for example, electricians easier to tolerate electric shock, than people without the case with electricity. Such groups, combined with any of the above symptoms, have a shared group reactivity of organism.
Finally, even some representatives of one group differ from each other individual characteristics of the structure or function of the body. Accordingly, and manifestations of their reactivity, which is the basis of individual reactivity. Individual reactivity of organism is determined also by age. The newborn reactivity is more common diffuse, generalized reactions, such as the occurrence of convulsions reactions in a variety of infections (intestinal, flu, diphtheria, and so on). Infectious diseases in children often flow with symptoms of intoxication, often without specific localization. With age, the reactivity of the organism decreases, and the old men many diseases run with little symptomatic, however, is often more difficult than for younger people, which is associated with a decrease in the resistance of the old body.
An important role in the reactivity of the organism played by factors such as cooling, fatigue, low power, hypovitaminosis, which reduces the reactivity.
At various painful conditions reactivity of the organism can change dramatically and beyond, typical of that same body in a healthy condition. In these cases, there is a pathological reactivity, which is characterized by the fact that adaptive - compensatory capabilities of the body with normal reactivity decrease and there are specific response to the effects of pathogenic agents, which largely determine the symptoms of the disease. Thus, when a pathological reactivity of the organism can sluggish flow of inflammation, without raising the temperature and sharp inflammatory changes; can be broken recovery processes (wound healing, bone consolidation), weakened immune reaction. In clinical practice it is necessary to approach to the prevention and treatment of diseases taking into account reactivity of organism.

The reactivity of the organism - the property of an organism to respond to environmental factors change in your life, that provides some degree of adaptation of organisms to the environment.
The range of current physiological fluctuations R. O. determine changes in the level of activity of the physiological systems under the influence of ordinary (adequate) stimuli.
In the evolutionary aspect R. O. was improved in accordance with the development of systems that perceive irritations of the external environment and correlating physiological functions in the body. Therefore reactive properties are usually more pronounced among the higher animals and less in organisms with a primitive nervous organization. In physiological terms R. O. partially reflected concepts irritability and anxiety.
Reactivity of the organism is determined by the genotype of an organism and is a kind of species sign able, however, to change significantly. It depends on the potential of the body to change the level of activity of the physiological systems in accordance with the requirements of the environment, i.e. on its physiological Constitution, in particular to the type of the nervous system.
In clinical practice the term "reactivity" is used to describe the peculiarities of the development and course of the disease among separate individuals. This refers to the distinctive ability of the body to respond to the effects of pathogenic factors by deploying specific and nonspecific protective and compensatory reactions, opposing harm.
There are special forms of response of the body that are related to the impact of foreign proteins, microorganisms and their toxins. In such cases they say about the immunological reactivity of the organism (see Immunity) and allergic R. O. (see Allergy).
The following types of reactivity of the organism. Biological, or species, reactivity includes the most characteristic features of physiological and pathological reactivity, the nature of this type of animal. This is manifested, for example, the seasonal changes of life (suspended animation, summer and winter hibernation, migration of fish and birds associated with the time of year, reproduction), in various species ability to production of specific antibodies and reproduction of allergic reactions in different animals. Group reactivity is formed on the basis of species. In humans and higher animals group features reactivity due to constitutional differences, in particular different types of nervous system (see the Higher nervous activity).
Individual reactivity depends on the characteristic features of the individual - his Constitution, sex, age, living conditions. Determine the nature of individual reactivity of organism, leading physiological features of this body - the type of the nervous system, particularly endocrine glands and other functional systems.
The reactivity of the organism of the child differs significantly from that of an adult. In the first months of life a tendency to diffuse, generalized reactions. Infections are expressed with the General reaction - intoxication-cramps - with weakly expressed in the local manifestations of the process. Such nature R. O. due to low activity of the protective mechanisms - inferiority of barrier functions (see), phagocytic activity of leucocytes (see Phagocytosis) and reticuloendothelial system, decreased ability to produce specific antibodies and other
With age, with the development of the nervous system and the establishment of reciprocal relationships between the glands of internal secretion, characteristic for the adult, R. O. child becomes more perfect.
Under the impact on the body "emergency" malicious factors reactivity him in respect of these things can change so that far exceeds the range of its physiological fluctuations characteristic of this species. Then there is a pathological reactivity, which is characterized by the appearance of painful disorders and General decrease of adaptive-compensatory abilities of the body. Thus, in some forms of toxicosis of pregnancy have been violations of the reactivity of the organism allergic type, which carry the names of allergies. It is often arise response of the body in the form of dyspnea, fever, increased sweating, etc. that are non-specific symptoms disease. Pathological reactivity plays an important role in the pathogenesis of many diseases, causing a specific response to the effects of pathogenic agents that form in each case, the characteristic picture of diseases (rheumatism, hypertension, bronchial asthma and other). Cm. also Adaptation syndrome, the body's Resistance.