РATHOLOGY OF REACTIVITY

Reactivity is ability of the organism to alter functional activity of the systems and organs for the adaptation of organism to new conditions of the environment for the survival. The concept “reactivity” is connected with the  concept “resistance”.

REACTIVITY is regulated by three physiological levels:1)By Nervous system2)by the endocrine system3)by the local,tissue-specific mechanisms

Systems determining reactivity:1)Nervous system 2)Endocrine system 3)immune system4)monocyte-Macrophage system (reticulo endothelial system)

Resistance is a state of stability of an organism to the influence of pathogenic factors. CLASSIFICATION OF THE RESISTANCE: 1)active2)passive 3)primary 4)Secondary5)specific and unspecific.

Active resistance is a result of the organism adaptation to the long time pathological factor influences. Passive resistance is a result of anatomical and physiological peculiarities of each organism.

Primary (congenital) resistance is a result of the inherited peculiarities of an organism and it manifest itself after birth of the person. Secondary (acquired) resistance is a result of organism functional reactions changes, which occur during the whole life.

Unspecific resistance is the opposition to the influence of many pathological agents.

Specific resistance is the opposition to the defined agent influence, for example, microorganisms; its result is activation of the immune system.

TYPES OF RESISTANCE

RESISTANCE

SPECIFIC NON-SPECIFIC

 (Acquired Immunity) (Innate Immunity)

Third line of defense extrinsic barrier

Skin barrier

Moucus barrier include:

Respiratory tract,GIT,UGT RESISTANCE CONSIST OF :1)FIRST LINE DEFENCE: extrinsic barrier

2) SECOND LINE DEFENCE: phagocytosis,inflamations(intrinsic barrier)

3)THIRD LINE DEFENCE: SPECIFIC IMMUUNE responses

Types of reactivity1)Biological reactivity or typical reactivity:

is a result of the morphological and physiological peculiarities of all individuals, which are of the same biological species. For example: some species of birds, fishes, and animal change the vital activity according to the changes of the seasons.

2)Individual reactivity: is the reactivity of every individual. Individual reactivity is determined by age, sex, heredity, constitution, and functional conditions of organism’s regulatory systems, external environmental influences. For example: some diseases arise only in infant organism (measles, roseola, small pox, rachitis, scarlet-fever) but not in adult’s one.

Individual reactivity of an organism is realized by specific and unspecific mechanisms. The specific mechanisms are formed by immune system. specific physiological mechanisms: of the individual reactivity are the immune reactions, which form the specific resistance to some antigens (bacteries, viruses, fungus, tumours cells). pathological specific mechanisms of the individual reactivity can cause development of the immunodeficiency or immunodepressive conditions of an organism or the allergic reactions and diseases.

The unspecific mechanisms of the reactivity are physiological and pathological. Physiological unspecific reactivity is the vital reactions complex of the healthy organism in normal life conditions. Pathological unspecific reactivity is the complex of an organism’s reactions in abnormal life conditions as a result of the decrease of the adaptive potential of an organism (for example: shock, collapse, narcosis). NECROSIS

CLASSIFICATION of THE “REACTIVITY”Biological determined by the morphological and

physiological peculiarities of all individuals, which are originate from some species

Individual reactivity

sexage

constitution

SPECIFIC

physiological pathological

UNSPECIFIC

physiological pathological

heredity regulatorysystems

environment

 EG:-SHOCK-COLLAPSE-NECROSIS

- immunodepressive conditions

- allergy

In normal conditions In normal conditions during diseaseduring disease

Individual reactivitySome diseases arise only in infant organism (measles, roseola, small pox, rachitis, scarlet-fever). Children are less adapted to sharp changes of air temperature, infant organism is more resistant to the hypoxia, than adults.

MEASLES

SMALL POX

RACHITIS SCARLET FEVER

Mechanisms of the unspecific reactivity are realized by means of

nervous system reactions (central nervous system, autonomic nervous system),

endocrine system reactions; barrier systems; cell’s reactions; humoral reactions.

barrier systemsThe barrier systems preserve an organism against the pathological factors of the external environment. There are external and internal barriers.

The external barriers:The external barriers are skin, mucous membranes, liver, spleen, lymphatic nodes and other organs, which have the cells of the system of mononuclear phagocytes. LIVER

SPLEEN

Internal barriersThere are internal barriers in the organism, which are named

histohematic barriers. Wall of a capillary has the function of a barrier. The wall of a capillary lets in only the nutritious substances and does not let in the toxins, medicines.

Examples of internal barriers: 1.hematoencephalic (blood-brain), 2.hematoophtalmic (blood-eye tissue), 3.hematolabirintic (blood-lymph of a labyrinth), 4.hematoovarial (blood-ovarium tissue), 5.hematotestical (blood-testicular tissue)6.placenta (mother’s blood-foetus blood). Connective tissue, which surrounds the vessels and

penetrates into a tissue, executes the protective function too.

7.hematothyriod (blood-thyriod tissue),

The protective function of barriers is depend on nervous and humoral influences, on a state of the external and internal environment.

The alcohol has specific influence up hematoencephalic barrier. The permeability of this barrier increases during initial stage of alcoholism, so various toxic substances influence up the brain.

Individual reactivity can be changed as a result of influence of the factors of the external environment. Reactivity of an organism depends on ecology. Some changes of an ecological situation can prevent development of disease; others on the contrary provoke development of disease. For example: the small doze of a ultra-violet irradiation increases resistance of an organism to the infectious diseases, promotes synthesis of vitamin D in the organism, and the large doze promotes development of skin burn.

Sharp changes of weather, season of year and climate influence on reactivity and resistance too. Low temperature of air influences on organism variously. The overcooling lowers resistance to the infection, so in such conditions influenza and pneumonia may occur. The short-term contact of a human body with the cold environment, which periodically repeats, increases resistance to the infection. Low temperature (hypothermia) is used in medicine during complex continual operations on the heart and brain.

Clinical classification of reactivity

NORMERGICAL HYPERERGICAL HYPOERGICAL

NORMERGICAL: Common course and symptoms of disease.HYPERERGICAL: Intensive rapid course,with greatly marked symptoms.HYPOERGICAL: Inactive course, poorly marked symptoms.

ERGON MEANS ACT (ACTION)