The sequence of biochemical processes

  • The role of biologically active substances
  • The autonomic nervous system
  • Currently, when a well-established phenomenon of anaphylaxis, it is known that severe clinical manifestations in anaphylactic shock caused by a number of biologically active substances that are exempted by reacting antigen - antibody. It was shown that separately antigen and antibody cause no pathological changes, but adding specific antigen to serum containing antibodies formed very toxic complex antigen - antibody. What caused the toxicity of this complex? Some researchers suggest that the complex antigen - antibody formed by the accumulation of molecules in liquid environments of an organism, after adsorption of complement becomes toxic and causes characteristic of allergic lesions. Other researchers (for example, Henry Dale) believe that the complex antigen - antibody, fixed on the cells, causes disturbance of cell metabolism, which are the cause tissue lesions.
    This hypothesis can be schematically presented as follows:

     Antigen: Antibodies, fixed on sensitised cells 
     p 
     Activation of cellular factors (enzymes) 
     p 
     Inactive intracellular mediators 
     p 
     The release of biologically active substances (neurotransmitters) from cells 
     p 
     Local and General tissue damage 
    

    There are a number of hypotheses on this issue, but the scheme in General reflects the current state of knowledge about the mechanism of the damaging action of complex antigen - antibody.
    Position about fixing cells antibodies is important in the pathogenesis of allergic reactions, otherwise it is impossible to explain a number of pathological processes characteristic of these reactions. Part of cellular enzymes in the pathogenesis of allergic reactions confirmed by the following facts: a) anaphylactic reaction takes place only in the presence of oxygen; b) tissue is heated to a temperature of 44° causes inhibition of allergic reactions; in the last flows in the presence of some cations, such as CA++.
    Action antigen on sensitised tissue causes a number of morphological cell disorders, sometimes very significant. A vivid example of morphological disorders cells exposed to complex antigen - antibody is fat cells. Investigations by means of a contrast microscope shows that the fat cells are unevenly distributed in various tissues. Rich in fat cells serous membranes, capsule liver; thickly are fat cells around vessels and bronchi. Under the influence of a specific antigen is an "explosion" fat cells, while intracellular granules outside of it. Fat cells attract the attention of researchers, as rich histamine, heparin, 5-oxitriptofana - biologically active substances, which plays a major role in causing tissue damage in allergic reactions. Studies of the role of these biologically active substances in the pathogenesis of allergic reactions is very important.