[Mast cells as regulators of tissue homeostasis and their place in the series of biological regulators].

The most essential features of the mast cell are continuous production (and partially also absorption from the environment), deposition, and secretion of the two groups of biologically active substances of the regulatory type: heparin and other acid clycosaminoglycanes, and also histamine and, probably, other biogenic amines. These substances are antagonists and have an influence on the homeostasis of the microregion (capillary-connective tissue-parenchyma) -- the main area of action of the mast cells. The mast-cell population is characterized, as compared with other cellular populations of the microregion, by a smaller size, greater morphological and functional diversity, functional duality (capability of producing both a positive and negative effect), and therefore possesses a number of essential properties the biological regulator should meet. The system of mast cells differs from the regulators of a higher order (the nervous and endocrine system) by a smaller radius of action and a greater simplicity of the structure, the latter manifests itself in equality of all its components. The conclusion is drawn that mast cells may be considered as the regulators of tissue homeostasis and a last link in the general reaction of adaptation at the cellular level.