[Cytomorphological characteristics of mastocytes following experimental anaphylactic shock]

Certain histological and ultrastructural changes occurring in mastocytes at the time of experimentally induced anaphylactic shock were studied in various guinea-pig organs (skin, tongue, spleen, liver). The known histo-functional states of histaminic secretion from the mastocytes--degranulation, fusion and disruption--were manifested to a varying extent. Entirely preserved mastocytes as well as such with obviously non-recoverable shape and function were observed light-microscopically. Characteristic secretory granule changes, formation of exocytic vacuoles, and ducts as well as evident granule exocytosis were found electron-microscopically. Along with that separated vast mastocytic cytoplasmic parts carrying non-secretory granules were observed. These were the result of direct contacts with activated macrophages. In the spleen, macrophages showed a tendency to phagocytize completely the secreting mastocytes. The conclusion is drawn that cytomorphological mastocytic changes following fatal anaphylactic shock are not of the same type. Most probably, in vivo, besides the IgE-mediated histamine release preserving the cells integrity, cytotoxic and immuno-complex allergic reactions take place, which finally lead to cytolysis or phagocytosis of the secretory mastocytes.