ROLE OF MAST-CELLS, BASOPHILS AND THEIR MEDIATORS IN ADVERSE REACTIONS TO GENERAL-ANESTHETICS AND RADIOCONTRAST MEDIA

General anesthetics and radiocontrast media (RCM) can cause anaphylact ic or anaphylactoid reactions. These are usually underdiagnosed and un derreported, but their incidence is apparently rising. Their pathogene sis is complex and not completely understood, but the release of vasoa ctive mediators from basophils and mast cells plays a central role. Th e recent development of in vitro techniques to study the release of pr eformed (histamine and tryptase) and de novo synthesized mediators (PG D(2), LTC(4), and PAF) from purified basophils and mast cells has made it possible to quantify the mediator-releasing activity of anesthetic s such as muscle relaxants, general anesthetics, opioids, and benzodia zepines and RCM on human basophils and mast cells isolated from lung, skin and heart tissues, The majority of general anesthetics and RCM te sted induced only the release of preformed mediators (histamine and tr yptase), not of the de novo synthesized eicosanoids. There was wide va riability in the response of basophils and mast cells from different d onors to the same drug or RCM, presumably due to the releasability par ameter, Hyperosmolality is probably not the only factor responsible fo r basophil and mast cell activation by RCM. The in vitro release of hi stamine induced by anesthetic drugs and RCM was correlated with the re lease of tryptase, Given the longer half-life of tryptase than histami ne in plasma, measurements of plasma tryptase may become a useful diag nostic tool for identifying adverse reactions to anesthetics and RCM.