Intracellular adenosine inhibits IgE-dependent degranulation of human skin mast cells.

Purpose: Adenosine (ADO) can enhance and inhibit mast cell degranulation. Potentiation of degranulation occurs at relatively low concentrations of ADO (10−6–10−5 M) through triggering of A3AR, whereas, inhibition occurs at higher concentrations of ADO reportedly through triggering of A2aAR. However, the discrepancy in the concentration of ADO that inhibits degranulation and that required to trigger ADORs suggests a different mechanism.