Study of the inhibition of histamine release by inosine pranobex

The effects of Inosine pranobex and its parent compounds inosine and dimethylamino-2-propanol-p-acetamidobenzoic acid (DipPacBa) on the Concanavalin A (ConA)-induced histamine release from human adenoidal mast cells were investigated. Inosine pranobex inhibited the ConA-induced histamine release at concentrations greater than 10(-3) M. Inosine itself (10(-5)-10(-2) M) enhanced the ConA-induced histamine release whereas DipPacBa inhibited the release significantly at concentrations between 10(-6) and 10(-2) M. These results are consistent with the assumption that the effect of Inosine pranobex is due to the DipPacBa moiety.