Inhibition of histamine release and ionophore-induced calcium flux in rat mast cells by lidocaine and chlorpromazine.

We studied the effects of lidocaine (L) and chlorromazine (C), two compounds known to affect the binding of calcium to cell membranes, on histamine release and calcium uptake by purified mast cells upon challenge with the ionophore A23,187 or with compound 48/80. At low concentrations L and C inhibited the Ca++ flux as well as histamine release while higher concentration caused enhancement in this function. Evidence was obtained that L 10(-4) M may displace Ca++ from the cell membranes.