Bradykinin, kallidin (Lys-bradykinin) and [Thi 5,8, D-Phe7]-bradykinin, a functional B2 antagonist, induce histamine release from rat peritoneal mast cells. The histamine release is dependent upon added calcium when mast cells are placed in calcium-free medium 30 min before being triggered with the kinins. Histamine release was dose-dependently inhibited by pertussis toxin (1-100 ng/ml) and by benzalkonium chloride (0.1-3 micrograms/ml). The efficiency of ionophore A23187 on histamine release was affected neither by pertussis toxin nor by benzalkonium chloride. The parallel response of rat peritoneal mast cells to kinins and to substance P suggest that these peptides have the same mechanisms of action i.e. activation of a pertussis toxin-sensitive G protein and of phospholipase C defining a peptidergic triggering pathway of mast cells.