Bromoenol lactone

Bromoenol lactone ((6E)-Bromoenol lactone) is a suicide-based irreversible, selective, potent inhibitor of calcium-independent phospholipase A₂ (iPLA₂β) with an IC₅₀ value of approximately 7 μM, which inhibits antigen-stimulated mast cell exocytosis without blocking Ca²⁺ influx^[1][2]. In Vitro: In RBL 2H3 and bone marrow-derived mast cells (BMMCs), Ca²⁺ entry is critical for exocytosis. Bromoenol lactone inhibits exocytosis when stimulated using a Ca²⁺ ionophore A23187, which passively transports Ca²⁺ down a concentration gradient and also in permeabilised mast cells where Ca²⁺ entry is no longer relevant. Moreover, Bromoenol lactone has only a minor effect on antigen- or thapsigargin-stimulated Ca²⁺ signalling, both the release from internal stores and sustained elevation due to Ca²⁺ influx^[1].