Histamine release from mast cells and basophils

"Histamine release from mast cells and basophils" refers to a **cellular process**, not a specific molecular target. Mast cells and basophils are immune cells that store large amounts of histamine in cytoplasmic granules. Upon activation—typically by allergens binding to IgE on FcεRI receptors—these cells rapidly exocytose their granule contents, releasing histamine along with other mediators such as leukotrienes and cytokines[2][3][7]. The released histamine acts on four types of G protein-coupled receptors (H1R–H4R), leading to effects such as vasodilation, increased vascular permeability, smooth muscle contraction, pruritus, and recruitment of additional immune cells[2][3][6]. This process underlies the symptoms seen in allergic reactions including urticaria, rhinitis, asthma exacerbations, and anaphylaxis[5][6]. While drugs like antihistamines target the downstream effects by blocking H1 or H2 receptors—and some agents stabilize the cellular membrane to prevent mediator release—the "release" itself is not a discrete druggable entity but rather an event resulting from complex signaling pathways within these immune effector cells[5][6]. Note: This entry does *not* correspond to a single molecule or receptor but describes an important immunological event. For structured data purposes it should be flagged as incorrect for use as a canonical therapeutic target; instead consider specifying individual targets such as "Fc epsilon RI", "Histidine decarboxylase", or specific "Histamine receptor" subtypes for actionable drug discovery information[2][3].

Other names

Mast cell degranulationBasophil degranulationHistamine secretion from mast cells/basophilsMast cell mediator release

Blockade of histamine receptors (H1R antagonists) [2][6]; Stabilization of mast cell membranes to prevent degranulation [5]