Isivas Mechanism of Action

Pharmacology: Mechanism of Action: The cysteinyl leukotrienes (LTC4, LTD4, LTE4) are potent inflammatory eicosanoids released from various cells including mast cells and eosinophils. These important pro-ashmatic mediators bind to cysteinyl leukotriene (CysLT) receptors. The CysLT type-1 (CysLT), receptor is found in the human airway (including airway smooth muscle cell and airway macrophage) and on other pro-inflamatory cells (including eosinophils and certain myeloid stem cells). CysLTs have been correlated with the pathophysiology of asthma. In asthma, leukotriene-mediated effects include a number of airway actions, including bronchoconstriction, mucous secretion, vascular permeability and eosinophil recruitment.
Montelukast is orally active compound that significantly improves parameters of asthmatic inflammation. Based on biochemical and pharmacological bioassays, it binds with high affinity and selectivity to the CysLT₁ receptor (in preference to other pharmacologically important airway receptors such as the prostanoid, cholinergic, or β-adrenergic receptor). Montelukast potently inhibits physiologic actions of LTC₄, LTD₄ and LTE₄ at the CysLT₁ receptor without any agonist activity.