Role of cysteinyl leukotriene receptor antagonists in the management of allergic rhinitis

Abstract

The cysteinyl leukotrienes (CysLTs) are lipid mediators that have been implicated in the pathogenesis of allergic diseases. Pharmacological studies using CysLTs indicate that there exist two classes of receptors named CysLT₁ and CysLT₂. The former is sensitive to CysLT₁ receptor antagonists currently used for the treatment of asthma and allergic rhinitis. Our previous immunohistochemical and autoradiographic studies showed that anti-CysLT₁ receptor antibody adhered to eosinophils, mast cells, macrophages, neutrophils, and vascular endothelial cells in human nasal mucosa, and that a novel radioactive CysLT₁ receptor antagonist, [³H]-pranlukast, bound specifically to CysLT₁ receptors in human inferior turbinate and its binding sites were localized to vascular endothelium and interstitial cells. These data suggest that in allergic rhinitis, the major targets of CysLT₁ receptor antagonists are the vascular bed and infiltrating leucocytes such as mast cells, eosinophils, and macrophages. Clinical trials have demonstrated that CysLT₁ receptor antagonists are as effective as antihistamines, but are less effective than intranasal steroids for the treatment of allergic rhinitis. The use of CysLT₁ receptor antagonists in combination with antihistamines has generally resulted in greater efficacy than when these agents were used alone.