Cysteinyl leukotriene receptors.

Cysteinyl leukotrienes (CysLTs) are important inflammatory mediators in asthma and allergic disorders. Two types of CysLT receptors, CysLT(1) and CysLT(2), which were originally defined pharmacologically based on their sensitivity to CysLT(1) specific antagonists, are responsible for most of the known CysLT biological actions. The regulation of CysLT receptor expression and signaling in disease processes is largely unclear. Recent molecular cloning of both receptor subtypes from several different species will greatly facilitate future research in understanding CysLT signal transduction mechanisms. Expression of the relatively better-studied CysLT(1) is verified in lung tissues and peripheral blood cells. Elucidating how this receptor mediates airway inflammation will deepen our understanding of asthma etiology. On the other hand, detection of CysLT(2) in the heart, brain, and adrenal glands will inject new excitement into the search for novel CysLT functions. This review summarizes receptor cloning, ligand binding, expression, signaling, and functions in an effort to bridge early pharmacological studies to future studies at the molecular level.