Leukotriene receptors (BLTR/CysLTR)

EPA-derived 5-series leukotrienes (LTB5, LTC5, LTD5, and LTE5) are inflammatory mediators synthesized from the omega-3 fatty acid eicosapentaenoic acid (EPA) via the 5-lipoxygenase pathway. These molecules exert their biological effects by binding to the same G protein-coupled receptors as the more potent arachidonic acid-derived 4-series leukotrienes, specifically the leukotriene B4 receptors (BLT1 and BLT2) and the cysteinyl leukotriene receptors (CysLT1 and CysLT2) (PMID: 15507361). A key characteristic of 5-series leukotrienes is their significantly lower affinity and reduced biological activity—often 10- to 100-fold less potent—compared to the 4-series (PMID: 10660115). By competing for the same receptor binding sites, 5-series leukotrienes act as functional antagonists or weak agonists, which is a primary mechanism underlying the anti-inflammatory effects of omega-3 fatty acid supplementation (PMID: 12444825). These receptors are critical therapeutic targets in inflammatory and respiratory diseases. For instance, CysLT1 antagonists like montelukast are widely used to treat asthma and allergic rhinitis by blocking the effects of both 4-series and 5-series cysteinyl leukotrienes (PMID: 17324660).

Other names

BLT1BLT2CysLT1CysLT2Leukotriene B4 receptorCysteinyl leukotriene receptorLTB5 receptor5-series leukotriene receptors

Competitive antagonism of G protein-coupled receptors (BLT and CysLT) to inhibit the pro-inflammatory and bronchoconstrictive effects of leukotrienes.