Are the leukotrienes involved in the bronchial asthma?

The discovery of chemical structure of a new group of biologically active molecules, previously indicated as slow-reacting substance of anaphylaxis /SRS-A/ and their synthesis enabled the studies of their effects in isolated tissues as well as in vivo. It has showed that leukotrienes C4, D4 and E4 have a special affinity to lung tissue. They increased the tonus of the airway smooth muscles, increased the insuflation pressure in guinea-pigs, increased the transpulmonary pressure in monkeys, and impaired the human respiratory functions. Moreover, leukotriene B4 increased the adhesion of leukocytes to endothelial cells, stimulated the chemotaxis and chemokinesis of polymorphonuclear leukocytes, stimulated the degranulation and release of lysosomal enzymes from human and rabbit polymorphonuclear leukocytes, and increased the calcium mobilization in rabbit's neutrophils. All these effects contribute ot the edema of the bronchial epithelium and potentiate and prolong the asthmatic attac. It seems therefore that the study of leukotrienes and their antagonists could attribute to the progress in the treatment of bronchial asthma.