[Leukotrienes: their significance in the pathogenesis of asthma].

Cysteinyl leukotrienes (cys-LT) are potent spasmogenic agents, increase markedly vascular permeability and mucus secretion and promote intense recruitment, with activation, of inflammatory cells into the airways, increasing bronchial responsiveness. An augmented release of cys-LT from bronchopulmonary tissues has been demonstrated in spontaneous asthma and in many obstructive reactions to allergic and non-allergic stimuli. Finally some cys-LT antagonists and LT synthesis inhibitors have shown remarkable acute anti-reactive activity and good clinical efficacy. All these findings point to an important pathogenetic role of cys-LT in bronchial asthma.