piriprost (u 60257) is a leukotriene synthesis inhibitor [1].leukotrienes belong to a family of eicosanoid inflammatory mediators produced in leukocytes. leukotrienes mainly act on a subfamily of g protein-coupled receptors. the production of leukotrienes is implicated in triggerring contractions in the smooth muscles lining the bronchioles and is a major cause of inflammation in asthma and allergic rhinitis [2].piriprost inhibited the formation of 5-hydroxyeicosatetraenoic acid (5-hete), ltb4, and the sulfidopeptide leukotrienes with the ic50 values ranged from 9 to 14 μm for the mouse mast cells and 15-50 μm for the basophil leukemia cells. piriprost weakly inhibited the solubilized ltc synthase of rat basophil leukemia cells with the ic50 of 1.5 mm [1]. piriprost increased alkaline phosphatase (alp) activity in cultured endometrial stromal cells. piriprost (100 μm) inhibited 5-lipoxygenase activity and decreased 5-hydroxy-eicosatetraenoic acid (a 5-lipoxygenase product) by 53% [3].in smoke-exposed rabbits, pretreatment with piriprost attenuated the smoke-induced increase in alveolar-capillary barrier permeability and decrease in plasminogen activator activity and causes a swelling of type i alveolar epithelium [4].
[1] bach m k, brashler j r, white g j, et al. experiments on the mode of action of piriprost (u-60,257), an inhibitor of leukotriene formation in cloned mouse mast cells and in rat basophil leukemia cells[j]. biochemical pharmacology, 1987, 36(9): 1461-1466.
[2] smith m j h, ford‐hutchinson a w, bray m a. leukotriene b: a potential mediator of inflammation[j]. journal of pharmacy and pharmacology, 1980, 32(1): 517-518.
[3] cejic s s, kennedy t g. examination of the effects of piriprost (u-60,257 b) on alkaline phosphatase activity of rat endometrial stromal cells in vitro[j]. prostaglandins, 1991, 42(2): 179-189.
[4] itten m l, grad r, quan s f, et al. piriprost pretreatment attenuates the smoke-induced increase in 99mtcdtpa lung clearance[j]. experimental lung research, 1990, 16(4): 339-353.
