Lin J, Kim Y, Less C, Ondrey F, Juhn S K
Otitis Media Research Center, Department of Otolaryngology, University of Minnesota School of Medicine, Minneapolis, USA.
Ann Otol Rhinol Laryngol. 1996 Nov;105(11):916-21. doi: 10.1177/000348949610501113.
Lipoxygenase is an enzyme that metabolizes arachidonic acid down to leukotrienes. Recent studies have shown that the enzyme is implicated in mucous glycoprotein (MGP) secretion stimulated by inflammatory mediators in the airways, suggesting its possible role in secretion of MGP from middle ear epithelial cells. To investigate a correlation between MGP secretion and the arachidonic acid metabolites, we examined the effects of nordihydroguaretic acid (NDGA, both a cyclooxygenase and lipoxygenase inhibitor), low-dose indomethacin (an inhibitor of cyclooxygenase), and A63162 (an inhibitor of lipoxygenase) on MGP secretion in cultured chinchilla middle ear epithelial cells. It was found that lipoxygenase inhibition led to reduction of MGP secretion from cultured chinchilla middle ear epithelial cells, while cyclooxygenase inhibition did not. Both cyclooxygenase and lipoxygenase inhibition resulted in profound blockage of MGP secretion in baseline and platelet activating factor-stimulated MGP secretion. It was concluded, therefore, that MGP secretion was linked to arachidonic acid metabolites, especially lipoxygenase products.
脂氧合酶是一种将花生四烯酸代谢为白三烯的酶。最近的研究表明，该酶与气道中炎症介质刺激的黏液糖蛋白（MGP）分泌有关，提示其可能在中耳上皮细胞分泌MGP中发挥作用。为了研究MGP分泌与花生四烯酸代谢产物之间的相关性，我们检测了去甲二氢愈创木酸（NDGA，一种环氧化酶和脂氧合酶抑制剂）、低剂量吲哚美辛（一种环氧化酶抑制剂）和A63162（一种脂氧合酶抑制剂）对培养的灰鼠中耳上皮细胞中MGP分泌的影响。结果发现，抑制脂氧合酶会导致培养的灰鼠中耳上皮细胞中MGP分泌减少，而抑制环氧化酶则不会。抑制环氧化酶和脂氧合酶均会导致基线状态下以及血小板活化因子刺激的MGP分泌出现严重阻滞。因此得出结论，MGP分泌与花生四烯酸代谢产物有关，尤其是脂氧合酶产物。
