Koyama S, Garcia J G, Rennard S I, Robbins R A
First Department of Internal Medicine, Shinshu University School of Medicine, Matsumoto, Japan.
Am J Respir Cell Mol Biol. 1995 Sep;13(3):366-75. doi: 10.1165/ajrcmb.13.3.7654391.
In the present investigation, we evaluated the roles of calcium, calcium-calmodulin, inositol turnover, and protein kinase C in the release of lipoxygenase-derived metabolites with neutrophil chemotactic activity (NCA) from bronchial epithelial cells (BECs) in response to endotoxin (ETX) and opsonized zymosan (OZ). Both ETX and OZ stimulated BECs to release NCA [56.9 +/- 5.1 (ETX), 65.2 +/- 5.1 (OZ) versus 15.2 +/- 3.0 (controls) cells/high power field, P < 0.001]. The lipoxygenase inhibitors, nordihydroguaiaretic acid and diethylcarbamazine, and phospholipase A2 inhibitors, mepacrine and dibucaine, blocked the release of NCA in response to ETX, OZ, calcium ionophore A23187 (A23187), and phorbol myristate acetate (PMA). The calcium channel blockers, nifedipine and verapamil, and two putative inhibitors of calcium release from intracellular storage sites, 8-(N,N-diethylamine)-octyl-3,4,5-trimethoxybenzoate hydrochloride and ruthenium red, inhibited the release of NCA induced by ETX but had little effect on the release of NCA induced by OZ. However, depletion of extracellular calcium inhibited the release of NCA in response to both ETX and OZ. Calmodulin inhibitors, compound 48/80 and N-(6-aminohexyl)-1 naphthalenesulfonamide (W-7), inhibited the release of NCA in response to a variety of endotoxin concentrations. Lithium chloride, an inositol turnover inhibitor, inhibited the release of NCA in response to both ETX and OZ, but less attenuation was observed in the response to OZ. A protein kinase C inhibitor, dihydrosphingosine, inhibited the release of NCA in response to both ETX and OZ. Finally, A23187 and PMA stimulated the release of NCA and [3H]arachidonic acid independently and additively. These data suggest that the release of NCA from BECs in response to OZ may be predominantly mediated by inositol turnover and protein kinase C and that the release of NCA in response to ETX may be regulated by calcium influx and calcium release from intracellular storage sites, calcium-calmodulin activation, inositol turnover, and protein kinase C activation. Protein kinase C augmented the release of NCA and [3H]arachidonic acid independent of and in combination with calcium. These results may suggest the calcium and protein kinase C dependency of the release of NCA from BECs.
在本研究中，我们评估了钙、钙调蛋白、肌醇代谢及蛋白激酶C在支气管上皮细胞（BECs）响应内毒素（ETX）和调理酵母聚糖（OZ）释放具有中性粒细胞趋化活性（NCA）的脂氧合酶衍生代谢产物中的作用。ETX和OZ均刺激BECs释放NCA[56.9±5.1（ETX），65.2±5.1（OZ）对比15.2±3.0（对照）个细胞/高倍视野，P<0.001]。脂氧合酶抑制剂去甲二氢愈创木酸和乙胺嗪，以及磷脂酶A2抑制剂米帕林和丁卡因，可阻断BECs响应ETX、OZ、钙离子载体A23187（A23187）和佛波醇肉豆蔻酸酯乙酸酯（PMA）释放NCA。钙通道阻滞剂硝苯地平和维拉帕米，以及两种推测的细胞内钙释放抑制剂盐酸8-（N，N-二乙胺）-辛基-3,4,5-三甲氧基苯甲酸酯和钌红，可抑制ETX诱导的NCA释放，但对OZ诱导的NCA释放影响较小。然而，细胞外钙耗尽可抑制BECs响应ETX和OZ释放NCA。钙调蛋白抑制剂48/80化合物和N-（6-氨基己基）-1-萘磺酰胺（W-7），可抑制不同内毒素浓度下NCA的释放。肌醇代谢抑制剂氯化锂，可抑制BECs响应ETX和OZ释放NCA，但对OZ响应的抑制作用较小。蛋白激酶C抑制剂二氢鞘氨醇，可抑制BECs响应ETX和OZ释放NCA。最后，A23187和PMA分别独立且相加地刺激NCA和[3H]花生四烯酸的释放。这些数据表明，BECs响应OZ释放NCA可能主要由肌醇代谢和蛋白激酶C介导，而响应ETX释放NCA可能受钙内流、细胞内钙释放、钙-钙调蛋白激活、肌醇代谢和蛋白激酶C激活的调节。蛋白激酶C可独立于钙并与钙协同增强NCA和[3H]花生四烯酸的释放。这些结果可能提示BECs释放NCA对钙和蛋白激酶C的依赖性。
