Role of eicosanoids in vasopressin-induced calcium mobilization in A7r5 vascular smooth muscle cells.
Role of eicosanoids in vasopressin-induced calcium mobilization in A7r5 vascular smooth muscle cells.
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类二十烷酸在加压素诱导的 A7r5 血管平滑肌细胞钙动员中的作用。
DOI：
10.1152/ajpendo.1993.265.1.e108
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Simonson,MS
中科院分区：
文献类型：
--
作者：
Thibonnier,M;Bayer,AL;Laethem,CL;Koop,DR;Simonson,MS
应用细胞内钙监测、[14C]AA标记和高效液相色谱(HPLC)技术，探讨花生四烯酸(AA)及其代谢产物在加压素(AVP)诱导的A7r5血管平滑肌细胞钙动员中的作用。在Fura-2负载的A7r5细胞中，AA增强了AVP刺激的细胞内游离钙([Ca+]i)的增加。环氧合酶抑制剂吲哚美辛可减少AA和AVP诱导的细胞外钙内流。AVP诱导的[Ca~(2+)]i瞬变不被脂氧合酶抑制剂改变，但被细胞色素P-450单加氧酶抑制剂酮康唑以剂量依赖的方式减少。在AA的几种环氧酶代谢产物中，5，6-环氧二十碳三烯酸增强了AVP诱导的[Ca~(2+)]i瞬变。用[14C]AA预先标记的A7r5细胞的脂类提取物的反相高效液相分析分离到一个放射性峰，该峰不与环氧合酶、脂氧合酶或细胞色素P-450催化的AA氧化的已建立的产物协同洗脱。此峰在AVP刺激后显著增加，并被酮康唑预孵育完全阻断。因此，刺激A7r5细胞的V1血管AVP受体可通过环氧合酶和环氧合酶途径触发涉及AA代谢物形成的几条细胞质信号通路。
The role of arachidonic acid (AA) and its metabolites in vasopressin (AVP)-induced calcium mobilization in A7r5 aortic smooth muscle cells was explored by intracellular calcium monitoring, [14C]AA labeling, and high-performance liquid chromatography (HPLC) techniques. In fura 2-loaded A7r5 cells, AA potentiated AVP-stimulated increase in intracellular free Ca2+ ([Ca2+]i). The cyclooxygenase inhibitor indomethacin reduced both the AA- and AVP-induced influx of extracellular Ca2+. AVP-induced [Ca2+]i transients were not altered by lipoxygenase inhibitors but were reduced in a dose-dependent fashion by ketoconazole, an inhibitor of cytochrome P-450 monooxygenases. Among several epoxygenase metabolites of AA tested, 5,6-epoxyeicosatrienoic acid potentiated AVP-induced [Ca2+]i transients. Reverse-phase HPLC analysis of lipid extracts from A7r5 cells prelabeled with [14C]AA isolated a radioactive peak that did not coelute with established products of cyclooxygenase-, lipoxygenase-, or cytochrome P-450-catalyzed oxidations of AA. This peak was significantly increased after AVP stimulation and was completely blocked by preincubation with ketoconazole. Thus the stimulation of V1-vascular AVP receptors of A7r5 cells triggers several cytoplasmic signaling pathways involving AA metabolite formation through the cyclooxygenase and epoxygenase pathways.