Involvement of Src family protein tyrosine kinases in Ca2+ sensitization of coronary artery contraction mediated by a sphingosylphosphorylcholine-Rho-kinase pathway
Involvement of Src family protein tyrosine kinases in Ca2+ sensitization of coronary artery contraction mediated by a sphingosylphosphorylcholine-Rho-kinase pathway
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DOI：
10.1161/01.res.0000042702.04920.bf
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发表时间：
2002-11-15
影响因子：
20.1
通讯作者：
Matsuzaki, M
中科院分区：
文献类型：
--
作者：
Nakao, F;Kobayashi, S;Matsuzaki, M
我们最近报道，鞘氨醇磷酸胆碱（SPC）是一种新的信使Rho激酶介导的Ca ~（2+）敏化血管平滑肌（VSM）收缩。Src家族蛋白激酶（SrcPTKs）的亚细胞定位和激酶活性，除了c-Src，是由可逆的S-棕榈酰化，二十碳五烯酸（EPA）抑制的事件控制。我们研究了SrcPTKs可能参与SPC诱导的Ca 2+敏化和EPA的影响。我们使用猪冠状动脉VSM和大鼠主动脉VSM细胞（VSMCs）在原代培养。SrcPTKs抑制剂PP 1和EPA浓度依赖性地抑制SPC诱导的收缩，而不影响[Ca 2 +]（i）水平和高K+去极化诱导的Ca 2+依赖性收缩。VSMCs的数字化免疫细胞化学分析显示，SPC诱导Fyn易位，但不是c-Src，从细胞质到细胞膜，EPA废除的事件。转运的Rho激酶从胞质溶胶到细胞膜的SPC也被EPA和PP 1抑制。SPC诱导的SrcPTKs激活被EPA和PP 1阻断，但不被Rho激酶抑制剂Y27632阻断。EPA、PP 1和Y27632抑制SPC诱导的肌球蛋白磷酸酶的Rho激酶依赖性磷酸化。SrcPTKs（包括Fyn）的易位和激活在由SPC-Rho-激酶途径介导的VSM收缩的Ca 2+敏化中起重要作用。
We recently reported that sphingosylphosphorylcholine (SPC) is a novel messenger for Rho-kinase-mediated Ca2+ sensitization of vascular smooth muscle (VSM) contraction. Subcellular localization and kinase activity of Src family protein kinases (SrcPTKs), except for c-Src, is controlled by a reversible S-palmitoylation, an event inhibited by eicosapentaenoic acid (EPA). We examined the possible involvement of SrcPTKs in SPC-induced Ca2+ sensitization and effects of EPA. We used porcine coronary VSM and rat aortic VSM cells (VSMCs) in primary culture. An SrcPTKs inhibitor, PP1, and EPA inhibited SPC-induced contraction, concentration-dependently, without affecting [Ca2+](i) levels and the Ca2+-dependent contraction induced by high K+ depolarization. A digitized immunocytochemical analysis in VSMCs revealed that SPC induced translocation of Fyn, but not of c-Src, from the cytosol to the cell membrane, an event abolished by EPA. Translocation of Rho-kinase from the cytosol to the cell membrane by SPC was also inhibited by EPA and PP1. The SPC-induced activation of SrcPTKs was blocked by EPA and PP1, but not by Y27632, an Rho-kinase inhibitor. Rho-kinase-dependent phosphorylation of myosin phosphatase induced by SPC was inhibited by EPA, PP1, and Y27632. Translocation and activation of SrcPTKs, including Fyn, play an important role in Ca2+ sensitization of VSM contractions mediated by a SPC-Rho-kinase pathway.