Role of glycolytically generated ATP for CaMKII-mediated regulation of intracellular Ca2+ signaling in bovine vascular endothelial cells
Role of glycolytically generated ATP for CaMKII-mediated regulation of intracellular Ca2+ signaling in bovine vascular endothelial cells
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DOI：
10.1152/ajpcell.00543.2006
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发表时间：
2007-07-01
影响因子：
5.5
通讯作者：
Blatter, Lothar A.
中科院分区：
文献类型：
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作者：
Aromolaran, Ademuyiwa S.;Zima, Aleksey V.;Blatter, Lothar A.
在体外培养的小牛肺动脉内皮细胞(CPAE)上，研究了糖酵解产生的ATP在钙/钙调素依赖的激酶II(CaMKII)介导的细胞内钙信号调节中的作用。用糖酵解抑制剂2-脱氧-D-葡萄糖(2-DG)、丙酮酸(PYR)+β-羟丁酸酯(β-Hb)或碘乙酸(IAA)处理细胞(细胞外钙浓度=2 mM)可引起细胞内钙浓度([Ca~(2+)](I))升高。CaMKII抑制剂(KN-93、W-7)可引起类似的[Ca~(2+)](I)升高。[Ca~(2+)](I)升高的特征是短暂的峰值，然后是一个小的持续平台升高的[Ca~(2+)](I)。在没有细胞外钙离子的情况下，2-DG引起[Ca~(2+)](I)的增加，提示糖酵解的抑制直接触发了细胞内内质网(ER)内钙的释放。肌醇-1，4，5-三磷酸受体(IP3R)抑制剂2-氨基乙氧基二苯硼酸酯可阻断KN-93-和2-DG诱导的钙反应。Ca~(2+)的释放是在外周胞浆过程中启动的，激活以[Ca~(2+)](I)波的形式向细胞的中心区传播。焦点应用2-DG导致空间受限的[Ca~(2+)](I)升高。在传播[Ca~(2+)](I)波之前，有[Ca~(2+)](I)振荡和[Ca~(2+)](I)(Ca~(2+))的小而高度的局部升高。用2-DG抑制糖酵解可降低KN-93诱导的Ca~(2+)反应，而在抑制CaMKII_2-DG诱导的Ca~(2+)释放时，则相反。PYR+β-Hb和W-7也得到了类似的结果。此外，2-DG和IAA引起细胞内镁离子浓度迅速升高，表明细胞内ATP水平随之下降。综上所述，CaMKII对CPAE细胞的内质网钙释放有明显的抑制作用，这种抑制作用是通过糖酵解产生的三磷酸腺苷，可能是通过三磷酸腺苷依赖的IP3R的磷酸化来实现的。
The role of glycolytically generated ATP in Ca2+/calmodulin-dependent kinase II (CaMKII)-mediated regulation of intracellular Ca2+ signaling was examined in cultured calf pulmonary artery endothelial (CPAE) cells. Exposure of cells (extracellular Ca2+ concentration = 2 mM) to glycolytic inhibitors 2-deoxy-D-glucose (2-DG), pyruvate (pyr) + beta-hydroxybutyrate beta-HB), or iodoacetic acid (IAA) caused an increase of intracellular Ca2+ concentration ([Ca2+](i)). CaMKII inhibitors (KN-93, W-7) triggered a similar increase of [Ca2+](i). The rise of [Ca2+](i) was characterized by a transient spike followed by a small sustained plateau of elevated [Ca2+](i). In the absence of extracellular Ca2+ 2-DG caused an increase in [Ca2+](i), suggesting that inhibition of glycolysis directly triggered release of Ca2+ from intracellular endoplasmic reticulum (ER) Ca2+ stores. The inositol-1,4,5-trisphosphate receptor (IP3R) inhibitor 2-aminoethoxydiphenyl borate abolished the KN-93- and 2-DG-induced Ca2+ response. Ca2+ release was initiated in peripheral cytoplasmic processes from which activation propagated as a [Ca2+](i) wave toward the central region of the cell. Focal application of 2-DG resulted in spatially confined elevations of [Ca2+](i). Propagating [Ca2+](i) waves were preceded by [Ca2+](i) oscillations and small, highly localized elevations of [Ca2+](i) (Ca2+ puffs). Inhibition of glycolysis with 2-DG reduced the KN-93- induced Ca2+ response, and vice versa during inhibition of CaMKII 2-DG-induced Ca2+ release was attenuated. Similar results were obtained with pyr + beta-HB and W-7. Furthermore, 2-DG and IAA caused a rapid increase of intracellular Mg2+ concentration, indicating a concomitant drop of cellular ATP levels. In conclusion, CaMKII exerts a profound inhibition of ER Ca2+ release in CPAE cells, which is mediated by glycolytically generated ATP, possibly through ATP-dependent phosphorylation of the IP3R.