Role of Ca2+/calmodulin-dependent protein kinase II in the regulation of the cardiac L-type Ca2+ current during endothelin-1 stimulation
Role of Ca2+/calmodulin-dependent protein kinase II in the regulation of the cardiac L-type Ca2+ current during endothelin-1 stimulation
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DOI：
10.1152/ajpheart.01141.2009
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发表时间：
2010-06-01
影响因子：
4.8
通讯作者：
Kurihara, Satoshi
中科院分区：
文献类型：
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作者：
Komukai, Kimiaki;O-Uchi, Jin;Kurihara, Satoshi
[10]张文，张文. Ca 2 +/钙调素依赖性蛋白激酶II在内皮素-1刺激期间调节心脏L型Ca 2+电流中的作用。Am J Physiol Heart Circ Physiol 298：H1902-H1907，2010.首次发表于2010年3月19日; doi：10.1152/ajpheart.01141.2009.-内皮素-1（ET-1）对心肌具有正性肌力作用。虽然L型钙电流（I-Ca）是心脏兴奋-收缩耦联的重要决定因素之一，但ET-1对I-Ca的影响尚不清楚。有争议的结果似乎是由于不同的膜片钳方法。采用穿孔膜片钳技术观察了内皮素-1对大鼠心室肌细胞钙电流的影响。保持电位设定为-40 mV，每10 s施加一次去极化。ET-1（10 nM）以双相方式增加I-Ca。当进行测量时，在施加ET-1后15分钟，电流达到稳定状态。内皮素受体亚型的表达也进行了研究，使用Western免疫印迹。大鼠心室肌细胞膜有ETA受体蛋白表达，而ETB受体蛋白不表达。选择性ETA受体拮抗剂BQ-123可抑制ET-1对I-Ca的影响，而选择性ETB受体拮抗剂BQ-788则不能抑制ET-1对I-Ca的影响。蛋白激酶C（PKC）抑制剂白屈菜红碱和Ca 2 +/钙调蛋白依赖性蛋白激酶II（CaMKII）抑制剂KN-93抑制这种作用，但不被其无活性类似物KN-92抑制。ET-1的作用也被另一种CaMK Ⅱ抑制剂autocamtide-2相关抑制肽阻断。这些结果表明，ET-1通过ETA-受体-PKC-CaMK Ⅱ途径增加I-Ca。
Komukai K, O-Uchi J, Morimoto S, Kawai M, Hongo K, Yoshimura M, Kurihara S. Role of Ca2+/calmodulin-dependent protein kinase II in the regulation of the cardiac L-type Ca2+ current during endothelin-1 stimulation. Am J Physiol Heart Circ Physiol 298: H1902-H1907, 2010. First published March 19, 2010; doi:10.1152/ajpheart.01141.2009.-Endothelin-1 (ET-1) shows a positive inotropic effect on cardiac muscle. Although the L-type Ca2+ current (I-Ca) is one of the important determinants of cardiac excitation-contraction coupling, the effect of ET-1 on the I-Ca is not always clear. The controversial results appear to be due to different patch-clamp methods. The present study measured the effect of ET-1 on the I-Ca of rat ventricular myocytes using the perforated patch-clamp technique. The holding potential was set to -40 mV, and depolarization was applied every 10 s. ET-1 (10 nM) increased the I-Ca in a monophasic manner. The current reached a steady state 15 min after the application of ET-1, when the measurement was done. Endothelin receptor subtype expression was also investigated using Western immunoblotting. ETA-receptor protein was expressed, but ETB-receptor protein was not expressed, in the cell membranes of rat ventricular myocytes. The effect of ET-1 on the I-Ca was inhibited by a selective ETA-receptor antagonist, BQ-123, but not by a selective ETB-receptor antagonist, BQ-788. The effect was inhibited by protein kinase C (PKC) inhibitor chelerythrine and Ca2+/calmodulin-dependent protein kinase II (CaMKII) inhibitor KN-93, but not by its inactive analog KN-92. The effect of ET-1 was also blocked by another CaMKII inhibitor, autocamtide-2-related inhibitory peptide. These results suggest that ET-1 increases the I-Ca via the ETA-receptor-PKC-CaMKII pathway.