A new intracellular foctor for regulation of Ca channel.

一种新的细胞内钙离子通道调节因子。

• 批准号: 09670051
• 负责人: KAMEYAMA Masaki
• 金额: $ 1.98万
• 依托单位: Kagoshima University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09670051/
• 关键词: Ca channel; calpastatin; patch clamp; cardiac myocytes; 心筋; カルシウムチャネル

Voltage-operated L-type Ca^<2+> channels play important roles in cellular excitation related to rhythmic firing, synaptic transmission, muscle contraction and secretion. However, run-down of the Ca^<2+> channel has been an obstacle to studies of the channel. We have been investigating the mechanism of run-down in relation to the understanding of the regulation of channel activity. We have suggested previously that cytoplasmic factors are involved in maintenance of channel activity, and that wash-out of the factors is the cause of run-down. The properties of one possible factor in cytoplasm resemble those of calpastatin, an endogenous inhibitor of Ca-activated neutral protease. However, fractionated cytoplasm or purified calpastatin shows a limited ability to recover channel activity. This implied that there might be other co-factor(s). Therefore, this study was carried out to elucidate the nature of the cytoplasmic factors. It was found that another protein-like factor, together with calpastatin and ATP, restores L-type Ca^<2+> channel activity.

电压操纵的L-型Ca^<2+>通道在细胞节律性放电、突触传递、肌肉收缩和分泌等细胞兴奋过程中起重要作用。然而，Ca^<2+>通道的衰竭一直是该通道研究的障碍。我们一直在研究与了解通道活动的调节有关的运行机制。我们以前曾提出，细胞质因子参与维持通道活性，而这些因子的洗脱是导致通道衰竭的原因。细胞质中的一个可能的因子的性质类似于钙蛋白酶抑制剂，钙激活的中性蛋白酶的内源性抑制剂。然而，分级分离的细胞质或纯化的钙蛋白酶抑制蛋白显示出有限的恢复通道活性的能力。这意味着可能还有其他辅因素。因此，本研究旨在阐明细胞质因子的性质。研究发现，另一种蛋白质样因子与钙蛋白酶抑制蛋白和ATP一起恢复L型Ca^2+通道活性。

项目成果

Kameyama,A.: "Characterization and partial purification of the cytoplasmic factor that maintains cardiac Ca^<2+> channel activity" Pflugers Arch.Eur.J.Physiol.435. 338-343 (1998)

Kameyama,A.：“维持心脏 Ca^2 通道活性的细胞质因子的表征和部分纯化”Pflugers Arch.Eur.J.Physiol.435。

Kameyama A: "Run-down of the cardiac Ca^<2+> channel : Characterization and restoration of channel activity by cytoplasmic factors." Pflugers Arch. 433. 547-556 (1997)

Kameyama A：“心脏 Ca^2 通道的衰退：细胞质因子对通道活性的表征和恢复。”

Kameyama,M.: "Run-down of the cardiac L-type Ca^<2+> channel : partial restoration of channel activity in cell-free patches by calpastatin" Pflugers Arch.Eur.J.Physiol. 435. 344-349 (1998)

Kameyama,M.：“心脏 L 型 Ca^2 通道的耗尽：通过钙蛋白酶抑制素部分恢复无细胞斑块中的通道活性”Pflugers Arch.Eur.J.Physiol。

Kameyama,A.: "Characterization and partial purification of the cytoplasmic factor that maintains cardiac Ca^2 channel activity" Pflugers Arch.Eur.J.Physiol. 435. 338-343 (1998)

Kameyama,A.：“维持心脏 Ca^2 通道活性的细胞质因子的表征和部分纯化”Pflugers Arch.Eur.J.Physiol。

Kameyama A,Hao L-Y,Takano E & Kameyama M: "Characterization and partial purification of the cytoplasmic factor that maintaints cardiac Ca^<2+> channel activity." Pflugers Arch. 435. 338-343 (1998)

龟山A,郝L-Y,高野E