Molecular mechanisms of Ca^<2+> uptake by sarcolipin in cardiac sarcoplasmic reticulum.

心脏肌浆网肌磷脂摄取Ca ^ 2 的分子机制。

• 批准号: 16500269
• 负责人: KURIHARA Satoshi
• 金额: $ 1.66万
• 依托单位: Jikei University School of Medicine
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2004
• 资助国家: 日本
• 起止时间: 2004 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-16500269/
• 关键词: Ca^<2+>; sarcoplasmic reticulum; sarcolipin; skinned preparation; saponin; mouse; cardiac muscle; Ca^<2+> transients; ウエスタンブロッティン; カルシウム; 筋小胞体Caポンプ; 細胞内Ca^<2+>

The aim of the study was to explore the role of Ca^<2+> handling-related protein, sarcolipin (SLN) for the regulation of intracellular Ca^<2+> concentration. Sarcoplasmic reticulum (SR)(SERCA2a) is regulated by phospholamban (PLB) and SLN which couple with SERCA2a. Both non-phosphorylated-PLB and -SLN decrease the Ca^<2+> uptake rate of SR. We overexpressed SLN in ventricular muscles of mouse (SLN-TG) and investigated how SERCA2a is influenced by SLN. We measured the Ca^<2+> transients and contraction in intact left ventricular papillary muscles of mouse using the aequorin method. Also, we used saponin-treated thin trabeculae to investigate Ca^<2+> uptake, Ca^<2+> release and Ca^<2+> leakage. In twitch contraction, Hz, the peaks of the Ca^<2+> transient and contraction in SLN-TG were lower than those of the control. The rate of decline of the Ca^<2+> transient and tension was slower than that of the control. In the skinned fiber, Ca^<2+> was loaded in the SR in the presence of ATP and Ca^<2+> (pCa 6.2) for various periods, and Ca^<2+> in the SR was released by caffeine. We measured the released Ca^<2+> with fluo-3. The rate of Ca^<2+> uptake in SLN-TG was slower when the Ca^<2+> loading time was short but no difference was observed when the loading time was longer. The maximal Ca^<2+> content of SR at a steady state in both TG and non-TG cardiac muscles did not differ. Ca^<2+>-induced Ca^<2+> release (CICR) in SLN-TG did not differ from that in non-TG. Ca^<2+> leakage was estimated by measuring the leaked Ca in the solution without ATP and Ca^<2+> after Ca^<2+> loading. Ca^<2+> leakage in SLN-TG was not different from that in non-TG. Thus, SLN decreases the Ca^<2+> uptake in SR and influences intracellular Ca^<2+> concentration. The role of SLN is significant in beat-to-beat contraction, but SLN does not play a significant role at a steady state.

本研究的目的是探讨Ca^2+处理相关蛋白肌磷脂(SLN)在调节细胞内Ca^2+浓度中的作用。肌浆网 (SR)(SERCA2a) 受磷蛋白 (PLB) 和与 SERCA2a 偶联的 SLN 调节。非磷酸化-PLB和-SLN均降低SR的Ca 2+ 摄取率。我们在小鼠心室肌 (SLN-TG) 中过度表达 SLN，并研究了 SERCA2a 如何受到 SLN 的影响。我们使用水母发光蛋白方法测量了小鼠完整左心室乳头肌的Ca 2+ 瞬变和收缩。此外，我们使用皂苷处理的薄小梁来研究 Ca^<2+> 吸收、Ca^<2+> 释放和 Ca^<2+> 渗漏。在抽搐收缩Hz中，SLN-TG中的Ca 2+ 瞬变和收缩的峰值低于对照。 Ca ^ 2+ 瞬时值和张力的下降速度比对照慢。在带皮纤维中，在 ATP 和 Ca ^ 2+ (pCa 6.2) 存在的情况下，Ca ^ 2+ 在不同时期加载在 SR 中，并且 SR 中的 Ca ^ 2+ 由咖啡因释放。我们用fluo-3 测量了释放的Ca^<2+>。当Ca^2+加载时间短时，SLN-TG中Ca^2+的吸收速率较慢，但当加载时间较长时，没有观察到差异。 TG和非TG心肌中稳态时SR的最大Ca 2+ 含量没有差异。 SLN-TG中Ca 2+ 诱导的Ca 2+ 释放(CICR)与非TG中没有差异。通过测量不含ATP的溶液中的泄漏Ca和Ca 2+ 加载后的Ca 2+ 来估计Ca 2+ 泄漏。 SLN-TG中的Ca 2+ 渗漏与非TG中的Ca 2+ 渗漏没有不同。因此，SLN降低SR中Ca ^ 2+ 的摄取并影响细胞内Ca ^ 2+ 浓度。 SLN 在逐次收缩中发挥重要作用，但在稳定状态下 SLN 不起重要作用。

项目成果

p38α mitogen-activated protein kinase plays a critical role in cardiomyocyte survival but not in cardiac hypertrophic growth in response to pressure overload

• DOI: 10.1128/mcb.24.24.10611-10620.2004
• 发表时间: 2004-12-01
• 期刊: MOLECULAR AND CELLULAR BIOLOGY
• 影响因子: 5.3
• 作者: Nishida, K;Yamaguchi, O;Otsu, K
• 通讯作者: Otsu, K

Targeted deletion of apoptosis signal-regulating kinase 1 attenuates left ventricular remodeling

• DOI: 10.1073/pnas.2136717100
• 发表时间: 2003-12-23
• 期刊: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• 影响因子: 11.1
• 作者: Yamaguchi, O;Higuchi, Y;Otsu, K
• 通讯作者: Otsu, K

Comparative effects of bupivacaine and ropivacaine on intracellular calcium transients and tension in ferret ventricular muscle

布比卡因和罗哌卡因对雪貂心室肌细胞内钙瞬变和张力的比较影响

• 发表时间: 2004
• 期刊: Anesthesiology 101(4)
• 作者: Mio Y