Comprehensive Analysis of Structure and Contractile Performance of Myocardium during Development

发育过程中心肌结构和收缩性能的综合分析

• 批准号: 23300172
• 负责人: SHIMIZU Juichiro
• 金额: $ 11.65万
• 依托单位: Hiroshima International University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2011
• 资助国家: 日本
• 起止时间: 2011-04-01 至 2014-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-23300172/
• 关键词: 心筋線維; 心臓; 発達; X線回折; 心筋細胞内カルシウム濃度; 左心室圧; 左心室容積; 左心室圧容積関係; PassiveStiffness; 心筋発達; ラット; 筋線維; 筋節構造

Isolated adult cardiomyocytes show rod shape with clear transverse striation pattern. However, isolated neonatal rat cardiomyocytes or induced cardiomyocytes of embryonic stem cells show star shape without clear transverse striation pattern. To analyze the development of structure of myofilament of cardiomyocytes, we performed x-ray diffraction analysis using Spring-8. We found that myofilament of neonatal rat heart had poor aligned myofilament lattice. the averaged inter filament lattice spacing was not so different during development over two weeks, deviation of interfilament lattice spacing was quite large at birth and decreased with development. We also considered how the poorly developed myofilament creates enough pressure to perfuse whole body. According to Laplace's law, small ventriclele requires small tension to create the enough pressure. Then, the well aligned myofilament can provide enough pressure even in the well developed ventricle.

分离的成年心肌细胞呈杆状，横纹清晰。而分离的乳鼠心肌细胞或胚胎干细胞诱导的心肌细胞呈星星状，无明显横纹。为了分析心肌细胞的肌丝结构的发展，我们使用Spring-8进行了X射线衍射分析。我们发现新生大鼠心肌肌丝排列不整齐。在两周以上的发育过程中，平均丝间晶格间距差异不大，初生时丝间晶格间距偏差较大，随发育而减小。我们还考虑了发育不良的肌丝如何产生足够的压力来灌注全身。根据拉普拉斯定律，小心室需要较小的张力来产生足够的压力。因此，即使在发育良好的心室中，排列良好的肌丝也可以提供足够的压力。

项目成果

Afterload dependent increasing in crossbridge formation in ejecting rat

弹射大鼠中横桥形成的后负荷依赖性增加

• 发表时间: 2013
• 作者: Yamato Tamura;Kengo Horiuchi;Takehiro Miyasaka;Juichiro Shimizu
• 通讯作者: Juichiro Shimizu

Increased Passive Stiffness of Cardiomyocytes in the Transverse Direction and Residual Actin and Myosin Cross-Bridge Formation in Hypertrophied Rat Hearts Induced by Chronic β-Adrenergic Stimulation

慢性β-肾上腺素能刺激引起的肥大大鼠心脏横向被动硬度增加以及残余肌动蛋白和肌球蛋白跨桥形成

• DOI: 10.1007/s12576-011-0181-8
• 发表时间: 2012
• 期刊: Circulation Journal
• 影响因子: 3.3
• 作者: W.S. Yoshikawa;K. Nakamura;D. Miura;J. Shimizu;K. Hashimoto;N. Kataoka;et al.
• 通讯作者: et al.

Energy for myocardial Ca2+ handling per beat increases with heart rate in excised cross-circulated canine heart

在离体的交叉循环犬心脏中，每次心跳处理心肌 Ca2 的能量随着心率的增加而增加

• 发表时间: 2014
• 期刊: Tokai J Exp Clin Med
• 作者: Kiyooka T;Oshima Y;Fujinaka W;Iribe G;Mohri S;Shimizu J
• 通讯作者: Shimizu J

Energy for Myocardial Ca2+ Handling per Beat Increases with Heart Rate in Excised Cross-circulated Canine Heart.

在离体的交叉循环犬心脏中，每次心跳心肌 Ca2 处理的能量随着心率的增加而增加。

• 发表时间: 2014
• 期刊: Tokai J Exp Clin Med.
• 作者: Kiyooka T;Oshima Y;Fujinaka W;Iribe G;Mohri S;Shimizu J.
• 通讯作者: Shimizu J.

ラット新生児の心筋六角格子発達過程についての基礎解析

新生大鼠心肌六方格子发育过程的基础分析

• 发表时间: 2011
• 作者: 竹内祐貴;中村一文;三浦大志;清水壽一郎
• 通讯作者: 清水壽一郎