Effect of dephosphorylation of troponin I on arrhythmogenesis in failing hearts

2010 Fiscal Year Final Research Report

• Project/Area Number: 20590205
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: General physiology
• Research Institution: Tohoku University
• Principal Investigator: MIURA Masahito Tohoku University, 大学院・医学系研究科, 准教授 (30302110)
• Project Period (FY): 2008 – 2010
• Keywords: 病態生理 / カルシウム

Research Abstract

An increase in the affinity of the myofilaments for Ca^<2+> by lengthening the muscle or applying a Ca^<2+> sensitizer for myofilaments sustained triggered arrhythmias and increased their frequency in intact cardiac muscle. In failing hearts, dephosphorylation of troponin-I and an increase in Ca^<2+> sensitivity of the sarcoplasmic reticulum Ca^<2+> release channel increased the velocity of Ca^<2+> 2+ waves and the amplitude of delayed afterdepolarizations, thereby causing arrhythmogenesis. The affinity of the myofilaments for Ca^<2+> plays an important role in the occurrence of arrhythmias.

Research Products

• [Journal Article] Acceleration of Ca^<2+> waves in monocrotaline-induced right ventricular hypertrophy in the rat. (2011)
  • Author(s): Miura M, Hirose M, Endoh H, Wakayama Y, Sugai Y, Nakano M, Fukuda K, Shindoh C, Shirato K, himokawa H.
  • Journal Title: Circ J 75 Pages: 1343-1349
  • Peer Reviewed
• [Journal Article] Effect of non-uniform muscle contraction on sustainability and frequency of triggered arrhythmias in rat cardiac muscle. (2010)
  • Author(s): Miura M, Nishio T, Hattori T, Murai N, Stuyvers BD, Shindoh C, Boyden PA.
  • Journal Title: Circulation 121 Pages: 2711-2717
  • Peer Reviewed
• [Journal Article] Contribution of Na^+/Ca^<2+> exchange current to the formation of delayed afterdepolarizations in intact rat ventricular muscle. (2009)
  • Author(s): Sugai Y, Miura M, Hirose M, Wakayama Y, Endoh H, Nishio T, Watanabe J, ter Keurs HE, Shirato K, Shimokawa H.
  • Journal Title: J Cardiovasc Pharmacol. 53 Pages: 517-522
  • Peer Reviewed
• [Journal Article] Spatial non-uniformity of excitation-contraction coupling can enhance arrhythmogenic delayed afterdepolarizations in rat cardiac muscle. (2008)
  • Author(s): Miura M, Wakayama Y, Endoh H, Nakano M, Sugai Y, Hirose M, ter Keurs HEDJ, Shimokawa H.
  • Journal Title: Cardiovasc Res 80 Pages: 55-61
  • Peer Reviewed
• [Journal Article] Sarcomere mechanics in uniform and non-uniform cardiac muscle : A link between pump function and arrhythmias. (2008)
  • Author(s): ter Keurs HE, Shinozaki T, Zhang YM, Zhang ML, Wakayama Y, Sugai Y, Kagaya Y, Miura M, Boyden PA, Stuyvers BD, Landesberg A.
  • Journal Title: Prog Biophys Mol Biol. 97 Pages: 312-331
  • Peer Reviewed
• [Journal Article] Sarcomere mechanics in uniform and nonuniform cardiac muscle : a link between pump function and arrhythmias. (2008)
  • Author(s): ter Keurs HE, Shinozaki T, Zhang YM, Wakayama Y, Sugai Y, Kagaya Y, Miura M, Boyden PA, Stuyvers BD, Landesberg A.
  • Journal Title: Ann N Y Acad Sci. 1123 Pages: 79-95
  • Peer Reviewed
• [Presentation] Non-uniformity of Muscle Contraction Modulates Propagation Features of Ca^<2+> Waves in Rat Cardiac Muscle. (2011)
  • Author(s): Naomi Murai, Masahito Miura, Taiki Hattori, Chiyohiko Shindoh
  • Organizer: 第75回日本循環器学会
  • Place of Presentation: 横浜
  • Year and Date: 2011-03-20
• [Presentation] Regional Increase in Extracellular Potassium Can Be Arrhythmogenic by Non-uniform Muscle Contraction in Rat Cardiac Muscle. (2010)
  • Author(s): Taiki Hattori, Masahito Miura, Naomi Murai, Chiyohiko Shindoh
  • Organizer: 83^<th> AHA meeting
  • Place of Presentation: Chicago
  • Year and Date: 2010-11-17
• [Presentation] Non-uniform Muscle Contraction Sustains and Facilitates Triggered Arrhythmias in Rat Cardiac Muscle. (2009)
  • Author(s): Taichi Nishio, Masahito Miura, Taiki Hattori, Naomi Murai, Chiyohiko Shindoh
  • Organizer: 82^<th> AHA meeting
  • Place of Presentation: Orlando
  • Year and Date: 2009-11-18
• [Presentation] ラット心室筋における不均一収縮が持続性頻拍の頻拍間隔に与える影響 (2009)
  • Author(s): 西尾太一、三浦昌人、進藤千代彦
  • Organizer: 第24回日本不整脈学会学術大会
  • Place of Presentation: 京都
  • Year and Date: 2009-07-02
• [Presentation] Maintenance of Triggered Arrhythmias by Non-uniform Excitation-Contraction Coupling in Rat Cardiac Muscle. (2008)
  • Author(s): Masahito Miura, Taichi Nishio, Chiyohiko Shindoh, Hiroaki Shimokawa.
  • Organizer: 81^<th> AHA meeting
  • Place of Presentation: New Orleans
  • Year and Date: 2008-11-11
• [Remarks] ホームページ等