Atrial fibrillation and uncoupling : Changing of gap junction by aging produces the abnormal impulse propagation and associated arrhythmias.

2008 Fiscal Year Final Research Report

• Project/Area Number: 19790546
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Single-year Grants
• Research Field: Circulatory organs internal medicine
• Research Institution: Hyogo College of Medicine
• Principal Investigator: MASUMIYA Haruko Hyogo College of Medicine, 医学部, 助教 (30286744)
• Project Period (FY): 2007 – 2008
• Keywords: 循環器 / 心房細動 / コネキシン / 自動能 / 洞房結節

Research Abstract

申請者は心房細動をはじめとする異所性自動能の潜在的な発生メカニズムを解明し、従来のような不整脈が発生した場合のdown-stream治療法に代わる、病態の本質を治療の対象とするup-stream治療法の確立を目的としている。本研究はその全体プロジェクトの中で心房細動とコネキシン(gap junction)に焦点を絞り、agingに伴った正常および異所性自動能発生とその伝播過程でのコネキシンの生理的役割の解明を目指した。
本研究期間においては最初に正常なリズムに関する検討を行った。洞房結節標本の光学的膜電位計測法による実験系とその解析法をウサギ摘出洞房結節標本にて確立し、自動拍動の発生には個々の洞房結節細胞の性質とgap junction を介した細胞間の相互作用が寄与していること、またこれまでに報告されている以上に洞房結節領域内は電気生理学的に複雑であることを明らかにした。
現在はagingが及ぼす自動拍動の発生とその興奮伝播に対する影響を若年と老年ラットの洞房結節を標本として、膜電位イメージング法にて比較・検討中である。

Research Products

• [Journal Article] Inhomogeneous distribution of action potential characteristics in the rabbit sino-atrial node revealed by voltage imaging (2009)
  • Author(s): Masumiya H, Oku Y, Okada Y.
  • Journal Title: J. Physiol. Sci. May 59(3) Pages: 227-241
  • Peer Reviewed
• [Journal Article] Mitsugumin 53- mediated maintenance of K+ currents in cardiac myocytes (2009)
  • Author(s): Masumiya H, Asaumi Y, Nishi M, Minamisawa S, Adachi-Akahane S, Yoshida M, Kangawa K, Ito K, Kagaya Y, Yanagisawa T, Yamazaki T, Ma J, Takeshima H.
  • Journal Title: Channels. Jan-Feb 3(1) Pages: 6-11
  • Peer Reviewed
• [Journal Article] MG53 nucleates assembly of cell membrane repair machinery (2009)
  • Author(s): Cai C, Masumiya H, Weisleder N, Matsuda N, Nishi M, Hwang M, Ko JK, Lin P, Thornton A, Zhao X, Pan Z, Komazaki S, Brotto M, Takeshima H, Ma J
  • Journal Title: Nature Cell Biology. Jan 11(1) Pages: 56-64
  • Peer Reviewed
• [Journal Article] MG53 regulates membrane budding and exocytosis in muscle cells (2009)
  • Author(s): Cai C, Masumiya H, Weisleder N, Pan Z, Nishi M, Ko J-K, Komazaki S, Takeshima H, Ma J
  • Journal Title: J. Biol. Chem. Jan 30 284(5) Pages: 3314-3322
  • Peer Reviewed
• [Journal Article] Spatiotemporal organization of frog respiratory neurons visualized on the ventral medullary surface (2008)
  • Author(s): Oku Y, Kimura N, Masumiya H, Okada Y.
  • Journal Title: Respir Physiol Neurobiol 161 Pages: 281-290
  • Peer Reviewed
• [Journal Article] Potentiation of potassium currents by beta-adrenoceptor agonists in human urinary bladder smooth muscle cells: a possible electrical mechanism of relaxation (2008)
  • Author(s): Takemoto J, Masumiya H, Nunoki K, Sato T, Nakagawa H, Ikeda Y, Arai Y, Yanagisawa T.
  • Journal Title: Pharmacology 81 Pages: 251-258
  • Peer Reviewed
• [Journal Article] Cholesterol depletion modulates basal L-type Ca2+ current and abolishes its -adrenergic enhancement in ventricular myocytes (2008)
  • Author(s): Tsujikawa H, Song Y, Watanabe M, Masumiya H, Gupote SA, Ochi R, Okada T
  • Journal Title: Am J Physiol Heart Circ Physiol 294(1) Pages: H285-92
  • Peer Reviewed
• [Journal Article] Chemosensitive neuronal network organization in the ventral medulla analyzed by dynamic voltage-imaging (2007)
  • Author(s): Okada Y, Kuwana S, Masumiya H, Kimura N, Chen Z, Oku Y
  • Journal Title: Adv Exp Biol Med 605 Pages: 353-358
  • Peer Reviewed
• [Journal Article] Respiratory and metabolic acidosis differentially affect the respiratory neuronal network in the ventral medulla of neonatal rats (2007)
  • Author(s): Okada Y, Tamura Y, Masumiya H, Oku Y.
  • Journal Title: Eur J Neurosci 26(10) Pages: 2834-2843
  • Peer Reviewed
• [Journal Article] Postnatal developmental changes in activation profiles of the respiratory neuronal network in the rat ventral medulla (2007)
  • Author(s): Oku Y, Masumiya H, Okada Y.
  • Journal Title: J Physiol 585 Pages: 175-186
  • Peer Reviewed
• [Presentation] ウサギ洞房結節領域における興奮伝播の膜電位イメージング解析 (2008)
  • Author(s): 増宮晴子,岡田泰昌,越久仁敬
  • Organizer: 第85回日本生理学会大会
  • Place of Presentation: 東京
  • Year and Date: 20080325-27
• [Presentation] Homology of respiratory neuronal networks between frogs and rats: The brain adapts itself to the mode of ventilation (2007)
  • Author(s): Oku Y, Masumiya H, and Okada Y.
  • Organizer: 5th Congress of the International Society for Autonomic Neuroscience (ISAN)
  • Place of Presentation: 京都テルサ、Kyoto
  • Year and Date: 20071005-08
• [Presentation] Differential effects of respiratory and metabolic acidosis on the respiratory neuron network analyzed by voltage-imaging. (2007)
  • Author(s): Okada Y, Masumiya H, and Oku Y.
  • Organizer: 5th Congress of the International Society for Autonomic Neuroscience (ISAN),
  • Place of Presentation: 京都テルサ、Kyoto
  • Year and Date: 20071005-08
• [Presentation] カエル脳幹部呼吸神経活動の可視化 (2007)
  • Author(s): 越久仁敬,木村直史,増宮晴子,岡田泰昌
  • Organizer: 第30回日本神経科学大会
  • Place of Presentation: 横浜
  • Year and Date: 20070910-12
• [Presentation] Dynamic voltage-imaging analysis of the effects of acidosis on the respiratory neuronal network in the rat ventral medulla (2007)
  • Author(s): Okada Y, Masumiya H, and Oku Y
  • Organizer: 第47回日本呼吸器学会学術講演会 (English Session)
  • Place of Presentation: Toyko
  • Year and Date: 20070510-12