心筋虚血再灌流傷害の発生におけるTRPCチャネルの役割の検討

2010 Fiscal Year Annual Research Report

• Project/Area Number: 22590205
• Research Institution: Shiga University of Medical Science
• Principal Investigator: 松浦 博 滋賀医科大学, 医学部, 教授 (60238962)
• Co-Investigator(Kenkyū-buntansha): 尾松 万里子 滋賀医科大学, 医学部, 准教授 (80161397) ; 小嶋 亜希子 滋賀医科大学, 医学部, 助教 (50447877) ; 林 維光 滋賀医科大学, 医学部, 助教 (80242973)
• Keywords: Ca^<2+>パラドックス / マウス心室筋細胞 / TRPCチャネル / 共焦点レーザ顕微鏡 / fluo-3 / 虚血再灌流傷害 / Ca^<2+>過負荷 / パッチクランプ法

Research Abstract

1.マウス心臓から酵素処理により単離した心室筋細胞に蛍光Ca^<2+>指示薬(fluo-3)を負荷し,共焦点レーザー顕微鏡を用いて細胞内Ca^<2+>濃度のイメージング解析を行った.マウス心室筋細胞を正常タイロード液(1.8mM,Ca^<2+>を含む)で灌流後に,無Ca^<2+>タイロード液(正常タイロード液からCa^<2+>を除去した)で10～20分間灌流して,さらに正常タイロード液で再灌流した.その結果,約60%の細胞において,急激な細胞内Ca<2+>濃度の上昇と細胞拘縮が発生した(Ca^<2+>パラドックス).このCa^<2+>パラドックスの発生は,TRPC(transient receptor potential canonical)チャネル阻害剤(2-aminoethoxydiphenyl borate,Gd^<3+>,La^<3+>,SKF-96365)や抗TRPC1抗体を投与すると,有意に減少した.
2.パッチクランプ法を用いて,マウス心室筋細胞に筋小胞体のCa^<2+> ATPaseの抑制剤であるタプシガルギンを投与すると,直線上の電流電圧関係を示し,2-aminoethoxydiphenyl borateでブロックされる電流が記録できたため,TRPCチャネル電流の存在が確認できた.
これらの実験結果から,心筋のCa^<2+>過負荷を原因とする心筋傷害であるCa^<2+>パラドックスに,Ca^<2+>透過性の細胞膜陽イオン輸送チャネルであるTRPCチャネルを介するCa^<2+>流入が関与しているということが明らかとなった.

Research Products

• [Journal Article] Lysophosphatidylcholine enhances I_<Ks> currents in cardiac myocytes through activation of G protein, PKC and Rho signaling pathways. (2011)
  • Author(s): Ding WG, Toyoda F, Ueyama H, Matsuura H
  • Journal Title: J Mol Cell Cardiol Volume: 50 Pages: 58-65
  • Peer Reviewed
• [Journal Article] Minor contribution of cytosolic Ca^<2+> transients to the pacemaker rhythm in guinea pig sinoatrial node cells. (2011)
  • Author(s): Himeno Y, Toyoda F, Satoh H, Amano A, Cha CY, Matsuura H, Noma A
  • Journal Title: Am J Physiol Volume: 300 Pages: H251-H261
  • Peer Reviewed
• [Journal Article] Reciprocal control of hERG stability by hsp70 and hsc70 with implication for restoration of LQT2 mutant stability. (2011)
  • Author(s): Li P, Ninomiya H, Kurata Y, Kato M, Miake J, Yamamoto Y, Igawa O, Nakai, A, Higaki K, Toyoda F, Wu J, Horie M, Matsuura H, Yoshida A, Shirayoshi Y, Hiraoka M, Hisatome I
  • Journal Title: Circ Res Volume: 108 Pages: 458-468
  • Peer Reviewed
• [Journal Article] Self-beating atypically shaped cardiomyocytes survive a long-term postnatal development preserving expression of fetal cardiac genes in mice. (2010)
  • Author(s): Omatsu-Kanbe M, Yamamoto T, Mori Y, Matsuura H
  • Journal Title: J Histochem Cytochem Volume: 58 Pages: 543-551
  • Peer Reviewed
• [Journal Article] KCNE2 modulation of Kv4.3 current and its potential role in fatal rhythm disorders. (2010)
  • Author(s): Wu J, Shimizu W, Ding W-G, Ohno S, Toyoda F, Itoh H, Zang W-J, Miyamoto Y, Kamakura S, Matsuura H, Nademanee K, Brugada J, Brugada P, Brugada R, Vatta M, Towbin JA, Antzelevitch C, Horie M
  • Journal Title: Heart Rhythm Volume: 7 Pages: 199-205
  • Peer Reviewed
• [Journal Article] Characterization of the rapidly activating delayed rectifier potassium current, 1_<Kr>, in HL-1 mouse atrial myocytes. (2010)
  • Author(s): Toyoda F, Ding WG, Zankov DP, Omatsu-Kanbe M, Isono T, Horie M, Matsuura H
  • Journal Title: J Membr Biol Volume: 235 Pages: 73-87
  • Peer Reviewed
• [Journal Article] Ca^<2+> paradox injury mediated through TRPC channels in mouse ventricular myocytes. (2010)
  • Author(s): Kojima A, Kitagawa H, Omatsu-Kanbe M, Matsuura H, Nosaka S
  • Journal Title: Br J Pharmacol Volume: 161 Pages: 1734-1750
  • Peer Reviewed
• [Journal Article] Presence and functional role of the rapidly activating delayed rectifier K^+ current in left and right atria of adult mice. (2010)
  • Author(s): Nakamura H, Ding WG, Sanada M, Maeda K, Kawai H, Maegawa H, Matsuura H
  • Journal Title: Eur J Pharmacol Volume: 649 Pages: 14-22
  • Peer Reviewed
• [Journal Article] Atrioventricular block-induced Torsades de Pointes with clinical and molecular backgrounds similar to congenital long QT syndrome. (2010)
  • Author(s): Oka Y, Itoh H, Ding WG, Shimizu W, Makiyama T, Ohno S, Nishio Y, Sakaguchi T, Miyamoto A, Kawamura M, Matsuura H, Horie M
  • Journal Title: Circ J Volume: 74 Pages: 2562-2571
  • Peer Reviewed
• [Presentation] Sevoflurane protects cardiomyocyte from Ca^<2+> paradox by preserving SR Ca 2+ and blocking TRPC channel. (2010)
  • Author(s): Kojima A, Kitagawa H, Omatsu-Kanbe M, Matsuura H, Nosaka S
  • Organizer: American Society of Anesthesiologists 2010 Annual Meeting
  • Place of Presentation: San Diego, CA, USA
  • Year and Date: 2010-10-16
• [Presentation] Presence and properties of atypically-shaped cardiomyocytes derived from ventricular tissue of mouse heart. (2010)
  • Author(s): Matsuura H, Omatsu-Kanbe M
  • Organizer: J Physiol Sci 60:S18
  • Place of Presentation: いわて県民情報交流センター(岩手県)
  • Year and Date: 2010-05-19
• [Presentation] Self-beating atypically-shaped cardiomyocytes (ACMs) survive a long-term post-natal development while preserving the expression of fetal cardiac gene in mice. (2010)
  • Author(s): Omatsu-Kanbe M, Matsuura H
  • Organizer: J Physiol Sci 60:S269
  • Place of Presentation: いわて県民情報交流センター(岩手県)
  • Year and Date: 2010-05-19
• [Presentation] Postnatal developmental changes in the TRPC channels in mouse heart. (2010)
  • Author(s): Hoshino S, Matsuura H, Omatsu-Kanbe M
  • Organizer: J Physiol Sci 60:S119
  • Place of Presentation: いわて県民情報交流センター(岩手県)
  • Year and Date: 2010-05-19