Regulation of intracellular magnesium concentration

2008 Fiscal Year Final Research Report

• Project/Area Number: 18390066
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: General physiology
• Research Institution: Tokyo Medical University
• Principal Investigator: KONISHI Masato Tokyo Medical University, 医学部, 教授 (20138746)
• Co-Investigator(Kenkyū-buntansha): HIROSE Kenzo 名古屋大学, 医学部, 教授 (00292730) ; NAKAYAMA Shinsuke 名古屋大学, 医学部, 准教授 (30192230) ; WATANABE Masaru 東京医科大学, 医学部, 講師 (60191798) ; YOKOYAMA Michiko 東京医科大学, 医学部, 兼任講師 (20398762)
• Project Period (FY): 2006 – 2008
• Keywords: マグネシウム / 膜輸送 / 心筋 / ATP

Research Abstract

細胞内マグネシウム濃度を維持する重要な輸送機構であるNa/Mg交換輸送について、心筋を用いてシステマティックな実験および解析を行い、その機能の詳細を明らかにした。細胞内外のNa, K, Mg, Caイオン濃度を種々に変えて実験を行い、Mgくみ出し輸送のイオン選択性を調べたところ、Na/Mg交換輸送は、細胞外Na と細胞内Mgによってのみ活性化され、細胞内Naと細胞外Mgによってのみ抑制されることがわかった。またNa/Mg交換輸送には細胞内ATPの存在が必須であり、細胞内ATP濃度が約400μM以下になるとMgくみ出し輸送が抑制されることが明らかになった。

Research Products

• [Journal Article] Differential effects of an expected actin-tropomyosin binding region of heat shock protein 20 on the relaxation in skinned carotid artery and taenia cecum from guinea pig (2009)
  • Author(s): Hashimoto, R., Yumoto, M., Watanabe, M., Konishi, M., Haraoka, J. and Miki, T.
  • Journal Title: Journal of Smooth Muscle Research 45 Pages: 63-74
  • Peer Reviewed
• [Journal Article] Mechanisms of the inhibitory effects of a phenoxazine compound, 2-amino-4,4α-dihydro-4α-7-dimethyl-3 H-phenoxazine-3-one, on the contraction of the smooth muscle of the guinea pig taenia cecum (2007)
  • Author(s): Musha, S., Watanabe, M., Tomoda, A. and Konishi, M.
  • Journal Title: Journal of Smooth Muscle Research 43 Pages: 15-24
  • Peer Reviewed
• [Journal Article] Use of the Ca-shortening curve to estimate the myofilament responsiveness to Ca^<2+> in tetanized rat ventricular myocytes (2006)
  • Author(s): Kusakari, Y., Hongo, K., Kawai, M., Konishi, M. and Kurihara, S.
  • Journal Title: Journal of Physiological Sciences 56 Pages: 219-226
  • Peer Reviewed
• [Journal Article] Effects of intracellular and extracellular concentrations of Ca^<2+>, K^+ and Cl^-on the Na^+-dependent Mg^<2+> efflux in rat ventricular myocytes (2006)
  • Author(s): Tashiro, M., Tursun, P., and Konishi, M.
  • Journal Title: Biophysical Journal 91 Pages: 244-254
  • Peer Reviewed
• [Journal Article] Metabolic inhibition strongly inhibits Na^+-dependent Mg^<2+> efflux in rat ventricular myocytes
  • Author(s): Tashiro, M., Inoue, H. and Konishi, M.
  • Journal Title: Biophysical Journal (in press)
• [Presentation] Is ATP required for activities of the Na^+/Mg^<2+> exchange? (2009)
  • Author(s): Tashiro, M., Inoue, H. and Konishi, M.
  • Organizer: 53rd Annual Meeting of the Biophysical Society
  • Place of Presentation: Boston, Massachusetts, U.S.A.
  • Year and Date: 2009-03-04
• [Presentation] 心筋細胞内Mg^<2+>濃度制御 (2008)
  • Author(s): 小西真人, 田代倫子, 井上華
  • Organizer: 第28回日本マグネシウム学会総会シンポジウム"マグネシウムの輸送"
  • Place of Presentation: 広島
  • Year and Date: 2008-11-29
• [Presentation] Metabolic inhibition of cardiac myocytes causes a large increase in intracellular Mg^<2+> concentration by breakdown of ATP and inhibition of Mg^<2+> transport (2008)
  • Author(s): 田代倫子、小西真人
  • Organizer: 第31回心筋代謝研究会
  • Place of Presentation: 東京
  • Year and Date: 2008-07-13
• [Presentation] ラット心室筋細胞におけるナトリウム依存性マグネシウム汲み出し輸送に対する代謝阻害と細胞内Phの影響 (2008)
  • Author(s): 田代倫子、小西真人
  • Organizer: 第85回日本生理学会
  • Place of Presentation: 東京
  • Year and Date: 2008-03-27
• [Presentation] 心筋代謝阻害時のNa^+/Mg^<2+>交換輸送活性 (2007)
  • Author(s): 田代倫子、小西真人
  • Organizer: 第84回日本生理学会
  • Place of Presentation: 大阪
  • Year and Date: 2007-03-20
• [Presentation] Metabolic inhibition largely diminishes Na^+-Mg^<2+> exchange in rat ventricular myocytes (2007)
  • Author(s): Konishi, M. and Tashiro M.
  • Organizer: 51st Annual Meeting of the Biophysical Society
  • Place of Presentation: Baltimore, Maryland, U.S.A.
  • Year and Date: 2007-03-05
• [Presentation] Na^+/Mg^<2+> exchange as an active extrusion pathway of cellular mangesium (2006)
  • Author(s): Konishi, M., Tashiro, M. and Tursun, P.
  • Organizer: 11th International Magnesium Symposium
  • Place of Presentation: Mie, Japan
  • Year and Date: 2006-10-25
• [Presentation] Na^+-dependent Mg^<2+> efflux is largely inhibited in deenergized heart cells (2006)
  • Author(s): Tashiro, M., Watanabe, M. and Konishi, M.
  • Organizer: 11th International Magnesium Symposium
  • Place of Presentation: Mie, Japan
  • Year and Date: 2006-10-24
• [Presentation] Na^+/Mg^<2+> exchange in rat ventricular myocytes (2006)
  • Author(s): Konishi, M., Tashiro, M. and Tursun, P.
  • Organizer: 6th Congress of the Federation of Asian and Oceanian Physiological Societies
  • Place of Presentation: Seoul, Korea
  • Year and Date: 2006-10-17
• [Presentation] Intracellular magnesium concentration is maintained by sodium/magnesium exchange in cardiac myocytes (2006)
  • Author(s): Konishi, M., Tursun, P. and Tashiro, M.
  • Organizer: 2^<nd> world congress of International Academy of Cardiovascular Sciences
  • Place of Presentation: Hokkaido, Japan
  • Year and Date: 2006-07-14
• [Remarks]
  • URL: http://www.tokyo-med.ac.jp/physiol/Pub2.html
• [Remarks] 第27回日本マグネシウム学会総会市民公開シンポジウム「ミネラルと健康」オーガナイザー、2007年11月9日, 東京.
• [Remarks] 筋肉の構造と機能のシンポジウムオーガナイザー(3/24/2008)
• [Remarks] 第28回日本マグネシウム学会総会シンポジウム"マグネシウムの輸送"オーガナイザー