• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to previous page

An electrophysiological study on miniature Ca relelase from the sarcoplasmic reticulum in cardiac myocytes.

Research Project

Project/Area Number 63570040
Research Category

Grant-in-Aid for General Scientific Research (C)

Allocation TypeSingle-year Grants
Research Field General physiology
Research InstitutionSaga Medical School (1989)
Kyushu University (1988)

Principal Investigator

EHARA Tsuguhisa  Saga Medical School, Dept. of Physiology Professor, 医学部, 教授 (50037446)

Co-Investigator(Kenkyū-buntansha) ONO Kyoichi  Kyushu Univ., Faculty of Medicine Dept. of Physiology, Assistant, 医学部, 助手 (70185635)
Project Period (FY) 1988 – 1989
Project Status Completed (Fiscal Year 1989)
Budget Amount *help
¥2,200,000 (Direct Cost: ¥2,200,000)
Fiscal Year 1989: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 1988: ¥1,300,000 (Direct Cost: ¥1,300,000)
KeywordsCa^<2+>-mediated ion channel / sarcoplasmic reticulum / whole cell recording / caffeine / Ca release / 心室筋細胞
Research Abstract

Abstract. In order to examine the effects of increased intracellular Ca^<2+> level on the membrane electrical activity, caffeine, the agent which facilitates Ca^<2+> release from the sarcoplasmic reticulum, was applied to single ventricular cells of the guinea-pig, under condition of the whole cell recording. Caffeine (10 - 25 mM) induced a burst of pulse-like small inward currents. The amplitude of the pulse-like inward currents, which appeared to have a unit magnitude, decreased as the membrane was depolarized, and the reversal potential was estimated to be near 0 mV. Thus, the responsible ion channel may have a unit conductance of 250 - 300 pS. The pulse-like activity persisted when external NaCl was replaced with LiCl, but it disappeared in Tris-Cl solution. Large depolarizations producing sustained cell shortening or intracellular Ca^<2+>-injection enhanced the pulse-like events, suggesting a role of intracellular Ca^<2+> in this phenomenon. Ni^<2+> ions partially inhibited the pulse-like activity. Thus, the ventricular cells appeared to have Ca^<2+>-mediated cation channels with a large conductance, but possible involvement of a specific action of caffeine in the channel activation was not excluded.

Report

(3 results)
  • 1989 Annual Research Report   Final Research Report Summary
  • 1988 Annual Research Report
  • Research Products

    (20 results)

All Other

All Publications (20 results)

  • [Publications] Ehara,T.: "Calcium-activated non-selective cation channel in single ventricular cells isolated from adult guinea-pig hearts." J.Physiol.403. 117-133 (1988)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1989 Final Research Report Summary
  • [Publications] Matsuoka,S.: "Reversal Potential of the Na-Ca exchange current in the cardiac myocyte of the guinea-Pig." Biomed.Res.Suppl.2. 149-152 (1989)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1989 Final Research Report Summary
  • [Publications] Ehara,T.: "Measurement of reversal potential of Na/Ca exchange current in single ventricular cells of guinea-pig." J.physiol. 410. 227-249 (1989)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1989 Final Research Report Summary
  • [Publications] Ehara,T.: "Chloride-sensitive nature of the adrenaline-induced currents in guinea-pig ventricular cells." J.Physiol.(1990)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1989 Final Research Report Summary
  • [Publications] Ehara,T.: "Anion channels activated by adrenaline in cardiac myocytes." Nature. (1990)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1989 Final Research Report Summary
  • [Publications] Noma,A.: "Isolated Adult Cardiac Myocytes.Vol.II(eds.by G.Isenberg and H.M.Piper)" CRC press,U.S.A., 117-125 (1989)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1989 Final Research Report Summary
  • [Publications] Ehara, T.: "Calcium-activated non-selective cation channel in single ventricular cells isolated from adult guinea-pig hearts." J. Physiol.403. 117-133 (1988)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1989 Final Research Report Summary
  • [Publications] Matsuoka, S.: "Reversal potential of the Na-Ca exchange current in the cardiac myocyte of the guinea-pig." Biomed. Res. Suppl., 2: 149-152, 1989.

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1989 Final Research Report Summary
  • [Publications] Ehara, T.: "Measurement of reversal potential of Na/Ca exchange current in single ventricular cells of guinea-pig." J. Physiol., 410: 227-249, 1989.

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1989 Final Research Report Summary
  • [Publications] Ehara, T.: "Choloride-sensitive nature of the adrenaline-induced currentsin guinea-pig ventricular cells." J. Physiol., 1990.

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1989 Final Research Report Summary
  • [Publications] Ehara, T.: "Anion channels activated by adrenalin in cardiac myocytes." Nature, 1990.

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1989 Final Research Report Summary
  • [Publications] Matsuoka,S.: "Reversal potential of the Na-Ca exchange current in the cardiac myocyte of the guinea-pig." Biomed.Res.Suppl.2. 149-152 (1989)

    • Related Report
      1989 Annual Research Report
  • [Publications] Ehara,T.: "Measurement of reversal potential of Na/Ca exchange current in single ventricular cells of guinea-pig." J.Physiol.410. 227-249 (1989)

    • Related Report
      1989 Annual Research Report
  • [Publications] Ehara,T.: "chloride-sensitive nature of the adrenaline-induced currents in guinea-pig ventricular cells." J.Physiol.(1990)

    • Related Report
      1989 Annual Research Report
  • [Publications] Ehara,T.: "Anion channels activated by adrenaline in cardiac myocytes." Nature. (1990)

    • Related Report
      1989 Annual Research Report
  • [Publications] Noma,A.: "Isolated Adult Cardiac Myocytes.Vol.II(eds.by G.Isenberg and H.M.Piper)" CRC press,U.S.A., 117-125 (1989)

    • Related Report
      1989 Annual Research Report
  • [Publications] Ehara, T.: J. Physiol.403. 117-133 (1988)

    • Related Report
      1988 Annual Research Report
  • [Publications] Matsuoka, S.: Biomed. Res.9.Suppl.149-152 (1988)

    • Related Report
      1988 Annual Research Report
  • [Publications] Ehara, T.: J. Physiol. (1989)

    • Related Report
      1988 Annual Research Report
  • [Publications] Ehara, T.: Amer. J. Physiol.

    • Related Report
      1988 Annual Research Report

URL: 

Published: 1988-04-01   Modified: 2016-04-21  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi