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

A ^<31>P NMR Study on HIbernating Myocardium

Research Project

Project/Area Number 01480246
Research Category

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

Allocation TypeSingle-year Grants
Research Field Circulatory organs internal medicine
Research InstitutionShiga University of Medical Science

Principal Investigator

KINOSHITA Masahiko  Shiga University of Medical Science The First Department of Internal Medicine, Professor, 医学部, 教授 (60093168)

Co-Investigator(Kenkyū-buntansha) TSUTAMOTO Takayoshi  Shiga University of Medical Science The First Department of Internal Medicine, A, 医学部, 助手 (40197695)
TAKAHASHI Masayuki  Shiga University of Medical Science The First Department of Internal Medicine, A, 医学部, 助手 (40179528)
FUKUHARA Takehisa  Shiga University of Medical Science The First Department of Internal Medicine, A, 医学部, 講師 (90156802)
MITSUNAMI Kenichi  Shiga University of Medical Science The First Department of Internal Medicine, A, 医学部, 助教授 (10127037)
Project Period (FY) 1989 – 1991
Project Status Completed (Fiscal Year 1991)
Budget Amount *help
¥6,900,000 (Direct Cost: ¥6,900,000)
Fiscal Year 1991: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1990: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 1989: ¥5,700,000 (Direct Cost: ¥5,700,000)
KeywordsMyocardial hibernation / Rapid ventricular pacing / ^<31>P NMR spectroscopy / Conductance catheter method / High energy Phosphate / High energy Phosphate / Intracellular calcium
Research Abstract

The term "hibernating myocardium" refers to chronic ischemia in which the blood supply to the myocardium is not low enough to cause tissue necrosis, but is low enough to result in chronic regional left ventricular dysfunction. The mechanism of left ventricular dysfunction in the hibernating myocardium is unknown mainly due to lack of adequate experimental models for it. The mechanism of left ventricular dysfunction induced by chronic rapid ventricular pacing also has not as yet been fully elucidated, but some investigators assume that it results from relative myocardial ischemia. So we investigated the mechanism of pacing-induced left ventricular dysfunction employing in vivo ^<31>P NMR spectroscopy using a chronically implanted radio frequency coil on the pericardium over the left ventricle in the dog, and tried to make it clear whether pacing-induced left ventricular dysfunction is considered as an adequate model for hibernating myocardium.
The heart was rapidly paced using chronicall … More y implanted pacing leads on the right ventricle at a rate 250 to 270 beats per minute for 3 to 5 weeks. The left ventricular end-diastolic pressure was high at the end of rapid pacing and remained high for a week after the cessation of pacing. The left ventricular dp/dt was decreased at the end of rapid pacing but increased significantly 1 hour after the cessation of pacing. Serial ^<3l>P NMR spectroscopy revealed a tendency of reduction in myocardial contents of adenosine triphosphate (ATP) and phosphocreatine (PCr) after the rapid ventricular pacing compared with before, but the recovery in their contents after the cessation of pacing seemed to be minimum during the following 3 hours. We measured the myocardial contents of ATP, ADP, AMP, and PCr by high-performance liquid chromatography after the NMR study in some cases, but couldn't find a significant reduction compared with the myocardium in shamoperated dogs which had normal left ventricular end-diastolic pressure and dp/dt. But this seemed to be due to a small number of cases measured. These findings may suggest the participation of myocardial ischemia in the mechanism of left ventricular dysfunction induced by chronic rapid ventricular pacing. Tbus, pacing-induced left ventricular dysfunction may be an adequate model for hibernating myocardium, but further investigation is necessary before reaching the definite conclusion. Less

Report

(4 results)
  • 1991 Annual Research Report   Final Research Report Summary
  • 1990 Annual Research Report
  • 1989 Annual Research Report
  • Research Products

    (5 results)

All Other

All Publications (5 results)

  • [Publications] 河崎 春洋: "虚血・再潅流障害に対するNicovandilの効果ー ^<31>PMRS摘出心潅流標本を用いての検討" Therapeutic Research. Vol12.No4. (1991)

    • Related Report
      1990 Annual Research Report
  • [Publications] Kenji Hashimoto: "Coronary Effects of Nicorandil in Comparison with Nitroglycerin in Chronic Conscious Dogs" Cardiovascular Drugs and Therapy. 5. (1990)

    • Related Report
      1990 Annual Research Report
  • [Publications] Kenji Hashimoto: "Left Ventricular Effects of Nicorandil in Comparison with Nitroglycerin in Chronic Conscious Dogs" Cardiovascular Drugs and Therapy. 4. 1449-1454 (1990)

    • Related Report
      1990 Annual Research Report
  • [Publications] Masahiko Kinoshita: "Pharmacology and Therapeutic Effects of Nicorandil" Cardiovascular Drugs and Therapy. 4. 1075-1088 (1990)

    • Related Report
      1990 Annual Research Report
  • [Publications] Kenichi Mitsunami: " ^<31>P Nuclear Magnetic Resonance Spectroscopic Analysis of Human Hearts with Previous Myocardial Infarction" Japanese Circulation Journal.

    • Related Report
      1990 Annual Research Report

URL: 

Published: 1989-04-01   Modified: 2016-04-21  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi