Project/Area Number |
08670772
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Circulatory organs internal medicine
|
Research Institution | Tokyo Medical and Dental University |
Principal Investigator |
KOIKE Akira Tokyo Medical and Dental University, Department of Medicine, Assistant professor, 医学部, 助手 (60234655)
|
Project Period (FY) |
1996 – 1997
|
Project Status |
Completed (Fiscal Year 1997)
|
Budget Amount *help |
¥2,200,000 (Direct Cost: ¥2,200,000)
Fiscal Year 1997: ¥1,200,000 (Direct Cost: ¥1,200,000)
Fiscal Year 1996: ¥1,000,000 (Direct Cost: ¥1,000,000)
|
Keywords | Heart failure / Exercise test / Ventilation / Potassium |
Research Abstract |
It has been suggested that the serum potassium concentration plays an important role in determining the increased ventilation during exercise. The present study was conducted to investigate the mechanisms of the increased ventilation during exercise, focusing the role of serum potassium in the ventilatory response to exercise, in patients with chronic heart failure. Thirteen patients performed 6 minutes of moderate-intensity constant work-rate exercise before and after oral administration of slow-release potassium chloride for 4 weeks. In 8 patients, serum potassium concentration was increased by more than 10 % after administration of potassium chloride. In these patients, serum potassium concentration was significantly increased from 3.58(]SY.+-。[)0.33 to 4.23(]SY.+-。[)0.29 mEq/l at rest and from 3.83(]SY.+-。[)0.43 to 4.70(]SY.+-。[)0.36 mEq/l at the end of exercise. However, minute ventilation at rest was 12.0(]SY.+-。[)2.6 L/min before and 12.3(]SY.+-。[)1.8 L/min after administration of potassium, showing no significant difference. Minute ventilation at the end of exercise was 43.5(]SY.+-。[)8.1 L/min after administration of potassium and did not differ from that before administration (44.5(]SY.+-。[)9.5 L/min). From the present study, it was strongly suggested that the serum potassium concentration is not an important factor in determining ventilatory response during exercise in patients with chronic heart failure.
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