| Project/Area Number |
12680012
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
体育学
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| Research Institution | Department of Sports Medicine, Institute of Health and Sport Sciences, University of Tsukuba, Tsukuba, Japan |
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Principal Investigator |
IRUKAYAMA-TOMOBE Yoko Department of Sports Medicine, Institute of Health and Sport Sciences, University of Tsukuba, RESEARCH ASSOCIATE, 体育科学系, 助手 (90312834)
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| Co-Investigator(Kenkyū-buntansha) |
MIYAUCHI Takashi Department of Internal Medicine, Institute of Clinical Sciences, University of Tsukuba, ASSISTANT PROFESSOR, 臨床医学系, 講師 (60222329)
MATSUDA Mitsuo Department of Sports Medicine, Institute of Health and Sport Sciences, University of Tsukuba, PROFESSOR, 体育科学系, 教授 (20110702)
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| Project Period (FY) |
2000 – 2001
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| Project Status |
Completed (Fiscal Year 2001)
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| Budget Amount *help |
¥3,400,000 (Direct Cost: ¥3,400,000)
Fiscal Year 2001: ¥1,300,000 (Direct Cost: ¥1,300,000)
Fiscal Year 2000: ¥2,100,000 (Direct Cost: ¥2,100,000)
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| Keywords | endothelin / endothelin receptor antagonist / redistribution of blood flow / microshere / treadmill / NOx / 慢性運動トレーニング / VO_2max |
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| Research Abstract |
Endothelin-1 (ET-1) is a vasoconstrictor peptide. Exercise results in redistribution of tissue blood flow, by which blood flow in increased in active muscles, whereas it is decreased in visceral circulation (such as in kidneys and spleen). We previously reported that an intense exercise causes the increase of ET-1 production in the internal organs, then, we hypothesized that ET-1 participates in the exercise-induced redistribution of tissue blood flow. We investigated the effects of acute ET_A receptor blockade on regional tissue blood flow during exercise in rats. Regional blood flow was measured using microsphere technique before and during treadmill running of 30 min duration under pretreatment with ET_A receptor antagonist (TA-0201) or vehicle (both n=7). The decreases in blood flows to the kidney and spleen induced by intense exercise under pretreatment with TA-0201 were significantly less compared with those under pretreatment with TA-0201 were significantly less compared with those under pretreatment with vehicle (kidney : 36.8 ± 7.1 vs. 66.9 ± 5.2 %. p<0.01, spleen : 31.6 ± 6.8 vs. 57.1 ± 9.2 %. p<0.05). Furthermore, the increases in blood flows to the active muscles induced by intense exercise under pretreatment with TA-0201 were significantly less compared with those under pretreatment with vehicle (tibialis anterior muscle : 223.7 ± 36.6 vs. 423.1 ± 83.0 %, p<0.05). The present study suggests that ET-1-mediated vasoconstriction participates in the decrease of blood flow in the kidneys and spleen of rats during exercise, thereby contributing to the increase of blood flow in the active muscles.
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