| Project/Area Number |
62480203
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| Research Category |
Grant-in-Aid for General Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
Respiratory organ internal medicine
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| Research Institution | Shinshu University School of Medicine |
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Principal Investigator |
HANDA Kenjiro (1988) Shinshu University School of Medicine, Associate Professor, 医学部, 助教授 (70020724)
草間 昌三 (1987) 信州大学, 医学部, 教授 (70020708)
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| Co-Investigator(Kenkyū-buntansha) |
SAKAI Akio Shinshu University School of Medicine, Associate Professor, 医学部付属心脈管研究施設, 助教授 (70020758)
UEDA Gou Shinshu University School of Medicine, Professor, 医学部付属心脈管研究施設, 教授 (10020702)
FUKUSHIMA Masao Shinshu University School of Medicine, Assistant, 医学部付属病院, 助手 (30173339)
KUBO Keishi Shinshu University School of Medicine, Assistant Professor, 医学部, 講師 (80143965)
KOBAYASHI Toshio Shinshu University School of Medicine, Assistant Professor, 医学部付属病院, 講師 (80020775)
半田 健次郎 信州大学, 医学部, 助教授 (70020724)
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| Project Period (FY) |
1987 – 1988
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| Project Status |
Completed (Fiscal Year 1988)
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| Budget Amount *help |
¥2,200,000 (Direct Cost: ¥2,200,000)
Fiscal Year 1988: ¥2,200,000 (Direct Cost: ¥2,200,000)
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| Keywords | Alveolar hypoxia / High altitude / Right ventricular hypertrophy / Hypoxic Pulmonary vasoconstriction / ピカ(ナキウサギ) |
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| Research Abstract |
1) Cardiac morphological features under chronic hypoxia Three groups of male Wistar strain rats of newborn, 3 weeksage and 8 weeks-age were used to test the adaptative ability of age-dependent variability. Rats were raised to 2,400m altitude and had been kept for 7 to 9 weeks. In well-adapted rats under chronic mild hypoxia, cardiac hypertrophy should be restricted and haematocrit moderately elevated. Right ventricular wall should not react excessively. Mitochondria were small but cristal density and percentage area, estimated from electron micrographs, were found to be high. And to determine whether the heart of young, spontaneously hypertensive rat(SHR) could respond to chronically high altitude exposure with myocardial growth, SHR were raise to a high altitude research station at altitude of 2400m, where they were kept for 80 days. Chronic high altitude exposure caused increase of both right and left ventricular weights in both and controls.
2) Physiological characteristics of Pika, as high altitude adapted animals
We found pika, ochontona,living at Qinghai-Tibetan plateau are having completely adapted signs, especially like small degree of right ventricular hypertrophy, lower pulmonary artery pressure, and low haematocrit values. And these characteristics may have been genetically transmitted to following generation.
3) Mechanism of hypoxic pulmonary vasoconstriction
We investigated the effects of angiotensin converting enzyme inhibitor (captoril), calcium channel blocker (nifedipin), and thromboxane synthetase inhibitor on hypoxic pulmonary vasoconstriction in conscious sheep. Both captoril and nifesipin are potent vasodilating drug, and hypoxic vascular tone is not modulated by cyclooxygenase products.
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