| Project/Area Number |
61440042
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| Research Category |
Grant-in-Aid for General Scientific Research (A)
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| Allocation Type | Single-year Grants |
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| Research Field |
Circulatory organs internal medicine
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| Research Institution | KYUSHU UNIVERSITY |
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Principal Investigator |
NAKAMURA Motoomi Kyushu University, Faculty of Medicine, Professor, 医学部, 教授 (60037322)
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| Co-Investigator(Kenkyū-buntansha) |
TOMOIKE Hitonobu Kyushu University, Faculty of Medicine, Lecturer, 医学部, 講 (90112333)
AKAIKE Norio Kyushu University, Faculty of Medicine, Assistant professor, 医学部, 助教授 (30040182)
SUEISHI Katuo Kyushu University, Faculty of Medicine, Professor, 医学部, 教授 (70108710)
TAKESHITA Akira Kyushu University, Faculty of medicine, Assistant professor, 医学部, 助教授 (30038814)
KANAIDE Hideo Kyushu University, Faculty of medicine, Lecturer, 医学部, 講師 (80038851)
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| Project Period (FY) |
1986 – 1987
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| Project Status |
Completed (Fiscal Year 1987)
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| Budget Amount *help |
¥28,000,000 (Direct Cost: ¥28,000,000)
Fiscal Year 1987: ¥10,000,000 (Direct Cost: ¥10,000,000)
Fiscal Year 1986: ¥18,000,000 (Direct Cost: ¥18,000,000)
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| Keywords | coronaryarteryspasm / atherosclerosis / histamine / endothelium / caffeine / vascular smooth muscle / カフェイン / 動脈硬化 / 血管内皮細胞 / セロトニン |
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| Research Abstract |
1. Mechanisms of Coronary Arterial Spasm in Experimental Animal Model Endothelial balloon denudation of the coronary artery was performed under fluoroscopy in miniature pigs and the animals were fed laboratory chow for 3 months, after which coronary artery spasm was repeatedly provoked by histamine given intracoronarily. To evaluate coronary artery spasm without the influence of blood constituents and neural control and to quantitate the pharmacophysiological characteristics of histamine-induced coronary hyperconstriction, the same heart was isolated and perfused with Krebs-Henseleit solution under a constant perfusion pressure of 90 mmHg. Focally potentiated constriction of the coronary artery to histamine was reproducible in isolated pig hearts perfused with electrolyte solution containing 2.6 mM Ca^<2+>. The constriction of the denuded areas in response to histamine was topologically the same in vivo and in vitro. Alterations in the influx of Ca^<2+> in the presence of H_1-receptor stiumulation in vascular smooth muscle of the vessel with intimal thickening was suggested as a plausible mechanism of coronary spasm.
2. Cellular Mechanisms of Ca^<2+> Handling in Cultured Smooth muscle Cell Changes in the concentration of cytosolic free calcium were recorded microfluorometrically in rat vascular smooth muscle cells in primary culture and loaded with quin-2. Transient elevations of calcium repeatedly appeared in response to both repetitive depolarization (100 mM K^+) and caffeine (19 mM) applications with progressive reductions in peak levels. Quantitative analysis of released calcium suggested that caffeine- and depolarization-sensitive intracellular calcium strage sites is identical.
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