Project/Area Number |
01480115
|
Research Category |
Grant-in-Aid for General Scientific Research (B)
|
Allocation Type | Single-year Grants |
Research Field |
General physiology
|
Research Institution | Osaka University |
Principal Investigator |
SHIGA Takeshi Osaka Univ., Med. Sci., Dept. Physiol., Prof., 医学部, 教授 (10028350)
|
Co-Investigator(Kenkyū-buntansha) |
WATANABE Manabu Osaka Univ., Med. Sci., Dept. Physiol., Assistant, 医学部, 助手 (30182950)
MAEDA Nobuji Ehime Univ., Med. Sci., Dept. Physiol., Prof., 医学部, 教授 (50036464)
IMAI Kiyohiro Osaka Univ., Med. Sci., Dept. Physiol., Assistant. Prof., 医学部, 助教授 (50028528)
|
Project Period (FY) |
1989 – 1990
|
Project Status |
Completed (Fiscal Year 1990)
|
Budget Amount *help |
¥5,500,000 (Direct Cost: ¥5,500,000)
Fiscal Year 1990: ¥1,200,000 (Direct Cost: ¥1,200,000)
Fiscal Year 1989: ¥4,300,000 (Direct Cost: ¥4,300,000)
|
Keywords | Erythrocytes, / Life span, / Aging, / 2.3-DPG, / ATP, / Energy metabolism, / Deformability, / Rheology |
Research Abstract |
The life span of human erythrocytes in blood stream depends mainly on the easiness of their filtrability through spleen and on the adhesivity, thus on the cellular deformability. The present studies concerns with the deformability of the in vivo-aged erythrocytes. 1. A novel sensitive method for detecting a subtle decrease in cellular deformability is developed, which measures the deformation response in oscillatory shear flow. The frequency response of the aged erythrocytes begins to decrease at ca. 2 Hz at 25 C, while that of young erythrocytes does not at above 3 Hz. The main cause is suggested to be due to the increased intracellular viscosity. 2. The decreased energy metabolism in aged erythrocytes has long been said to cause the decrease of the deformability through some change in the dynamics of cytoskeletal structure, without quantitative studies. The present experiments show that the decrease of adenylates, ATP and 2, 3-DPG found in the aged erythrocytes does not affect the cellular deformability. On contrary, the artificially increased 2, 3-DPG impairs the deformability perhaps due to the increased intracellular viscosity.
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