1998 Fiscal Year Final Research Report Summary
Study in calcium in muscle by intracellular organelles
Project/Area Number |
09044243
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Research Category |
Grant-in-Aid for international Scientific Research
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Allocation Type | Single-year Grants |
Section | Joint Research |
Research Field |
動物生理・代謝
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Research Institution | Okazaki National Research Institutes |
Principal Investigator |
TSUTSUI Izuo National Institute for physiological Sciences, Assistant professor, 生理学研究所, 助手 (80202183)
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Co-Investigator(Kenkyū-buntansha) |
BONE Quentin Marine Biological Association, Plymouth UK,Department head, 海洋生物研究所, 部長
INOUE Isao Institute for Enzyme Research, Tokushima University, Associate Professor, 分子酵素学研究センター, 助教授 (80001973)
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Project Period (FY) |
1997 – 1998
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Keywords | Doliolum / sarcoplasmic reticulum / T system / Na / Ca exchange / marine plankton / intracellular Ca |
Research Abstract |
We have investigated the role of the intracelluar organelles to the function of the muscle contractility and the relaxation mechanism. At least there are many organelles which control the contraction and relaxation in muscle cell such as sarcoplasmic reticulum (SR), transvers tubular structure (T system), Ca pump, Na/Ca exchange mechanism, Ca channel, ryanodine receptor, DHP receptor and so on. To testify the role of such organe lles, we focused on the animals lucking these organelles. The typical example is the marine plankton Doliolum, which lucking the T system and SR together, shows the essential necessity of extracellular Ca for its contraction and the Ca get in the muscle through voltage gated Ca channel is extruded only by the Na/Ca exchange mechanism not by Ca pumpinging system, suggesting that the SR is not essential for muscle contraction and cytoplasmic Ca sequestering. On the other hard, by frequent stimulation Doliolum stop its movement for a while, indicating once the cytoplasmic Ca exceeded thecertain level it took a long time to extrude and lower intacellular Ca. Thus SR could play a role of continuous lowering the cytop)lasmic Ca level and fine tuning of the intracellular Ca level, ON the other hand the animal with 'T and SR organelles the activity of Na/Ca exchange for lowering intracellular Ca level is limited, strongly suggesting the transition of Ca control mechanism by developing the T' and SR organelles.
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Research Products
(2 results)