An analysis of the initial process of skeletal muscle contraction using the optical rotation signal.
| Project/Area Number |
06670069
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
General physiology
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| Research Institution | Waseda University |
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Principal Investigator |
WATANABE Akira Waseda University, School of Human Sciences, Department of Basic Human Sciences, Professor, 人間科学部, 教授 (30013791)
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| Project Period (FY) |
1994 – 1995
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| Project Status |
Completed (Fiscal Year 1995)
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| Budget Amount *help |
¥1,700,000 (Direct Cost: ¥1,700,000)
Fiscal Year 1995: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1994: ¥1,200,000 (Direct Cost: ¥1,200,000)
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| Keywords | Muscle / E-C coupling / Contraction / Ryanodine / Nitrendipine / Pertussis Toxin / Optical rotation / 骨格筋 / 複屈折性 / 施光性 / ライアノジン / カフェイン / 旋光性 / 横紋筋 |
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| Research Abstract |
The optical rotation signal of a skeletal muscle cell associated with the twitch contraction was recorded from a single frog muscle fiber. For the external medium, 90-95% deuterium oxide Ringer solution was employed to reduce mechanical movement. Moreover, the fiber was lightly pushed to the bottom of the chamber with a cylindrical lens. After these procedures no movement was visible under the dissection microscope. The chamber was placed on the specimen stage of a high-speed polarimeter. The incident light was quasi-monochromatic with a central wavelength of 550nm. When the fiber was stimulated with an electric pulse, a transient increase in dextrorotation with a duration of about 22ms was observed. The polarity of the signal was constant among preparations and did not reverse when the direction of action potential conduction was reversed. Ryanodine reduced the amplitude of the signal to about one-half of the control. Nitrendipine conspicuously reduced the duration of the signal. Pertussis toxin eliminated the optical rotation signal without changing the shape and magnitude of the internally recorded action potential or the birefringence signal recorded separately. We conclude that the optical rotation signal originates from the change in conformation of macromolecules which are related to the process of excitation-contraction coupling.
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Report
(3 results)
Research Products
(6 results)
