Grant-in-Aid for Co-operative Research (A)
|Allocation Type||Single-year Grants |
Neurophysiology and muscle physiology
|Research Institution||Medical College of Oita |
YAMADA Kazuhiro Medical College of Oita, Professor, 医学部, 教授 (20053027)
YANAGIDA Toshio Osaka University, Professor, 基礎工学部, 教授 (30089883)
OGAWA Yasuo Juntendo University, Professor, 医学部, 教授 (50103841)
TOMITA Tadao Nagoya University, Professor, 医学部, 教授 (50078763)
SUGI Haruo Teikyo University, Professor, 医学部, 教授 (20082076)
EBASHI Seturou National Institute for Physiological Sciences, Director, 所長 (10009863)
太和田 勝久 九州大学, 理学部, 助教授 (20029507)
松原 一郎 東北大学, 医学部, 助教授 (90010040)
|Project Period (FY)
1987 – 1988
Completed (Fiscal Year 1988)
|Budget Amount *help
¥10,900,000 (Direct Cost: ¥10,900,000)
Fiscal Year 1988: ¥5,200,000 (Direct Cost: ¥5,200,000)
Fiscal Year 1987: ¥5,700,000 (Direct Cost: ¥5,700,000)
|Keywords||Sliding force / ATP hydrolysis / Myofilaments / Myofibrils / Muscle fibres / Inorganic phosphate / アクチンフイラメント / 収縮 / ミオシン / フィラメント滑走 / 細胞膜剥離標本 / リンNMR / X線回折法|
1. Sliding force-ATP hydrolysis relationship in myofilaments and myofibrils.
Yanagida was able to determine the force developed by single actin filaments and also showed that the myosin heads can produce the same ATP-dependent force as intact muscle. He also finds that the sliding distance per molecule of ATP split is over 100 um. Umazume, Kodama and Tawada made the similar studies on myofilaments. Part of these studies also supports the above-mentioned results by Yanagida. Ogawa was able to modify the force-ATP hydrolysis relationship by using several drugs.
2. Force-ATP hydrolysis relationship in skinned and glycerinated muscle fibers.
Iino studied the effect of inorganic phosphate on force developed by skinned skeletal muscle fibers. The results showed that the underlying mechanism of the effect of inorganic phosphate on isometric force may be more complex than has been postulated. Yamada, Kometani and Sugi were able to initial stuides of the force-ATP hydrolysis relationship by applying the newly-developed method utilizing caged ATP and caged Ca.
3. Force-ATP hydrolysis relationship in living muscle fibers.
Yamada, Sugi and Tomita studied skeletal and smooth muscle contraction using ^<31>P nuclear magnetic resonance. Yamada found the post-contractile splitting of ATP, which may closely be related to the unexplained energy found in muscle. Sugi and Tomita were able to determine factors that regulate gylcolysis.
4. Activation of contraction in smooth muscles.
Ebashi studied the regulation of contraction in smooth muscles, he continually finds the regulatory mechanism on the thin filaments.
Sugita found an intracellular alkalization of muscle fibers using metabolic inhibitors, which may be closely related to the mechanism of impaired contraction in McArdle disease. He also made an important contribution to the mechanism of Duchenne muscular dystrophy myopathy.