@article{oai:sapmed.repo.nii.ac.jp:00015464,
 author = {高橋, 延昭 and 高橋, 正樹},
 issue = {6},
 journal = {札幌医学雑誌 = The Sapporo medical journal, The Sapporo medical journal},
 month = {Dec},
 note = {The effect of alternating external calcium concentrations on potassium-induced contracture, with special reference to mechanical activation and inactivation curves, was examined using single muscle fibers taken from the walking leg muscles of crayfish （Cambarus clarkii） and the following results were obtained. 1） Although two methods used for the measurement of inactivation are already known in frog twitch fibers （cf. Hodgkin and Horowicz 1960, Frankenhaeuser and L?nnergren 1967）, a considerable difference between these two methods regarding the degree of inactivation for a given time in this preparation may be seen. 2） Inactivation, which depends on the conditioning of potassium concentration, first attains a stable value of inactivation with the conditioning time, and then slowly rises to level of full inactivation. 3） Under a condition of low calcium concentration （5mM）, activation and inactivation curves are shifted to lower potassium concentrations. The extent or degree of the shift of the inactivation curve is larger than that of the activation. 4） An increase of the calcium concentration （36.5mM） shifts both courves to higher potassium concentrations. The extent of the shift of both curves is approximately similar. 5） The time course of K-contracture （200mM K+） is affected by alternating calcium concentration as follows. In low calcium concentrations （5mM）, the ascending rate of the tension increased and the time course is shortened. On the other hand, in higher concentrations （36.5mM）, the former is decreased and the latter is prolonged. 6） The peak tension of K-contracture （200mM K+） increases with the increase of calcium concentration from 1 to 5mM. In higher calcium concentrations over 36.5mM the peak tension decreases although the concentration range from 5 to 36.5 mM gives maximal tension. 7） The size of area of 200mM-K contracture increases with the increase of calcium concentration from 1 to 13.5mM. Under the calcium concentration from 13.5mM up to 36.5mM, a stable value is maintained. However, higher calcium concentrations over 36.5 mM leads to a sudden increase of size of the area. On the basis of these results, the phasic nature in potassium-induced contracture of crayfish muscle fibers was discussed in comparison with that of frog twitch fibers.},
 pages = {571--581},
 title = {ザリガニ単一骨格筋線維のK拘縮に対する外液Ca++濃度の影響 : 特にmechanical activationならびにinactivationに関して},
 volume = {47},
 year = {1978}
}