X-ray diffraction of actively shortening muscle.
X-ray diffraction of actively shortening muscle.
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主动缩短肌肉的 X 射线衍射。
DOI：
10.1073/pnas.73.3.813
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发表时间：
1976
影响因子：
11.1
通讯作者：
R W Lymn
中科院分区：
文献类型：
--
作者：
R. J. Podolsky;H. St Onge;L. Yu;R W Lymn
通过位置敏感探测器从静止和激活的青蛙缝匠肌获得低角x射线衍射图。虽然强度比I10/I11降低了许多倍激活后，它几乎是相同的等长和等张收缩。因此，运动对低阶赤道型的影响比从静止到活动的转变小得多。对10和11反射的分析分别表明，I10和I11在激活时变化很小，并且在从等长收缩到等张收缩的过渡中它们都增加了少量。如果强度比可以作为衡量横桥数，结果提供的证据表明，在一个积极缩短肌肉的力下降主要是由于运动的影响的配置，而不是数量，横桥。
Low angle x-ray diffraction patterns were obtained from resting and activated frog sartorius muscles by means of a position-sensitive detector. Although the intensity ratio I10/I11 decreased many-fold upon activation, it was nearly the same during isometric and isotonic contraction. Thus, motion has a much smaller effect on the low order equatorial pattern than the transition from rest to activity. Analysis of the 10 and 11 reflections separately showed that I10 and I11 change reciprocally upon activation, and that they both increase by a small amount in the transition from isometric to isotonic contraction. If the intensity ratio can be taken as a measure of cross-bridge number, the results provide evidence that the drop in force in an actively shortening muscle is due primarily to the influence of motion on the configuration, rather than the number, of cross-bridges.