Temperature dependence of the inhibitory effects of orthovanadate on shortening velocity in fast skeletal muscle.
Temperature dependence of the inhibitory effects of orthovanadate on shortening velocity in fast skeletal muscle.
复制标题
原钒酸盐对快速骨骼肌缩短速度的抑制作用的温度依赖性。
DOI：
10.1016/s0006-3495(94)80947-6
复制
发表时间：
1994
影响因子：
3.4
通讯作者：
Cooke,R
中科院分区：
文献类型：
--
作者：
Pate,E;Wilson,GJ;Bhimani,M;Cooke,R
我们研究了正磷酸盐（P（i））类似物原钒酸盐（Vi）对活化的、化学剥皮的脊椎动物骨骼肌纤维的最大缩短速度（Vmax）的影响。使用新的“温度跳跃”协议，可以从高温下的活化纤维获得可重复的数据，并且我们已经检查了在5-30摄氏度的温度范围内增加[Vi]对Vmax的影响。我们发现，当温度≤ 20 ℃时，增加[Vi]会抑制Vmax;当温度≥ 25 ℃时，增加[Vi]不会抑制Vmax。与Vi结合的连接横桥被认为是弱结合肌动蛋白-肌球蛋白的类似物。ADP-P（i）状态。数据表明，弱束缚的Vi态可以在低温下抑制速度，但在高温下不会，并且在< 5摄氏度的狭窄温度范围内发生转变。这意味着一种高度合作的互动。数据还定义了在5-30 ℃温度范围内化学去皮兔腰肌纤维的Vmax的Q10为2.1。
We have investigated the effects of the orthophosphate (P(i)) analog orthovanadate (Vi) on maximum shortening velocity (Vmax) in activated, chemically skinned, vertebrate skeletal muscle fibers. Using new "temperature-jump" protocols, reproducible data can be obtained from activated fibers at high temperatures, and we have examined the effect of increased [Vi] on Vmax for temperatures in the range 5–30 degrees C. We find that for temperatures < or=20 degrees C, increasing [Vi] inhibits Vmax; for temperatures > or=25 degrees C, increasing [Vi] does not inhibit Vmax. Attached cross-bridges bound to Vi are thought to be an analog of the weakly bound actin-myosin.ADP-P(i) state. The data suggest that the weakly bound Vi state can inhibit velocity at low temperature, but not at high temperature, with the transition occurring over a narrow temperature range of < 5 degrees C. This suggests a highly cooperative interaction. The data also define a Q10 for Vmax of 2.1 for chemically skinned rabbit psoas fibers over the temperature range of 5–30 degrees C.