Shaking up glycolysis: Sustained, high lactate flux during aerobic rattling.
Shaking up glycolysis: Sustained, high lactate flux during aerobic rattling.
复制标题
摇动糖酵解：有氧运动期间持续的高乳酸通量。
DOI：
10.1073/pnas.98.2.723
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发表时间：
2001
影响因子：
11.1
通讯作者：
Conley,KE
中科院分区：
文献类型：
--
作者：
Kemper,WF;Lindstedt,SL;Hartzler,LK;Hicks,JW;Conley,KE
糖酵解提供的大量ATP被认为是脊椎动物肌肉细胞缺氧的反映。另一种假设是，收缩过程中产生的乳酸反映了在充氧条件下持续的糖酵解ATP供应。我们通过比较缺氧期间的细胞内糖酵解和持续有氧收缩期间肌肉的乳酸外流来区分这些假说。我们检查了响尾蛇的尾部肌肉，因为它具有均匀的细胞特性，独特的血液循环，以及长时间保持嘎嘎作响的能力。在这里，我们表明糖酵解是独立于O2水平的，并提供持续尾部晃动所需的高ATP的三分之一。由于血液流速是脊椎动物肌肉中最高的，因此可以通过快速的H+和乳酸外流来避免疲劳。这些结果否定了糖酵解必然反映细胞缺氧的假设。相反，他们证明了糖酵解可以提供高和可持续的ATP供应以及氧化磷酸化，而不会导致肌肉疲劳。
Substantial ATP supply by glycolysis is thought to reflect cellular anoxia in vertebrate muscle. An alternative hypothesis is that the lactate generated during contraction reflects sustained glycolytic ATP supply under well-oxygenated conditions. We distinguished these hypotheses by comparing intracellular glycolysis during anoxia to lactate efflux from muscle during sustained, aerobic contractions. We examined the tailshaker muscle of the rattlesnake because of its uniform cell properties, exclusive blood circulation, and ability to sustain rattling for prolonged periods. Here we show that glycolysis is independent of the O2level and supplies one-third of the high ATP demands of sustained tailshaking. Fatigue is avoided by rapid H+and lactate efflux resulting from blood flow rates that are among the highest reported for vertebrate muscle. These results reject the hypothesis that glycolysis necessarily reflects cellular anoxia. Instead, they demonstrate that glycolysis can provide a high and sustainable supply of ATP along with oxidative phosphorylation without muscle fatigue.