Taylor P B, Hunt D A
Can J Appl Sport Sci. 1980 Dec;5(4):232-5.
Work induced myocardial glycogen repletion was studied in an isolated perfused heart preparation. After 15 min of low or high workload perfusion with substrate free buffer, glycogen was depleted by 29% (p < .05) and 61% (p < .001) respectively. During the resynthesis phase with 11 mM glucose as substrate, glycogen was increased by 23% (p < .05) and 44% (p < .01) for the moderately and severely depleted hearts. The rate of glycogen resynthesis was 2.4 fold greater in the more severely depleted hearts. Providing the substrate depleted myocardium with 5.5 mM, 11 mM or 22 mM glucose during the recovery period resulted in glycogen resynthesis of 9.01, 9.95 and 16.53 mg/hr/gm dry wt. When severely depleted hearts were provided with 11 mM glucose or a combination of 11 mM glucose and 5 mM sodium pyruvate, glycogen repletion was 9.95 and 16.50 mg/hr/gm dry wt. These experiments indicate that an isolated perfused heart can be used to study work induced glycogen repletion which is responsive to a change in the preceding workload, substrate concentration and the availability of an alternative carbon source.
在离体灌注心脏标本中研究了工作诱导的心肌糖原再填充情况。在用无底物缓冲液进行15分钟的低或高工作负荷灌注后，糖原分别减少了29%（p <.05）和61%（p <.001）。在以11 mM葡萄糖为底物的再合成阶段，中度和重度糖原耗竭的心脏中糖原分别增加了23%（p <.05）和44%（p <.01）。在糖原耗竭更严重的心脏中，糖原再合成速率高出2.4倍。在恢复期为底物耗竭的心肌提供5.5 mM、11 mM或22 mM葡萄糖，导致糖原再合成分别为9.01、9.95和16.53 mg/hr/gm干重。当为严重糖原耗竭的心脏提供11 mM葡萄糖或11 mM葡萄糖与5 mM丙酮酸钠的组合时，糖原再填充分别为9.95和16.50 mg/hr/gm干重。这些实验表明，离体灌注心脏可用于研究工作诱导的糖原再填充，其对先前工作负荷、底物浓度和替代碳源可用性的变化有反应。
