Gordon E E, Kira Y, Morgan H E
Adv Myocardiol. 1985;5:145-56. doi: 10.1007/978-1-4757-1287-2_11.
Increased aortic pressure accelerated protein synthesis in control-beating and arrested-drained hearts supplied with either glucose or pyruvate. Elevation of perfusion pressure from 60 to 120 mm Hg increased oxygen consumption in control-beating but not in arrested-drained preparations. Energy availability, as assessed by adenylate energy charge or creatine phosphate/creatine ratio, or both, was increased in arrested-drained hearts supplied with glucose and perfused at 60 and 120 mm Hg aortic pressure. In control-beating or arrested-drained hearts supplied with pyruvate, energy availability was not improved by elevation of aortic pressure from 60 to 120 mm Hg. An increase of perfusate calcium concentration from 0.5 to 5.0 mM in control-beating Langendorff preparations supplied with glucose and perfused at an aortic pressure of 90 mm Hg doubled oxygen consumption and decreased energy availability, but had no effect on the rate of protein synthesis. In arrested-drained hearts supplied with either glucose or pyruvate and calcium concentrations ranging from 0.5 to 5.0 mM, the rates at 120 mm Hg aortic pressure were 11-25% higher than at 60 mm Hg. These findings provide no evidence to implicate increased oxidative metabolism, energy availability, or extracellular calcium concentration as important factors in the mechanism that accounts for the effects of increased aortic pressure on protein synthesis.
在灌注葡萄糖或丙酮酸的正常搏动及停搏-引流心脏中，主动脉压力升高加速了蛋白质合成。将灌注压力从60 mmHg升高至120 mmHg，可使正常搏动心脏的耗氧量增加，但对停搏-引流心脏制剂则无此作用。在灌注葡萄糖且主动脉压力维持在60 mmHg和120 mmHg的停搏-引流心脏中，以腺苷酸能量负荷或磷酸肌酸/肌酸比值或两者评估的能量供应增加。在灌注丙酮酸的正常搏动或停搏-引流心脏中，将主动脉压力从60 mmHg升高至120 mmHg并不能改善能量供应。在灌注葡萄糖且主动脉压力为90 mmHg的正常搏动Langendorff制剂中，将灌注液钙浓度从0.5 mM增加至5.0 mM可使耗氧量加倍并降低能量供应，但对蛋白质合成速率无影响。在灌注葡萄糖或丙酮酸且钙浓度范围为0.5 mM至5.0 mM的停搏-引流心脏中，主动脉压力为120 mmHg时的速率比60 mmHg时高11%-25%。这些发现没有提供证据表明氧化代谢增加、能量供应或细胞外钙浓度升高是主动脉压力升高对蛋白质合成产生影响的机制中的重要因素。
