Changes of myocardial high-energy phosphates with the cardiac cycle during acute or chronic myocardial stress
Changes of myocardial high-energy phosphates with the cardiac cycle during acute or chronic myocardial stress
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DOI：
10.1002/mrm.1910400513
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发表时间：
1998-11-01
影响因子：
3.3
通讯作者：
Neubauer, S
中科院分区：
文献类型：
--
作者：
Illing, B;Horn, M;Neubauer, S
心脏高能磷酸盐浓度是否在心动周期内发生变化仍存在争议，假设这种周期性变化在急性或慢性心肌应激期间加剧，在四种条件下灌流离体鼠心脏：(1)对照，(2)通过加倍灌流液[Ca~(2+)]进行变力刺激，(3)急性缺氧(缓冲液PO2类似于150托)，(4)衰竭、慢性梗死心脏，在心动周期的7个时间点获得P-31-MR频谱，在对照条件下，ATP(11+/-3%*，*P<；在高钙灌流条件下，磷酸肌酸(9+/-5%*)的循环不明显，ATP和无机磷的循环未达到显著水平；急性缺氧时，出现了ATP(10+/-4%*)和无机磷(11+/-4%*)的循环，而磷酸肌酸的循环变化不明显。在慢性梗死大鼠心脏中，ATP、磷酸肌酸和无机磷的周期性变化的程度并不明显，因此，在灌流的大鼠心脏中，可以检测到高能磷酸盐在心动周期中的微小振荡，但在急性或慢性应激中这种变化不会加剧。心脏周期内高能磷酸盐的浓度受到严格控制。
Whether changes of cardiac high-energy phosphate concentrations occur over the cardiac cycle remains controversial, The hypothesis was that such cyclical changes are accentuated during acute or chronic myocardial stress, Isolated rat hearts were perfused under four conditions: (1) control, (2) inotropic stimulation by doubling of perfusate [Ca2+], (3) acute hypoxia (buffer PO2 similar to 150 torr), and (4) failing, chronically infarcted hearts, P-31-MR spectra were obtained at seven time points of the cardiac cycle, Under control conditions, cyclical changes ("cycling") of ATP (11 +/- 3%*, *P < 0.05) and phosphocreatine (9 +/- 2%*) were detected, inorganic phosphate cycling did not reach statistical significance, At high [Ca2+] perfusion, cycling of phosphocreatine (9 +/- 5%*) was not accentuated, cycling of ATP and inorganic phosphate did not reach significance, During acute hypoxia, cycling of ATP (10 +/- 4%*) and inorganic phosphate (11 +/- 4%*) occurred, but cyclical changes of phosphocreatine were not significant. In chronically infarcted hearts, the extent of cyclical changes of ATP, phosphocreatine, and inorganic phosphate was not accentuated, Thus, in perfused rat heart, small oscillations of high-energy phosphates during the cardiac cycle are detectable, but such changes are not accentuated during acute or chronic stress. The concentrations of high-energy phosphates over the cardiac cycle are tightly regulated.