Kanaide H, Meno H, Nakamura M
Br J Exp Pathol. 1987 Jun;68(3):319-30.
Early changes in metabolic and physical properties were determined in rat hearts during calcium paradox. Calcium paradox was induced under constant perfusion pressure (60 mmHg) or constant coronary flow rate (9.8 ml/min). Within 30 s after calcium repletion, in either case, NADH increased, despite a decrease in ATP and increases in ADP and AMP. Surface spectrophotometry showed a deoxygenation of the myoglobin, thereby indicating myocardial oxygen depletion. These changes were predominant under conditions of constant pressure perfusion. In association with a rapid development of contracture, there were also a reduction in coronary flow (18%) in constant pressure perfusion, and an increase in perfusion pressure (208%) under constant flow perfusion. Thus, tissue deoxygenation has to be given due attention in the early development of calcium paradox, particularly in case of a constant pressure perfusion. Under constant flow perfusion, the physical stress due to high pressure perfusion against contracture may play an important role in the development of calcium paradox. This may be the first reported evidence for tissue anoxia in calcium paradox.
在钙反常过程中测定了大鼠心脏代谢和物理特性的早期变化。钙反常是在恒定灌注压力（60 mmHg）或恒定冠状动脉血流速率（9.8 ml/min）下诱发的。在补充钙后的30秒内，无论哪种情况，尽管ATP减少、ADP和AMP增加，但NADH增加。表面分光光度法显示肌红蛋白脱氧，从而表明心肌耗氧。这些变化在恒压灌注条件下更为明显。随着挛缩的迅速发展，恒压灌注时冠状动脉血流也减少了18%，恒流灌注时灌注压力增加了208%。因此，在钙反常的早期发展中，尤其是在恒压灌注的情况下，必须对组织脱氧给予应有的关注。在恒流灌注下，高压灌注对抗挛缩所产生的物理应激可能在钙反常的发展中起重要作用。这可能是首次报道的钙反常中组织缺氧的证据。
