Hassinen I, Ito K, Nioka S, Chance B
Department of Medical Biochemistry, University of Oulu, Finland.
Biochim Biophys Acta. 1990 Aug 9;1019(1):73-80. doi: 10.1016/0005-2728(90)90126-o.
The calorigenic effect of fatty acids on the intact myocardium was investigated in isolated rat hearts perfused with a phosphate-free bicarbonate buffer. 31P-NMR spectra were accumulated in a Fourier transform high-field spectrometer during titration of the heart with varying concentrations of hexanoate. Oxygen consumption, coronary flow, left ventricular pressure development, heart rate and tissue surface fluorescence of nicotinamide-adenine nucleotides were monitored simultaneously. It was found that hexanoate within a range of 40 to 800 microM increased the reduction of NADH/NAD, increased oxygen consumption and increased the phosphocreatine/inorganic phosphate ratio in a concentration-dependent manner. The results suggest that the fatty acid-induced increase in oxygen consumption is not due to a primary effect on the cellular energy state resulting from a decrease in the P/O ratio or uncoupling of the mitochondria but due to an increase in the thermodynamic driving force.
在灌注无磷酸盐碳酸氢盐缓冲液的离体大鼠心脏中，研究了脂肪酸对完整心肌的产热效应。在用不同浓度的己酸盐滴定心脏的过程中，在傅里叶变换高场光谱仪中累积31P-NMR光谱。同时监测氧耗、冠状动脉流量、左心室压力发展、心率和烟酰胺腺嘌呤核苷酸的组织表面荧光。结果发现，40至800微摩尔范围内的己酸盐以浓度依赖的方式增加了NADH/NAD的还原、增加了氧耗并增加了磷酸肌酸/无机磷酸盐的比率。结果表明，脂肪酸诱导的氧耗增加不是由于对细胞能量状态的主要影响，这种影响是由P/O比率降低或线粒体解偶联导致的，而是由于热力学驱动力的增加。
