Neurohr K J, Barrett E J, Shulman R G
Proc Natl Acad Sci U S A. 1983 Mar;80(6):1603-7. doi: 10.1073/pnas.80.6.1603.
Guinea pig heart metabolism was studied in vivo by 13C NMR at 20.18 MHz. High-quality proton-decoupled 13C NMR spectra with excellent signal-to-noise ratios and resolution could be obtained in 6 min. Natural-abundance spectra showed resonances that could be assigned to fatty acids, but glycogen was not seen. During intravenous infusion of D-[1-13C]glucose and insulin, the time course of myocardial glycogen synthesis was followed serially for up to 4 hr. Anoxia resulted in degradation of the labeled glycogen within 6 min and appearance of 13C label in lactic acid. Infusion of sodium [2-13C]acetate resulted in incorporation of label into the C-4, C-2, and C-3 positions of glutamate and glutamine, reflecting "scrambling" of the label expected from tricarboxylic acid cycle activity. Examination of the 31P NMR spectrum of the guinea pig heart in vivo demonstrated no change in the high-energy phosphates during the time periods of the 13C NMR experiments. Our studies indicate that 13C NMR is a unique non-destructive tool for the study of heart metabolism in vivo.
采用20.18 MHz的13C核磁共振技术在体研究豚鼠心脏代谢。在6分钟内即可获得具有出色信噪比和分辨率的高质量质子去耦13C核磁共振谱。天然丰度谱显示出可归属于脂肪酸的共振峰，但未观察到糖原。在静脉输注D-[1-13C]葡萄糖和胰岛素期间，连续跟踪心肌糖原合成的时程长达4小时。缺氧导致标记的糖原在6分钟内降解，并在乳酸中出现13C标记。输注[2-13C]乙酸钠导致标记掺入谷氨酸和谷氨酰胺的C-4、C-2和C-3位，反映了三羧酸循环活性预期的标记“重排”。对豚鼠心脏在体的31P核磁共振谱进行检测表明，在13C核磁共振实验期间高能磷酸盐没有变化。我们的研究表明，13C核磁共振是一种用于在体研究心脏代谢的独特非破坏性工具。
