23Na and 39K nuclear magnetic resonance studies of perfused rat hearts. Discrimination of intra- and extracellular ions using a shift reagent.
23Na and 39K nuclear magnetic resonance studies of perfused rat hearts. Discrimination of intra- and extracellular ions using a shift reagent.
复制标题
灌注大鼠心脏的 23Na 和 39K 核磁共振研究。
DOI：
10.1016/s0006-3495(85)83769-3
复制
发表时间：
1985
影响因子：
3.4
通讯作者：
Smith,TW
中科院分区：
文献类型：
--
作者：
Pike,MM;Frazer,JC;Dedrick,DF;Ingwall,JS;Allen,PD;SpringerJr,CS;Smith,TW
在灌流介质中没有和存在下场移位试剂Dy(TTHA)3-的情况下，获得了灌流的大鼠心脏的高分辨~(23)Na和~(39)K核磁共振(核磁共振)谱。证据表明，Dy(TTHA)3-基本上进入所有细胞外空间，但不进入细胞内空间。因此，它可以用来区分这些空间中离子的共振。支持这一结论的实验包括抑制Na+/K+泵的干预措施，如在灌流液中加入哇巴因和将K+排除在灌流液中。在每个实验中，与细胞内钠相对应的一个峰的强度增加。在后一种实验中，当灌流液中的K+浓度恢复到正常时，这种增加被逆转。当灌流液中的钙离子浓度也恢复正常时，原本静止的心脏就会恢复跳动。在不停跳的心脏中，Na+/K+泵没有被抑制，细胞内Na+共振的强度不到预期的20%。虽然数据比较稀疏，但细胞内K+信号的核磁共振可见度似乎不超过20%。
High-resolution 23Na and 39K nuclear magnetic resonance (NMR) spectra of perfused, beating rat hearts have been obtained in the absence and presence of the downfield shift reagent Dy(TTHA)3- in the perfusing medium. Evidence indicates that Dy(TTHA)3- enters essentially all extracellular spaces but does not enter intracellular spaces. It can thus be used to discriminate the resonances of the ions in these spaces. Experiments supporting this conclusion include interventions that inhibit the Na+/K+ pump such as the inclusion of ouabain in and the exclusion of K+ from the perfusing medium. In each of these experiments, a peak corresponding to intracellular sodium increased in intensity. In the latter experiment, the increase was reversed when the concentration of K+ in the perfusing medium was returned to normal. When the concentration of Ca2+ in the perfusing medium was also returned to normal, the previously quiescent heart resumed beating. In the beating heart where the Na+/K+ pump was not inhibited, the intensity of the intracellular Na+ resonance was less than 20% of that expected. Although the data are more sparse, the NMR visibility of the intracellular K+ signal appears to be no more than 20%.