Naritomi H, Kanashiro M, Sasaki M, Kuribayashi Y, Sawada T
Cerebral Circulation Laboratory, National Cardiovascular Center, Osaka, Japan.
Biophys J. 1987 Oct;52(4):611-6. doi: 10.1016/S0006-3495(87)83251-4.
The introduction of new paramagnetic shift reagents in the nuclear magnetic resonance (NMR) method has made it possible to distinguish intra- and extracellular ions in tissues or organs in vitro. We measured the intra- and extracellular 23Na and 1H in vivo in the gerbil brain and skeletal muscle by NMR spectroscopy employing the shift reagent, dysprosium triethylenetetraminehexaacetate (Dy[TTHA]3-). Without Dy(TTHA)3-, the 23Na and 1H signals were seen only as single peaks, but gradual intravenous infusion of Dy(TTHA)3- separated these signals into two peaks, respectively. The unshifted peaks reflected the intracellular 23Na and 1H signals, while the shifted peaks reflected the extracellular signals. In the brain spectra, an additional small peak, which represented intravascular signals, was detected and its intensity increased after injection of papaverine hydrochloride. The present method is advantageous over the microelectrode technique because of its nondestructiveness and its capability for obtaining intra- and extracellular volume information from measurements of the 1H spectra, the peaks of which reflect the intra- and extracellular water amounts. The intracellular Na+ increase associating with increased cellular volume after ouabain in the muscle was clearly visualized by this method. The technique is clearly of use for physiological and pathophysiological studies of organs.
核磁共振（NMR）方法中新型顺磁位移试剂的引入，使得在体外区分组织或器官中的细胞内和细胞外离子成为可能。我们采用位移试剂三乙烯四胺六乙酸镝（Dy[TTHA]3-），通过NMR光谱法在体内测量了沙鼠脑和骨骼肌中的细胞内和细胞外23Na及1H。在没有Dy(TTHA)3-时，23Na和1H信号仅表现为单峰，但逐渐静脉输注Dy(TTHA)3-分别将这些信号分离为两个峰。未位移的峰反映细胞内23Na和1H信号，而位移的峰反映细胞外信号。在脑谱中，检测到一个额外的小峰，它代表血管内信号，注射盐酸罂粟碱后其强度增加。本方法优于微电极技术，因为它具有非破坏性，并且能够通过测量1H谱获取细胞内和细胞外体积信息，1H谱的峰反映细胞内和细胞外水的含量。通过该方法可以清楚地观察到在肌肉中哇巴因作用后，细胞内Na+增加与细胞体积增大相关。该技术显然可用于器官的生理和病理生理研究。
