Wellard R M, Shehan B P, Adam W R, Craik D J
Renal Laboratory, Repatriation General Hospital, Heidelberg West, Australia.
Magn Reson Med. 1993 Jan;29(1):68-76. doi: 10.1002/mrm.1910290113.
Differences in the NMR detectability of 39K in various excised rat tissues (liver, brain, kidney, muscle, and testes) have been observed. The lowest NMR detectability occurs for liver (61 +/- 3% of potassium as measured by flame photometry) and highest for erythrocytes (100 +/- 7%). These differences in detectability correlate with differences in the measured 39K NMR relaxation constants in the same tissues. 39K detectabilities were also found to correlate inversely with the mitochondrial content of the tissues. Mitochondria prepared from liver showed greatly reduced 39K NMR detectability when compared with the tissue from which it was derived, 31.6 +/- 9% of potassium measured by flame photometry compared to 61 +/- 3%. The detectability of potassium in mitochondria was too low to enable the measurement of relaxation constants. This study indicates that differences in tissue structure, particularly mitochondrial content are important in determining 39K detectability and measured relaxation rates.
已观察到39K在各种切除的大鼠组织（肝脏、大脑、肾脏、肌肉和睾丸）中的核磁共振（NMR）可检测性存在差异。肝脏的NMR可检测性最低（通过火焰光度法测量，钾含量为61±3%），而红细胞的最高（100±7%）。这些可检测性的差异与相同组织中测量的39K NMR弛豫常数的差异相关。还发现39K的可检测性与组织的线粒体含量呈负相关。与从中提取线粒体的组织相比，从肝脏制备的线粒体显示出39K NMR可检测性大大降低，通过火焰光度法测量，钾含量为31.6±9%，而原组织为61±3%。线粒体中钾的可检测性过低，无法测量弛豫常数。这项研究表明，组织结构的差异，特别是线粒体含量，在决定39K可检测性和测量的弛豫速率方面很重要。
