T1 of 129Xe in blood and the role of oxygenation
T1 of 129Xe in blood and the role of oxygenation
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DOI：
10.1006/jmre.1999.1836
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发表时间：
1999-09-01
影响因子：
2.2
通讯作者：
Jolesz, FA
中科院分区：
文献类型：
--
作者：
Albert, MS;Kacher, DF;Jolesz, FA
在作者之前的实验中，将超极化的xie -129溶解在新鲜血液样本中，发现T-1强烈依赖于氧合水平，随着氧合水平的增加，T-1在脱氧样本中约为4 s，在含氧样本中约为13 s。曾志华等（1997）。另一方面，Reson. 126, 79-86)最近报道了使用超极化的xie -129产生“血液泡沫”的极长T-1值，并发现氧合降低了T-1。在他们的实验中，超极化的Xe-129在气相（在血液泡沫气泡内）和气泡表面的溶解相之间持续快速交换，需要进行复杂的分析才能提取有效的血液T-1。在本研究中，通过使用溶解在全血和溶红细胞（RBC）悬浮液中的热极化xie -129，避免了超极化xie -129交换动力学的并发症。在全血T-1测量期间，在整个实验过程中，样品被轻轻地连续搅拌，以避免沉淀。氧合发现明显增加血液中Xe-129的T-1，正如最初测量的那样，它将RBC共振转移到更高的频率。一氧化碳也有类似的效果，但效果更强。(C) 1999学术出版社。
In previous experiments by the authors, in which hyperpolarized Xe-129 was dissolved in fresh blood samples, the T-1 was found to be strongly dependent on the oxygenation level, the values increasing with oxygenation: T-1 was about 4 s in deoxygenated samples and about 13 s in oxygenated samples. C. H. Tseng et al. (1997, J. Magn. Reson. 126, 79-86), on the other hand, recently reported extremely long T-1 values using hyperpolarized Xe-129 to create a "blood foam" and found that oxygenation decreased T-1. In their experiments, the continual and rapid exchange of hyperpolarized Xe-129 between the gas phase (within blood-foam bubbles) and the dissolved phase tin the skin of the bubbles) necessitated a complicated analysis to extract the effective blood T-1. In the present study, the complications of hyperpolarized Xe-129 exchange dynamics have been avoided by using thermally polarized Xe-129 dissolved in whole blood and in suspensions of lysed red blood cells (RBC). During T-1 measurements in whole blood, the samples were gently and continuously agitated, for the entire course of the experiment, to avert sedimentation. Oxygenation was found to markedly increase the T-1 of Xe-129 in blood, as originally measured, and it shifts the RBC resonance to a higher frequency. Carbon monoxide has a similar but somewhat stronger effect. (C) 1999 Academic Press.