NMR STUDIES OF CATION TRANSPORT ACROSS BIOMEMBRANES

在这项建议中，我们寻求继续展示 浅谈应用变位试剂(SR)技术的重要性 我们已将其发展为23Na和39K核磁共振波谱 一种组织。SR的使用允许区别对待 生物金属阳离子的跨膜核磁共振信号。这个，在 反过来，为阳离子的潜在定量提供了条件 跨膜血药浓度及连续监测 运输。我们建议合成和测试新的SR，寻求 提高有效性、相对特异性等。我们还 建议测试新的松弛试剂(RR)。我们打算携带 仔细测量阳离子的核磁共振可见度 来自不同组织中不同隔室的信号。我们希望 为了继续探讨运输过程的性质，我们 可以通过这种方法观察到它们的生物学和医学 后果。因此，我们计划扩展我们对被动和 人红细胞和酵母中主动的Na+和K+转运。 对于后者，我们想测试我们认为是新发现的 离子转运与磷代谢的关系。 我们打算继续我们对灌流的、跳动的大鼠的研究 心。我们可以监测心肌细胞的Na+负荷 在一系列不同的干预之后。组合SR和 RR实验将使我们能够研究明显的 这些干预措施对间质的其他影响 和血管空间。我们还提出了新的SR实验 在活体大鼠脑内。这些都承诺有可能分析出 血脑屏障(BBB)的通透性 不同大脑的体积和离子浓度 车厢，以及Li+跨境运输的监测 BBB。我们的实验主要采用标准的体外和体内 高分辨率核磁共振的活体方法学，在高场(更高 大于或等于7T)中存在的稳定磁性同位素 自然资源丰富。这项工作涉及到物理学的各个方面， 物理和无机化学、生物化学、生物物理学和 生理学，并在许多研究中产生了影响 病理情况，包括心脏病和情感性 精神错乱。

In this proposal, we seek to continue to demonstrate the importance of the application of the shift reagent (SR) technique which we have developed to the 23Na and 39K NMR spectroscopy of tissue. The use of SR allows the discrimination of the transmembrane NMR signals of biological metal cations. This, in turn, provides for the potential quantitation of cation concentration and the continual monitoring of transmembrane transport. We propose to synthesize and test new SR, seeking increased effectiveness, compartimental specificity, etc. We also propose to test new relaxation reagents (RR). We intend to carry out careful measurements of the NMR-visibility of the cation signals from different compartments in different tissues. We wish to continue to explore the nature of the transport processes we can observe by this approach and their biological and medial consequences. Thus, we plan to extend our studies of passive and active Na+ and K+ transport in human erythrocytes and yeasts. With the latter, we want to test what we think is a newly found relationship between ion transport and phosphorus metabolism. We intend to continue our studies of the perfused, beating rat heart. We can monitor the Na+ -loading of the heart myocytes after a number of different interventions. Combination SR and RR experiments will allow us to investigate the apparent additional consequences of these interventions on the interstitial and vascular spaces. We also propose new SR experiments on the in vivo rat brain. These promise the possibilities of assaying the permeability of the blood-brain barrier (BBB), the relative volumes and ion concentrations of the different brain compartments, and the monitoring of transport of Li+ across the BBB. Our experiments mostly employ the standard ex vivo and in vivo methodology of high-resolution NMR, at high fields (greater than or equal to 7 T), of stable magnetic isotopes present in natural abundance. This work involves aspects of physics, physical and inorganic chemistry, biochemistry, biophysics, and physiology, and has ramifications in the study of a number of pathological conditions including heart disease and affective disorders.