Intact tissues and organs

Cultured and isolated cells 8.6.13 Intact tissues and organs... 

Phosphorus occurs predominantly as the isotope which has a nuclear spin value of 1/2 and is therefore visible in nuclear magnetic resonance (NMR) spectrometry. Phosphorus NMR ( P NMR) has been in use since the development of multinuclear, high-field Fourier-transform instruments in the late 1970s. The P NMR method is widely used, with both onedimensional (ID) and multidimensional techniques, in such diverse areas as the characterization of organic and inorganic molecular structures, the analysis of biological fluids, the determination of intracellular pH, the noninvasive study of intact tissues and organs, and quantitative assays of industrial... 

They provide evaluation of actions and effects on intact animal and organ/tissue interactions. 

On the basis of this concept, one might expect a poison to be relatively uniform in its toxic effect on a series of intact animals because, in the different animals, many different tissues and organs would be involved and the chance exists that the resistance of one tissue might be compensated for by the susceptibility of another. Since from our previous discussions we realize that every individual animal is made up of a coordinated set of organs and tissues, each distinctive (quantitatively) in size, composition, and enzymic make-up, we should expect the greatest interindividual differences to be observed when single tissues from different animals are tested in parallel. This exemplifies the principle which appears to be an important one for our discussions. We expect to find the most striking evidences for biochemical individuality when we look at details, rather than at crude summations. 

Tissue slices and whole organ culture maintain many spatial aspects of the intact tissue and, like whole cells, maintain the linkage between Phase I and Phase II enzymes (Sipes et al., 1987). Precision-cut tissue slices are more easily and reproducibly prepared than primary hepatocytes. However, viability limitations often restrict studies to a few hours duration. Histological examination of the material after exposure to a xenobiotic is possible with tissue slices. 

The Study of the Metaholism of Labeled Substrates by NMR Spectroscopy of Intact Cells, Tissues, and Organs... 

The utility of labeled substrates and nmr spectroscopy for the non-destructive situ analysis of metabolic pathways In Intact cells, tissues, and organs, depends on the following considerations ... 

The invention of the surface coil and the development of NMR probes containing life-support systems have made it possible to observe high-energy phosphates in intact tissues and whole organisms. P NMR has been used for the safe, noninvasive detection of disease states in tissues without risk to the patient. Metabolic products soluble in the cytoplasm of skeletal muscle, heart, kidney, brain, and eye have all been qualitatively observed and identified. With the appropriate use of standards, determination of relaxation times, and performance of the necessary instrument calibrations, quantitative results can be comparable to those obtained in wet-chemical assays. The protonation/deprotonation equilibrium of phosphates influences the P chemical shift, facilitating the noninvasive determination of tissue pFi. 

Kinetic Models of Metabolism in Intact Cells, Tissues, and Organisms Barbara E. Wright and Patrick J. Kelly... 

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