Analysis of Intact Tissue with ³¹P NMR

Abstract

Since the pioneer paper of Moon & Richards in 1973 recording the 31p NMR spectrum of red blood cells (63), application of 31 P NMR to biologi­ cal systems has become very popular. Studies have ranged from the simple observation of anaerobic metabolism to the elegant combination of physiol­ ogy and spectroscopy demonstrated by Dawson et al (27) on frog muscle. Some reviews appeared on this topic (12, 30, 37). The low number of metabolites that contain phosphorus at levels that can be seen in the spectra (>0.5 mM in 1 5 min of observation time) differentiates phosphorus NMR from carbon and proton NMR, where the vast number of carbonand proton-containing compounds, except under special circumstances, yield complicated spectra that are not easily interpretable (26). The 31 P spectra obtained in all tissues examined are relatively uncomplicated and hence readily interpretable. With the demon­ stration of the feasibility of studying intact tissue, a door has been opened that allows the examination of many critical issues in biochemistry and physiology from a totally new angle. We document how this has ranged from the identification of previously undetected phosphates to tests of hypotheses of bioenergetics. 1