Determination of absolute phosphate metabolite concentrations in RIF-1 tumors in vivo by 31P-1H-2H NMR spectroscopy using water as an internal intensity reference. Magn Reson Med 1992 Nov;28(1):105-21
Date
11/01/1992Pubmed ID
1435214DOI
10.1002/mrm.1910280111Scopus ID
2-s2.0-0026486423 (requires institutional sign-in at Scopus site) 33 CitationsAbstract
The absolute metabolite quantification method of Thulborn and Ackerman [J. Magn. Reson. 55, 357 (1983)] in which the tissue water proton signal is used as an internal intensity standard and its more recent variation in which NMR peak intensities are referenced to that of the natural abundance deuterium signal of water [Li et al., SMRM Abstr. 2, 825 (1988); Song et al., Magn. Reson. Med. 25, 45 (1992) have been implemented to obtain absolute phosphate metabolite concentrations in subcutaneous RIF-1 tumors during untreated growth and following treatment with 5-fluorouracil. The equivalence of these two hydrogen isotopes as intensity standards and the validity of their use in the determination of absolute metabolite concentrations in vivo by NMR has been demonstrated. On matched in vivo and extract tumor samples (n = 5), excellent agreement has been obtained between nucleoside triphosphate concentrations determined by NMR and those derived by HPLC analysis for the control tumors. Following 3 days of untreated growth, absolute concentrations of phosphate metabolites in RIF-1 tumors (n = 10) decreased significantly, except for the Pi concentration which did not vary. For the treated tumors (n = 10) there were no changes in metabolite concentrations except for a decrease in the PCr and, possibly, Pi concentrations. The PCr/Pi ratio in the latter tumors did not change. These observations suggest that changes in absolute metabolite concentrations may be more sensitive indices of response to therapy than changes in metabolite peak amplitude ratios, a parameter commonly used to express in vivo NMR data.
Author List
Shungu DC, Bhujwalla ZM, Li SJ, Rose LM, Wehrle JP, Glickson JDMESH terms used to index this publication - Major topics in bold
AnimalsBody Water
Chromatography, High Pressure Liquid
Fibrosarcoma
Fluorouracil
Magnetic Resonance Spectroscopy
Mice
Mice, Inbred C3H
Neoplasm Transplantation
Neoplasms, Radiation-Induced
Phosphates
