Spatial heterogeneity of the metabolic response of RIF-1 tumors to a vasoactive agent evaluated in vivo by one-dimensional 31P chemical-shift imaging.
Localized 31P NMR spectroscopy was used to evaluate the spatial heterogeneity of the metabolic response of RIF-1 tumors to hydralazine. Volume localized 31P spectra were obtained from subcutaneous RIF-1 tumors using one-dimensional chemical-shift imaging, before and 20 min after treatment with 5 mg/kg hydralazine, administered intravenously. Following treatment all of the tumors showed an overall decrease in the ratio of nucleoside triphosphate (NTP) to inorganic phosphate (Pi) and a decrease in pH. However, spatial localization revealed that the reduction in NTP/Pi was not uniform within some tumors. This was partly due to regional differences in the levels of metabolites existing before treatment. Normal tissue adjacent to the tumor did not show a significant decrease in high-energy metabolites or pH.
Bhujwalla
Z M
ZM
Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
Blackband
S J
SJ
Wehrle
J P
JP
Glickson
J D
JD
D000818:Animals; D004734:Energy Metabolism / Q000187:drug effects*; D006830:Hydralazine / Q000494:pharmacology*; D009682:Magnetic Resonance Spectroscopy; D051379:Mice; D008809:Mice, Inbred C3H; D008815:Mice, Inbred Strains; D009374:Neoplasms, Experimental / Q000378:metabolism* / Q000473:pathology; D009711:Nucleotides / Q000032:analysis / Q000378:metabolism; D010710:Phosphates / Q000032:analysis / Q000378:metabolism; D010725:Phosphocreatine / Q000032:analysis / Q000378:metabolism
D009711:Nucleotides; D010710:Phosphates; D010725:Phosphocreatine; D006830:Hydralazine