title: In vivo studies of cellular energy state, pH, and sodium in rat liver after thermal injury.
abstract: In vivo 31P- and 23Na-magnetic resonance spectroscopy was used to measure phosphorus metabolites, intracellular pH, cytosolic free Mg2+, and intracellular Na+ in the liver of rats 24 h after 40% total body surface area full-thickness burn injury. Studies were performed during infusion of thulium (III) 1,4,7,10-tetraazacyclododecane N,N',N",N"'-tetra(methylenephosphonate), which served as the Na+ shift agent. Compared with the sham-burn group, there was a significant increase in hepatic intracellular Na+ along with a decrease in intracellular pH and free Mg2+. The ratio of intra- to extra-cellular Na+ increased, indicating a decreased Na+ gradient that may determine the hepatic transmembrane potential difference. Hepatic beta-ATP/P(i) also significantly decreased, which suggests that either ATP utilization is significantly accelerated or ATP synthesis is inhibited after the thermal injury. Of the cations measured (Na+, Mg2+, H+), the change in intracellular Na+ was most dramatic. This study demonstrates that major burn injury may cause profound changes in hepatic bioenergetics and ionic metabolism 24 h after injury and that intracellular Na+ may be a sensitive indicator of hepatic dysfunction 24 h after injury. Because these animals tolerated the shift reagent, thulium (III) 1,4,7,10-tetraazacyclododecane N,N',N",N"'-tetra(methylenephosphonate), nuclear magnetic resonance spectroscopy may prove valuable in monitoring intracellular cations in the liver after major injury.
authors.affiliation: Department of Surgery, Mary Nell and Ralph B. Rogers Magnetic Resonance Center, Dallas, Texas.
authors.forename: Z F
authors.initials: ZF
authors.lastname: Xia
authors.forename: J W
authors.initials: JW
authors.lastname: Horton
authors.forename: P Y
authors.initials: PY
authors.lastname: Zhao
authors.forename: N
authors.initials: N
authors.lastname: Bansal
authors.forename: E E
authors.initials: EE
authors.lastname: Babcock
authors.forename: A D
authors.initials: AD
authors.lastname: Sherry
authors.forename: C R
authors.initials: CR
authors.lastname: Malloy
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D001834:Body Water / Q000378:metabolism; D002056:Burns / Q000378:metabolism* / Q000473:pathology; D004734:Energy Metabolism / Q000502:physiology*; D006863:Hydrogen-Ion Concentration; D008099:Liver / Q000293:injuries* / Q000378:metabolism* / Q000473:pathology; D008274:Magnesium / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008564:Membrane Potentials / Q000502:physiology; D009942:Organometallic Compounds; D009943:Organophosphorus Compounds; D010759:Phosphorus Isotopes; D051381:Rats; D017207:Rats, Sprague-Dawley; D012964:Sodium / Q000097:blood / Q000378:metabolism*; D012975:Sodium Isotopes; D013932:Thulium
chemical_list: D009942:Organometallic Compounds; D009943:Organophosphorus Compounds; D010759:Phosphorus Isotopes; D012975:Sodium Isotopes; C069929:thulium(III) 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetramethylenephosphonate; D013932:Thulium; D012964:Sodium; D008274:Magnesium