Proton magnetization transfer effect in rat liver lactate.
Off-resonance lactate magnetization transfer (MT) experiments were performed on the in situ rat liver under perfused and ischemic conditions. A significant MT effect for lactate methyl protons was observed. The effect was larger for the ischemic condition than for the perfused condition, and was largest in the blood-filled ischemic livers. The size of the motionally restricted lactate pool, determined using a two-pool model fit, was estimated to be about 1% in perfused livers and about 1.8-2.5% after more than 1 hr of onset of ischemia, suggesting that lactate in liver is almost fully NMR-visible. The MT data for both the perfused and the ischemic condition appeared to be better approximated when assuming a superLorentzian lineshape for the immobile pool rather than a Gaussian lineshape. Finally, the experiments demonstrated a coupling between the lactate methyl and water protons, which may be mediated by macromolecules.
Dresselaers
Tom
T
Biomedische NMR-Eenheid, Faculteit Geneeskunde, Katholieke Universiteit Leuven, Gasthuisberg, Herestraat 49, B-3000 Leuven, Belgium.
Bergans
Niki
N
Van Hecke
Paul
P
Vanstapel
Florent
F
D000818:Animals; D007511:Ischemia; D007773:Lactates / Q000032:analysis*; D008099:Liver / Q000033:anatomy & histology / Q000098:blood supply / Q000737:chemistry*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D014867:Water
D007773:Lactates; D014867:Water