(A) Total plasma acetate concentration (mmol/L) and (B) 13C isotopic enrichment (%) measured from high-resolution 1H NMR spectra following [2-13C]acetate infusion (TR = 10 s, 32 averages per time point). The time courses were found to be dependent on the constant continuous infusion rate of the labeled substrate. Error bars represent standard deviation. The rate of acetate infusion was 0.5, 1.0, 1.5 and 1.75 g/kg/hr for groups 1, 2, 3 and 4 respectively.