Correction: Liver AMP-Activated Protein Kinase Is Unnecessary for Gluconeogenesis but Protects Energy State during Nutrient Deprivation

Exercise training adaptations in liver glycogen and glycerolipids require hepatic AMP-activated protein kinase in mice

“…Following a one-hour acclimation period, an 80 μl arterial blood sample was obtained to determine natural isotopic enrichment of plasma glucose. Immediately after this sample acquisition, a stable isotope infusion protocol was initiated to allow for the quantification of endogenous glucose production and associated oxidative fluxes as previously performed (5,6,(26)(27)(28)(29)(30). Briefly, a 2 H 2 O (99.9%)-saline bolus containing [6,6-2 H 2 ]glucose (99%) was infused over 25 minutes to concurrently label the H 2 O pool and provide a [6,6-2 H 2 ]glucose prime (440 μmol•kg -1 ).…”

“…The details of the in vivo metabolic flux analysis methodology employed in these studies have been described previously (27). In summary, a reaction network was constructed using Isotopomer Network Compartmental Analysis (INCA) software (31).…”

“…The reaction network defined the carbon and hydrogen transitions for hepatic glucose production and associated oxidative metabolism reactions. The flux through each network reaction was determined relative to citrate synthase flux (V CS ) by minimizing the sum of squared residuals between simulated and experimentally determined MIDs of the six fragment ions previously described (27,32). Flux estimates were repeated 50 times from random initial values.…”

“…Goodness of fit was assessed by a chi-square test (p = 0.05) with 34 degrees of freedom. Confidence intervals of 95% were determined as previously described (27,32). Mouse body weights and the [6,6-2 H 2 ]glucose infusion rate were used to determine absolute values.…”

Exercise training adaptations in liver glycogen and glycerolipids require hepatic AMP-activated protein kinase in mice

“…Following a one-hour acclimation period, an 80 μl arterial blood sample was obtained to determine natural isotopic enrichment of plasma glucose. Immediately after this sample acquisition, a stable isotope infusion protocol was initiated to allow for the quantification of endogenous glucose production and associated oxidative fluxes as previously performed (5,6,(26)(27)(28)(29)(30) ]glucose prime. Four arterial blood samples (100 μl) were obtained 90-120 minutes following the [U-13 C]propionate bolus (time = 0-30 minutes of treadmill running) to determine arterial blood glucose using an Accu-Chek® glucometer (Roche Diagnostics, Indianapolis, IN, USA) and to perform 2 H/ 13 C metabolic flux analysis.…”