Figure 5.

¹H NMR analysis of Lactate and Alanine from the Liver of Rats Receiving [2,3‐¹³C]pyruvate. Rats received [2,3‐¹³C]pyruvate through a tail vein and liver was harvested after 8 min. ¹³C enrichments in lactate and alanine were measured by ¹H NMR analysis of liver tissue extracts. ¹H NMR spectrum from a fed rat (A) shows resonances of lactate C3 (at 1.32 ppm) and alanine C3 (at 1.47 ppm) with dominant peaks from proton attached to ¹²C (H‐¹²C) and small satellite peaks from proton attached to ¹³C (H‐¹³C). Fed animals have higher levels of alanine and lactate in the liver compared with fasted animals (B) whereas they have lower ¹³C enrichments in both lactate and alanine than fasted animals (C). *P < 0.001. n = 5–7 in each group.