Glutamine and glutamate kinetics in humans

• DOI: 10.1152/ajpendo.1986.251.1.e117
• Publication Date: 2017-12-21T18:42:48Z
• Authors: D. Darmaun; D. E. Matthews; D. M. Bier
• Keywords: Glutamic acid

To study glutamate and glutamine kinetics, 4-h unprimed intravenous infusions of L-[15N]glutamate, L-[2-15N]glutamine, L-[5-15N]-glutamine were administered to healthy young adult male subjects in the postabsorptive state. Arterialized-venous blood samples drawn analyzed for 15N enrichments. The fractional turnover rates tracer-miscible pools fast, 8.0 2.8% min-1, respectively. pool accounted less than one-tenth estimated free body. plasma amino N, N amide appearance 83 +/- 22 (means SD), 348 33, 283 31 mumol X kg-1 h-1, rate was 20% slower rate, indicating that transaminase is an active pathway human metabolism. From measurement transfer tracer 15N, we found only 5% synthesized cells released into derived from intracellular had mixed with plasma. These data demonstrate intravenously tracers or do not mix thoroughly pools, their measured kinetics reflect transport through rather whole-body fluxes.