FIGURE 2.

Plasma enrichment of glutamine (A) and citrulline (B) after the continuous infusion of 2,3,3,4,4-[²H₅]- or [¹³C₅]-glutamine in mice. Values are means ± SEMs; n = 7. The addition of the M+4 and M+5 of glutamine due to the infusion of [²H₅]-glutamine was not different than the M+5 enrichment due to the infusion of [¹³C₅]-glutamine (5.89 compared with 5.85 mpe, respectively; P = 0.44). Likewise, citrulline M+4 + M+5 enrichment due to the infusion of the deuterated or carbon-labeled glutamine did not differ (0.68 and 0.71 mpe; P = 0.28). mpe, mole percent excess.