Figure 3.

GC in WT or G6pc2 KO islets isolated from CF mice and incubated in 5 mmol/L D7-glucose. A: The average relative abundance of lower mass isotopomers (M + 1 to M + 6) of the 1,2,5,6-di-isopropylidene propionate derivative fragment in the media from WT (black squares) or KO (white circles) islet incubations at 24 and 72 h. The relative abundances are corrected for natural stable isotope labeling (35) and normalized to the total labeled glucose signal from M + 1 to M + 7. The average relative abundance of the 24-h KO samples was subtracted from baseline values to correct for the isotopic purity of the D7-glucose tracer. In all experiments where tracer control samples were analyzed, the MID of the 24-h KO samples was nearly identical to the MID of the pure D7-glucose tracer (Supplementary Table 1). B: The average estimated abundance ± SEM of the [1,3,4,5,6,6-²H₆]glucose isotopomer with deuterium loss at C2 in the media from WT (black bar) or KO (white bar; all experiments reported zero abundance) islet incubations at 72 h. C: Average GC ± SEM, reported as a percentage of v_net. WT islets at 24 h, n = 4; WT islets at 72 h, n = 4; KO islets at 24 h, n = 4; KO islets at 72 h, n = 4 incubations of 100 islets. *P < 0.05 vs. WT islets. hr, hours.