Gut glutamine metabolism at different stages of sepsis in rats

To investigate gut glutamine metabolism and determine the effects of glutamine supplementation in different stages of sepsis in a rat model.

Sepsis was induced by cecal ligation and puncture (CLP), and control rats underwent a sham operation. In the first experiment, a continuous infusion of normal saline was started at the end of the operation. Intestinal blood flow, glutamine concentrations of the abdominal aorta and superior mesenteric vein (SMV) were measured, and gut glutamine extraction and flux were calculated 5 h after the sham operation, and 5 and 20 h after CLP, being groups Ia ( n = 9), Ib ( n = 8), and Ic ( n = 8), respectively. In the second experiment, animals received a continuous infusion of alanyl-glutamine instead of normal saline and were divided into groups IIa ( n = 8), IIb ( n = 8), and IIc ( n = 6). The same parameters were measured in each group and compared with those of the corresponding group in the first experiment.

In the first experiment, no significant difference in SMV blood flow was seen among the groups. The arterial glutamine concentration was increased in group Ic ( P < 0.05) compared with that in groups Ia and Ib. Gut glutamine extraction was significantly increased in group Ib ( P < 0.01) and significantly decreased in group Ic ( P < 0.05) compared with that in group Ia. In the second experiment, gut glutamine flux was significantly increased in group Ilb ( P < 0.01) compared with that in group Ib, but the increase did not reach statistical significance between groups Ia and IIa or between groups Ic and IIc.

These results indicate that intestinal glutamine uptake is increased and glutamine utilization is enhanced by glutamine supplementation in early sepsis.