Abstract:

Objective To investigate the effects of intravenous administration of glutamine (Gln) on secretion suppression of RAW 264.7 cells induced by mesenteric lymph in rats with sepsis. Methods SD rats were randomized into sham-operation group (Sham group), sepsis group (CLP group) and Gln group, with 10 rats in each group. Sepsis model was established by cecal ligation and puncture in CLP group and Gln group. Within 10 minutes after model establishment, 0.75 g/kg Gln was administered via single tail-vein injection in Gln group, while the same amount of normal saline was administered in Sham group and CLP group. Mesenteric lymph was obtained from 5 rats in each group, and blood samples were taken from the other rats 6 h after model establishment in each group. RAW264.7 cells were incubated with lymph for 4 h in each group, and the supernatants were harvested. The concentrations of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in mesenteric lymph and supernatants were measured by ELISA, and the concentrations of Gln in mesenteric lymph and D-lactate in plasma were determined by spectrophotometric assay. Results The concentrations of TNF-α and IL-6 in mesenteric lymph in CLP group and GLN group were significantly higher than those in Sham group (P<0.05). The concentrations of TNF-α and IL-6 in supernatants in CLP group were significantly lower than those in sham group (P<0.05), while the concentration of TNF-α in supernatants in Gln group was significantly higher than that in CLP group (P<0.05). There was no significant difference in the concentrations of Gln in mesenteric lymph among three groups (P>0.05). The concentration of D-lactate in plasma in Gln group was significantly lower than that in CLP group (P<0.05). Conclusion Secretion of RAW264.7 cells activated by LPS can be suppressed by mesenteric lymph in rats with sepsis, which can be partially alleviated by Gln treatment.

Key words: glutamine, sepsis, mesenteric lymph, macrophage, tumor necrosis factor-α, interleukin-6