RESUMO
OBJECTIVE: To investigate the protection mechanism of reduced glutathione (GSH) in acute lung injury in rats with sepsis. METHODS: Sepsis in Sprague-Dawley (SD) rats were reproduced by cecal ligation and puncture (CLP). They were randomly divided into four groups, sham-operated group, model group, GSH treatment group and levofloxacin (LEV) treatment group. Heart blood of 7 rats in all groups was collected at 3, 6, 12, 24 hours after operation. The plasma levels of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) were measured. The lung ultrastructure changes were observed with electron microscope at 24 hours in all groups. RESULTS: Compared with the sham-operated group, the plasma level of TNF-alpha increased more obviously at 6 hours of the model group [(227+/-28) microg/L vs. (132+/-9) microg/L, P<0.01]. Compared with the model group, the plasma level of TNF-alpha in the GSH treatment group decreased obviously [(144+/-28) microg/L], and it was obviously lower than that of LEV treatment group [(214+/-48) microg/L , both P<0.01] . No obvious difference of plasma level of TNF-alpha was found at 3, 12, 24 hours among all the groups. Compared with the sham-operated group, the plasma level of IL-6 of the model group raised obviously at 3 hours [(267.65+/-72.87) microg/L vs. (135.43+/-40.08) microg/L, P<0.01]. In the GSH treatment group, the plasma level of IL-6 [(191.97+/-62.98) microg/L] was lower than that of the model group and the LEV treatment group [(268.75+/-74.67) microg/L, both P<0.05]. The plasma level of IL-6 was not obviously different among all groups at 6, 12, 24 hours. In the model group, the injury of pulmonary ultrastructure was obvious, especially in the mitochondria of the pulmonary cells. In the GSH treatment group, the change in ultrastructure of the lung was slight. CONCLUSION: TNF-alpha and IL-6 play significant role in the development of pulmonary ultrastructure injury in acute lung injury of septic rats. Treatment with GSH was effective in preventing such injury.