Ozone preconditioning and exposure to ketamine attenuates hepatic inflammation in septic rats

INTRODUCTION: The objective of this study was to evaluate the interaction between ozone oxidative preconditioning and the anesthetic ketamine on cytoplasmic nuclear factor κB (NF-κB) levels in a rat endotoxic shock model. MATERIAL AND METHODS: Forty Wistar rats were randomly divided into 5 groups: I – control group; II – rats intraperitoneally (i.p.) treated with LPS; III – rats treated with LPS and then treated with ketamine; IV – animals pre-treated with O(3)/O(2) mixture for 5 days, then treated with LPS for 24 h followed by infusion with ketamine; V – O(3)/O(2) pre-treatment, as described above for IV, followed by LPS infusion, and then 0.9% saline. In addition to histological examination of the liver, the levels of NF-κB were determined by SABC immunohistochemistry in each group. RESULTS: Histological damage was observed in the lipopolysaccharide (LPS) group. It was characterized by hepatic disarray, hepatic lobule distortion, congestion of liver sinusoids, hepatocyte swelling and necrosis, and granulocyte infiltration. These changes were not obvious in the O(3)/O(2) + LPS + ketamine group. The normal control group had low activity of NF-κB, but that activity was markedly increased in the LPS group (p < 0.05). The NF-κB level was significantly decreased in the O(3)/O(2) + LPS + ketamine group (p < 0.05) when compared with the ketamine-treated group, and was almost equal to the control group. CONCLUSIONS: We confirmed that the preconditioning effect of ozone enhances the biological effectiveness of ketamine by altering NF-κB activity, which may play an important role in sepsis-induced liver injury in rats.