Effects of hyperbaric oxygen therapy as hepatic preconditioning in rats submitted to hepatic ischemia/reperfusion injury.

PURPOSE To analyze the role of hyperbaric oxygen therapy as hepatic preconditioning in rats submitted to hepatic ischemia and reperfusion. METHODS Wistar rats were randomly divided into three groups: SHAM, rats submitted to surgical stress without hepatic ischemia and reperfusion, I/R, rats submitted to total hepatic pedicle ischemia for 30 min, followed by 5 min of reperfusion; HBOI/R, rats submitted to 60 minutes of hyperbaric oxygen therapy at 2 atm and immediately submitted to the experimental protocol of ischemia and reperfusion. Liver function was assessed by measuring serum alanine aminotransferase and aspartate aminotransferase, as well as mitochondrial function by determining states 3 and 4 of mitochondrial respiration, respiratory control rate and mitochondrial permeability transition (mitochondrial swelling). The results were analyzed by the Mann-Whitney test and all P-values <0.05 were considered significant. RESULTS There were significant differences in serum aspartate aminotransferase values in groups SHAM vs. HBOI/R, I/R vs HBOI/R, alanine aminotransferase in groups SHAM and I/R; State 3 in SHAM groups vs. I/R, SHAM vs. HBOI/R, State 4 in I/R vs HBOI/R groups, respiratory control rate in SHAM vs I/R groups; mitochondrial swelling in SHAM vs. I/R groups, and SHAM vs HBOI/R. CONCLUSION Hyperbaric preconditioning improved hepatic mitochondrial function and decreased serum markers of liver injury in the ischemia and reperfusion process.