Effects of hydrogen saline on oxidative stress damage in rats brain tissues after cardiopulmonary resuscitation

Objective To investigate the effect and mechanism of hydrogen saline on oxidative stress damage in rats brain tissues after cardiopulmonary resuscitation (CPR). Methods Eighteen adult male pathogen-free Sprague-Dawley (SD) rats were randomly divided into control group (Con group), conventional resuscitation group (ROSC group) and hydrogen saline treatment group (ROSC+HRS group), with 6 rats in each group. All rats were asphyxiated by tracheal clip method to establish cardiac arrest (CA) model, and received first aid with CPR, electric defibrillation and adrenaline until return of spontaneous circulation (ROSC). The rats in ROSC+HRS group were intraperitoneally injected with 2% hydrogen saline (5 mL/kg for the first time and 3 mL/kg every 2 hours). The rats in Con group were only tracheal intubated and mechanical ventilated. The rats were sacrificed after ROSC for 12 hours, and the brain tissue was harvested to determine the contents of malonaldehyde (MDA), superoxide dismutase (SOD), and catalase (CAT). The protein expression of heme oxygenase-1 (HO-1) was determined with Western Blot, and the mRNA expression of HO-1 was determined with reverse transcription-polymerase chain reaction (RT-PCR). Results Compared with the Con group, the MDA was significantly elevated in ROSC group (nmol/mg: 8.15±0.11 vs. 3.68±0.16, P 0.05). Compared with the ROSC group, the MDA was significantly decreased in ROSC+HRS group (nmol/mg: 4.72±0.28 vs. 8.15±0.11, P < 0.05), the SOD and CAT were significantly elevated [SOD (U/mg): 83.02±1.10 vs. 69.30±2.39, CAT (U/mg): 85.07±1.94 vs. 74.38±1.65, both P < 0.05], HO-1 mRNA expression was significantly elevated (gray value: 3.200±0.200 vs. 1.383±0.194, P < 0.05), and the HO-1 protein expression was significantly elevated (gray value: 0.788±0.059 vs. 0.350±0.049, P < 0.05). Conclusions Oxidative stress damage is an important mechanism of CPR brain damage. Hydrogen saline can increase the expression of HO-1 in brain tissue, and decrease oxidative stress damage of brain after CPR. Key words: Brain damage; Hydrogen saline; Oxidative stress; Heme oxygenase-1