Effect of hyperbaric oxygen on the apoptosis and the expression of caspase-3 mRNA in neonatal rats with hypoxic-ischemic brain damage

Objective To study the effect of hyperbaric oxygen (HBO) on the apoptosis and expression of Caspase-3 mRNA in neonatal rats with hypoxic-ischemic brain damage(HIBD),and to find out the possible mechanism of HBO treatment.Methods Healthy 7-day-old SD rats were randomly divided into 3 groups:normal control group ( n =8),HIBD group ( n =8),HIBD+HBO group ( n =8).The apoptosis and the expression of Caspase-3 mRNA were detected by TUNEL and in situ hybridization technique.Results There were no or little positive apoptotic cells and no or little expression of Caspase-3 mRNA in the normal control group,but much of those in the HIBD group.HBO therapy (HIBD+HBO group) can significantly decrease the positive apoptotic cells[(252.96±68.59) vs (342.24± 74.16), P 0.05] and weaken the expression of Caspase-3 mRNA.Conclusion The number of apoptotic cells and the expression of Caspase-3 mRNA increased obviously in the HIBD group,compared with the normal control group.HBO treatment can decrease the apoptotic cells and weaken the expression of Caspase-3 mRNA,which suggests that HBO probably has a neuronal protecting effect through the above mechanism.