Analysis the effect of hyperbaric oxygen preconditioning on neuronal apoptosis, Ca2+ concentration and caspases expression after spinal cord injury in rats.

OBJECTIVE: To investigate the effects of hyperbaric oxygen preconditioning (HBO-PC) on neuronal apoptosis, Ca2+ concentration, and Caspases expression after spinal cord injury (SCI) in rats. MATERIALS AND METHODS: A total of 36 rats were randomly divided into control group (CON group), hyperbaric oxygen preconditioning group (HBO-PC group) and spinal cord injury group (SCI group), with 12 rats in each group. Rats in group HBO-PC were given HBO-PC intervention before modeling. SCI model was established by modified Allen method in group HBO-PC and group SCI. Basso-Beattie-Bresnahan (BBB) locomotor rating scale and motor evoked potential (MEP) examination were used to assess the neurological function. The expression of apoptosis gene caspase (3, 7, 8, 12) mRNA was detected by reverse transcription-polymerase chain reaction (RT-PCR). The concentration of Ca2+ in spinal cord tissue of each group was detected. RESULTS: CON group, HBO-PC group, and SCI group were gradually diminishing in BBB score and potential value and amplitude of MEP, respectively. The differences between groups were statistically significant (p<0.05). The expressions of Caspase-3 and 7, 8 and 12 mRNA in SCI group were significantly higher than those in CON group and HBO-PC group, respectively (p<0.05). There was no significant difference between CON group and HBO-PC group (p>0.05). The concentrations of Ca2+ in the CON group, HBO-PC group and SCI group were gradually increased; differences between groups were statistically significant (p<0.05). CONCLUSIONS: HBO-PC can reduce the loss of motor function of SCI rats, which may inhibit the activation of endoplasmic reticulum pathway of neural apoptosis, and reduce the calcium overload through inhibiting the expressions of pro-apoptotic proteins (Caspase-3/7/8/12), thus reducing the cell apoptosis and protecting neurons.