Abstract: Objective To investigate the effects of hydrogen sulfide on autophagy and the apoptosis after acute spinal cord injury in rats. Methods Thirty-six adult male SD rats (250-300 g) were randomly divided into three groups (n=12 for each group): sham operation group (Sham group), spinal cord injury group (Model group) and hydrogen sulfide pre-treatment group (H2S group). Allen’ s method was used to establish the rat model of spinal cord injury. Rats of sham operation group received only laminectomy. Rats of H2S group received sodium hydrosulphide injection intraperitoneally (50 μmol/kg) 1h after spinal cord injury, and Model group was given the same amount of saline solution. Rats in the three groups were sacrificed 24 h after spinal cord injury, then the spinal cord was removed. The expressions of LC3, p70S6K and Cleaved caspase-3 were detected by Western blot assay. The expression of LC3 was also detected by immunofluorescence. The cell apoptosis was assessed by TUNEL stain. Results Compared with Sham group, the expression levels of LC3Ⅱ/LC3Ⅰand Cleaved caspase3 were increased in Model group, but the expression of p70S6K decreased and cell apoptosis increased in Model group (P <0.01). Compared with Model group, the expression levels of LC3Ⅱ/LC3Ⅰand Cleaved caspase-3 were decreased significantly, while the expression of p70S6K increased and cell apoptosis decreased significantly in H2S group (P < 0.01). Conclusion Hydrogen sulfide can inhibit autophagy and reduce cell apoptosis after acute spinal cord injury in rats.

Key words: acute spinal cord injury, H2S, autophagy, LC3, apoptosis, blotting, western