Hydrogen sulfide antagonizes corticosterone-induced neurons and synapses damages in the hippocampus of depression rat models

Objective To explore the effect of hydrogen sulfide (H2S) on corticosterone (CORT)-induced neuronal and synaptic damages in the hippocampus of depression rat models. Methods Adult male SD rats were randomly divided into 4 groups: control group, CORT group, low-concentration NaHS (30 μmol/kg) treatment group and high-concentration NaHS (100 μmol/kg) treatment group (n=10). CORT (40 mg/kg) was subcutaneously injected into the rats from the later three groups for 28 d to establish depression models. After administration of CORT for 14 d, the control rats and CORT rats were treated with normal saline (5 mL/kg, ip) for 14 d, rats in the later two groups were treated with NaHS (30 and 100 μmol/kg/d, ip) for 14 d. The depressive-like behaviors were evaluated by sucrose preference test, the neuronal pathological changes in the hippocampus CA3 area were observed by HE staining, the neuronal apoptosis in the hippocampus was observed under microscope using Tunel staining, the protein expressions of Bcl-2, Bax and synaptophysin in the hippocampus were quantified by Western blotting, and the content of Caspase-3 was analyzed by ELISA. Results After administration of CORT for 28 d, rats from the CORT group exhibited decreased sucrose preference, disordered arrangement and sparse morphology as well as increased amount of apoptotic neuron in hippocampal CA3 area as compared with those in the control group with significant differences (P 0.05). Conclusion H2S can effectively improve the damage of hippocampal neurons and synapses in CORT rats. Key words: Depression; Hydrogen sulfide; Corticosterone; Hippocampus; Neuron; Synapse