Antioxidant Effect of Tetrandrine on Cultured Rabbit Corpus Cavernosum Smooth Muscle Cells Injured by Hydrogen Peroxide

【Objective】 To investigate the antioxidant effects of tetradrine (Tet) on cultured corpus cavenosum smooth muscle cells (CCSMC) injured by hydrogen peroxide (H2O2). 【Methods】 The CCSMC were cultured in vitro and divided randomly into three groups: contrast group, H2O2 group, and Tet + H2O2 group. The effects of Tet on the viability of cell injured by H2O2 were assessed by 4,5-simethylthiazaoly colorimetric assay. The level of malondialdehyde (MDA), superoxide dismutase (SOD) activity and lactate dehydrogenase (LDH) release of CCSMC injured by H2O2 were detected by chemical colorimetry. 【Results】 After treatment with 1 mmol / L H2O2 for 4 h, the cell viability dropped from 100% to (48.57 ± 4.1)% (n = 8; P 0.01). While LDH release increased from (487.3 ± 78.6) U / L to (1105.5 ± 65.8) U / L (n = 8; P 0.01). The level of MDA increased from 3.8 ± 1.4 nmol·L-1·mg-1 to (77.3 ± 8.6) nmol·L-1·mg-1 (n = 8; P 0.01) and the SOD activity dropped to (30.7 ± 4.5) U / mL from (51.8 ± 5.9) U / mL that in contrast group (n = 8; P 0.01). However, treatment with different concentration of Tet (10-7-10-4 mol / L) could inhibit the damaging effects of H2O2, with increased cell viability and SOD activity (P 0.01), and decreased LDH release and MDA content (P 0.05 or P 0.01), respectively. 【Conclusion】 Tet has protective effect on CCSMC injured by H2O2, which might be related to enhancing the antioxidant abilities of CCSMC, and decreasing the injury of cell membrane by lipid peroxidation.