Abstract: The experiments were conducted with the callus of Nitraria tangutorum Bobr. for studying the changes of lipid peroxidation and antioxidase activity under treatment with SNP(Sodium Nitroprusside), as a NO donor. Investigation of NO content using laser scanning confocal microscope (LSCM) technology showed that there was a significant increase of NO level in the callus of N. tangutorum Bobr. in response to SNP treatment, but a decrease induced by L-NNA. Remarkable reduce of MDA content was observed in N. tangutorum Bobr. callus treated with low SNP concentration, but 100 μmol·L^-1 SNP or 0.5 mmol·L^-1 L-NNA induced enhanced MDA content in comparison with the control. Compared to the control，SNP treatment induced increase in the amount of soluble protein, whereas decrease in proline content the callus of N. tangutorum Bobr.. SNP treatment resulted in increasing CAT and APX activities in a concentration-dependent manner. In addition, treatment with low SNP concentration reduced POD activity, but POD activity increased to 119% of contrast in callus treated with 50 μmol·L^-1 SNP. In conclusion, the results testified that exogenous NO induced synthesis of soluble protein, enhanced antioxidant capacity and antioxidase activity in the callus of N. tangutorum Bobr., suggesting that the protective effect of NO to N. tangutorum Bobr. cell was proved.

Key words: Nitraria tangutorum Bobr., callus, nitric oxide, lipid peroxidation, antioxidant enzyme