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作 者 ：刘建新;王鑫;李博萍

期 刊 ：植物研究 2010年 30卷 1期 页码：37-41

关键词：一氧化氮；NaCl胁迫；抗坏血酸—谷胱甘肽循环；多裂骆驼蓬；

Keywords:Nitric oxide, NaCl stress, the ascorbate-glutathione cycle, Peganum multisectum,

摘 要 ：研究了外源一氧化氮(NO)供体硝普钠(SNP)对NaCl胁迫下多裂骆驼蓬幼苗抗坏血酸(ASA)谷胱甘肽(GSH)循环抗氧化系统及H₂O₂和丙二醛(MDA)含量的影响。结果表明，0.15 mmol·L^-1 SNP能提高300 mmol·L^-1 NaCl胁迫下多裂骆驼蓬幼苗叶片抗坏血酸过氧化物酶(APX)、谷胱甘肽还原酶(GR)和谷胱甘肽转硫酶(GST)活性，增加还原型抗坏血酸(ASA)和谷胱甘肽(GSH)含量，降低脱氢抗坏血酸(DHA)和氧化型谷胱甘肽(GSSG)含量，提高ASA/DHA、GSH/GSSG比率，降低H₂O₂和MDA水平，对单脱氢抗坏血酸还原酶(MDAR)和脱氢抗坏血酸还原酶(DHAR)活性无显著影响。NO信号转导途径关键酶鸟苷酸环化酶(GC)抑制剂亚甲基蓝(MB)逆转了SNP对盐胁迫下APX、GR、GST活性和ASA、GSH、DHA，H₂O₂、MDA含量及ASA/DHA、GSH/GSSG比率的调节效应。由此表明，NO可能通过GC介导的cGMP信号转导参与ASA-GSH循环活性氧清除系统的调节，从而缓解盐胁迫诱导的氧化伤害。

Abstract:The effects of spraying exogenous NO with the donor of sodium nitroprusside(SNP) on the ascorbate-glutathione cycle dependent antioxidant system and the contents of H₂O₂ and malondialdehyde(MDA) in Peganum multisectum Bobr under salt stress were investigated. The results showed that the activities of ascorbate peroxidase(APX), glutathione reductase(GR), glutathione-S-transferase(GST) and the contents of ascorbic acid(ASA) and reduced glutathione(GSH), the ratios of ASA/DHA and GSH/GSSG in leaves of P.multisectum with 0.15 mmol·L^-1 SNP treatment under 300 mmol·L^-1 NaCl stress were increased while the contents of oxidized ascorbic acid(DHA), oxidized glutathione(GSSG), H₂O₂ and MDA were decreased, the activities of monodehydroascorbate reductase(MDAR) and dehydroascorbate reductas(DHAR) were not affected under NaCl stress. However, the effects of SNP on the activities of APX, GR, GST, the contents of ASA, GSH, DHA，H₂O₂, MDA, and the ratios of ASA/DHA and GSH/GSSG under NaCl stress were reversed by methylene blue(MB), inhibitor of the key enzyme guanylyl cyclase(GC) during signal transfer of NO. It is suggested that NO is involved in regulation of the ascorbate-glutathione cycle dependent antioxidant system through cyclic guanosine monophosphate(cGMP) pathway to alleviate the oxidative damage of P.multisectum seedlings from salt stress.

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