一氧化氮對過量銅所誘導水稻切離葉片氧化逆境之影響

Studies on the nitic oxide on oxidative stress of detached rice leaves induced by excess copper

游佳琪(Chia-Chi Yu)

指導教授 ： 高景輝

國立臺灣大學/生物資源暨農學院/農藝學研究所/碩士(2004年)

https://doi.org/10.6342/NTU.2004.01789

摘要

本論文係以水稻台中在來一號 (Oryza sativa L. Taichung Native 1, TN1) 切離葉片為試驗材料，探討一氧化氮對過量銅所誘導水稻切離葉片毒害之影響。
以水稻切離葉片蛋白質含量的降低為過量銅所引起之毒害指標。硫酸銅處理使水稻切離葉片 (1) 銅含量增加、 (2) 產生毒害、 (3) H2O2與MDA 含量增加、 (4) SOD與POX比活性增加及 (5) GR比活性降低。自由基清除劑 (GSH、SB及Tu) 可以抑制過量銅所造成水稻葉片毒害、MDA與H2O2含量增加、SOD與POX比活性增加及GR比活性之降低。
NO釋放劑SNP也可以抑制過量銅所造成之蛋白質含量降低、MDA與H2O2含量增加、SOD與POX比活性提高以及GR比活性降低。SNP處理同樣能消除因為硫酸銅誘導而產生的銨離子含量的增加、PAL與protease比活性的提高以及GS活性的降低。而NO清除劑c-PTIO則能去除SNP之保護作用，顯示SNP之作用確實是由一氧化氮所造成。NO降低過量銅所引起的水稻切離葉片的毒害可能是由於其清除H2O2所造成。

關鍵字

銅 ； 水稻 ； 切離葉片 ； 一氧化氮

並列摘要

The objective of this study was to investigate the effect of nitric oxide (NO) on the toxicity of detached rice leaves (Oryza sativa L. cv. Taichung Native 1) caused by excessive CuSO4.

Toxicity of detached rice leaves was determined by the decrease of protein content. Excessive CuSO4 treatment resulted in (1) increase in Cu content, (2) induction of toxicity, (3) increase in H2O2 and MDA contents, (4) increase in the specific activities of SOD and POX, and (5) decrease in the specific activity of GR. Free radical scavengers (GSH、SB and TU) reduced CuSO4-induced toxicity, CuSO4-increased H2O2 and MDA contents, CuSO4-increased specific activities of SOD and POX, and CuSO4-decreased specific activities of GR in detached rice leaves.

NO donor sodium nitroprusside (SNP) was effective in preventing CuSO4-induced toxicity, CuSO4-increased H2O2 and MDA contents, CuSO4-increased specific activities of SOD and POX, and CuSO4-decreased specific activities of GR. SNP also reduced CuSO4-increased NH4+ content, CuSO4-decreased GS activity, and CuSO4-increased specific activities of PAL and protease in detached rice leaves. The protective effect of SNP on CuSO4-induced toxicity, CuSO4-increased H2O2 and MDA contents, CuSO4-increased SOD, POX, PAL and protease specific activities, and CuSO4-decreased GS activity was reversed by c-PTIO, a NO scavenger, suggesting that the protective effect by SNP is attributable to NO released. Reduction of CuSO4-induced toxicity by NO in rice leaves is most likely mediated through it’s ability to scavenge H2O2 .

並列關鍵字

detached leaves ； nitric oxide ； Cu ； rice

參考文獻

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