Tag Archives: sodium nitroprusside

Effect of sodium nitroprusside and S-nitrosoglutathione on pigment content and antioxidant system of tocopherol-deficient plants of Arabidopsis thaliana

N. M. Semchuk, Yu. V. Vasylyk, O. I. Kubrak, V. I. Lushchak

Vassyl Stefanyk Precarpathian National University, Ivano-Frankivsk, Ukraine;
e-mail: lushchak@pu.if.ua

Sodium nitroprusside (SNP) and S-nitrosoglutathione (GSNO) were used as a source of exogenous nitric oxide (NO) to investigate their effects on biochemical parameters and antioxidant enzyme response in leaves of wild type Columbia and tocopherol-deficient vte4 and vte1 mutant lines of Arabidopsis thaliana plants and possible tocopherol involvement in regulation of antioxidant response under NO-induced stress. SNP enhanced the activity of the enzymes, that scavenge hydrogen peroxide in leaves of all studied lines, and increased glutathione reductase and glutathione-S-transferase activity there. In addition, it decreased the intensity of lipid peroxidation in vte1 mutant line leaves. At the same time, GSNO increased the levels of protein carbonyls and inactivated enzymes ascorbate peroxidase, guaiacol peroxidase and dehydroascorbate reductase in almost all investigated plant lines. In contrast to wild type, GSNO increased superoxide dismutase activity and decreased catalase activity and chlorophyll a/b ratio in the leaves of two mutant lines. It can be assumed that tocopherols in some way are responsible for plant protection against NO-induced stress. However the mechanisms of this protection remain unknown.

The influence of heavy metal ions, spermine and sodium nitroprusside on ATP-hydrolases of cell membranes of rat colon smooth muscle

A. A. Kaplia

Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: kaplya@biochem.kiev.ua

The specific features of functional lability of the rat colon smooth muscle (CSM) АТР-hydrolases were studied. Na+,K+-AТРase activity is effectively inhibited by divalent ions of both transition (≥ 0,1 µM) and nontransition (≥ 1 µM) heavy metals in succession by efficiency: Cu2+ > Fe2+ ≥ Cd2+ (10 µM). Polyamine spermine (0,5-1,0 mM) is a weak  Na+,K+-AТРase inhibitor at saturation concentrations of ions and substrate. Sodium nitroprusside (1 mM) as nitric oxide-generating compound exhibits weak Na+,K+-AТРase inhibition only after prolonged preincubation with membranes. Mg2+-АТР-hydrolase activity in all cases is much more resistant to studied agents. Considering the example of the CSM Na+,K+-AТРase it is assumed that  enzyme has specific biochemical features that contribute to its role as a potential target and redox-sensor, mediating the pathological mechanisms of heavy metal intoxication and cell oxidative damage.

Effect of sodium chloride and nitroprusside on protein carbonyl groups content and antioxidant enzyme activity in leaves of corn seedlings Zea mays L.

Yu. V. Vasylyk1, N. M. Semchuk1, Ok. V. Lushchak2, V. I. Lushchak1

1Department of Biochemistry and Biotechnology,
2Botanical Gardens of Vasyl Stefanyk Precarpathian National University,
Ivano-Frankivsk, Ukraine;
e-mail: lushchak@pu.if.ua

The effect of sodium nitroprusside (SNP) and sodium chloride (NaCl) on protein carbonyl group content and activity of antioxidant enzymes was investigated in leaves of maize seedlings. Incubation with NaCl and SNP+NaCl increased the content of carbonyl proteins after 24 h. Treatment with SNP+NaCl during 48 h showed lower and after 72 h higher carbonyl protein content than that in the control. Catalase activity was higher in the leaves of SNP+NaCl-treated than in the leaves of SNP-treated seedlings after 24 h. Ascorbate peroxidase activity increased after incubation with 0.2 mM SNP for 24 h. Significant increment of guaiacol peroxidase activity was obtained in all treated groups in comparison with the control after 72 h. Glutathione-S-transferase activity increased after 48 h seedling treatment with NaCl or SNP and 72 h seedling incubation with NaCl. Under experimental conditions used, glutathione reductase activity was virtually not affected. It is proposed that SNP can be used to prevent salt-induced oxidative stress in maize.