硝基-L-精氨酸干扰了镉还原法/格里斯反应法测定一氧化氮生成量的实验。

Nitro-L-arginine inteferes with the cadmium reduction of nitrate/griess reaction method of measuring nitric oxide production.

作者信息

Nithipatikom K, Pratt P F, Campbell W B

机构信息

Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI, USA.

出版信息

Eur J Clin Chem Clin Biochem. 1996 Feb;34(2):133-7. doi: 10.1515/cclm.1996.34.2.133.

DOI:10.1515/cclm.1996.34.2.133

PMID:8833645

Abstract

Nitro-L-arginine is used as an inhibitor of nitric oxide synthase in many biological Systems. Nitric oxide (NO) is unstable and degrades to nitrite NO(2)- and nitrate NO(3)-. The colorimetric reaction of N0(2)- with Griess reagent is commonly used to measure NO(2)-. NO(3)- may be measured as NO(2)- following reduction by cadmium or cadmium/copper. We found that bradykinin increased the formation of NO(2)- by bovine coronary endothelial cells. Nitro-L-arginine further increased the formation of NO(2)-. This increase is due to the interference of nitro-L-arginine in determination of NO(3)- by the cadmium reduction to NO(2)- and Griess reagent reaction. Incubation of nitro-L-arginine with cadmium or cadmium/copper produced a product that reacts with Griess reagent to form a compound that has an absorption spectrum identical to the product formed by NO(2)- and Griess reagent. Caution must be exercised when using the NO(2)-/NO(3)- measurement by the Griess reaction to assess inhibition of nitric oxide synthase by nitro-L-arginine.

摘要

在许多生物系统中，硝基-L-精氨酸被用作一氧化氮合酶的抑制剂。一氧化氮（NO）不稳定，会降解为亚硝酸盐NO₂⁻和硝酸盐NO₃⁻。NO₂⁻与格里斯试剂的比色反应常用于测定NO₂⁻。NO₃⁻可在经镉或镉/铜还原后作为NO₂⁻进行测定。我们发现缓激肽会增加牛冠状动脉内皮细胞中NO₂⁻的生成。硝基-L-精氨酸进一步增加了NO₂⁻的生成。这种增加是由于硝基-L-精氨酸在通过镉还原为NO₂⁻并与格里斯试剂反应来测定NO₃⁻的过程中产生了干扰。硝基-L-精氨酸与镉或镉/铜孵育会产生一种产物，该产物与格里斯试剂反应形成一种化合物，其吸收光谱与NO₂⁻和格里斯试剂形成的产物相同。在使用格里斯反应测定NO₂⁻/NO₃⁻以评估硝基-L-精氨酸对一氧化氮合酶的抑制作用时必须谨慎。