Measurement of nitric oxide, nitrite and nitrate using a chemiluminescence assay:an update for the year 2000

This review deals with the measurement of nitric oxide (NO) using the chemiluminescence assay. A preliminary discussion is offered to explain the chemical basis for this assay and emphasize the importance of measuring NO. After reviewing some practical aspects and caveats of the chemiluminescence assay, we review its application in a variety of research and clinical settings, such as measurement of breath NO and serum nitrates. The importance of avoiding confounding effects of dietary nitrates when assessing the NO system in humans is discussed and new data are provided on the confounding effects of atmospheric NO on measurement of breath NO. The utility and ease of the chemiluminescence assay for these applications is contrasted with the challenge of using chemiluminescence for correlation of vascular tone and NO production, studies in which real-time measurements are required. Although the chemiluminescence assay is one of the most reliable, rapid and reproducible assays available, it is optimal for gas phase measurements and may be suboptimal for measurement under certain circumstances. This chapter complements several more general reviews of the methodology for measuring NO.