DIRECT EVIDENCE OF NITRIC-OXIDE PRODUCTION FROM BOVINE AORTIC ENDOTHELIAL-CELLS USING NEW FLUORESCENCE INDICATORS - DIAMINOFLUORESCEINS

The measurement of nitric oxide (NO) is important for direct examinati on of the regulatory roles of NO in various biological systems, Diamin ofluoresceins (DAFs), new fluorescence indicators for NO, were applied to detect the release of NO from bovine aortic endothelial cells (ECs ), DAFs react with NO to yield the corresponding green-fluorescent tri azolofluoresceins, which provide the advantages of specificity, sensit ivity and a simple protocol for the direct detection of NO. Using thes e DAFs, we could detect the generation of NO not only from inducible N O synthase expressed in macrophages, but also from constitutive NO syn thase expressed in ECs. (C) 1998 Federation of European Biochemical So cieties.