MEASUREMENT OF NITRIC-OXIDE RELEASE LN THE ISOLATED-PERFUSED RAT LUNG

In this study we have continuously measured real-time production of ni tric oxide (NO) in the isolated, perfused rat lung by using an NO moni tor (model NO-501, Inter Medical Co., Nagoya, Japan) with an NO-select ive resin microsensor. A stable NO response was obtained when the sens or was placed in the pulmonary artery or the pulmonary vein; in contra st, the tracings obtained from the lung periphery were unstable. Furth ermore, the NO release was higher when the isolated lungs were perfuse d with physiological salt solution rather than whole blood perfusion. Changes in NO production were also monitored in acute hypoxia and reox ygenation. Pretreatment with endotoxin (10mg/kg) potentiated the NO re lease observed, and this effect of endotoxin was further potentiated b y arginine (1 x 10(-4) M) and acetylcholine (1 x 10(-5) M) and counter ed by the NO synthase inhibitor, L-N-G-nitroarginine methyl ester (L-N AME; 1 x 10(-3) M). (C) 1995 Academic Press, Inc.