Ethanol stimulates chemiluminescence from neutrophils in the liver

The production of free radicals in tissues can be continually monitored by measurement of low-level chemiluminescence. In these experiments the effects of ethanol on luminol (1 microM)-enhanced chemiluminescence were recorded in isolated perfused livers from control rats, and from rats that had undergone a 30-min period of ischemia, followed by 3 h of reinstitution of blood flow. Our previous experiments showed considerable neutrophil accumulation at this time. A routine concentration of 100 mM ethanol added after 20 min of perfusion with Krebs-Henseleit solution caused an increase in chemiluminescence of about 2000 cpm above the resting level (1600 cpm) in both control livers and livers from rats after 3 h of ischemia reperfusion in vivo. However, if ethanol was added to the perfusing medium of the isolated liver after at least 1 h of in vitro perfusion, then the magnitude of the response was very much greater (peak approximately 27000 cpm) in livers that had undergone ischemia reperfusion than in control livers (peak approximately 7000 cpm). Experiments combining addition of ethanol and the potent neutrophil stimulator, phorbol myristate acetate (PMA), plus the use of rat antineutrophil serum have shown conclusively that the very large chemiluminescent response to ethanol after prolonged in vitro perfusion is due to stimulation of neutrophil radical production.