MYOCARDIAL MICRODIALYSIS OF SALICYLIC-ACID TO DETECT HYDROXYL RADICALGENERATION DURING ISCHEMIA

We examined in vivo monitoring of hydroxyl radical ((OH)-O-.) generati on during myocardial ischemia for 30 min by occluding the left anterio r descending (LAD) in dog heart using a microdialysis technique. The h ydroxyl radical reacts with salicylate sind generates 2,3- and 2,5-dih ydroxybenzoic acids (DHBA) which can be measured electrochemically in picomole quantity by a high pressure liquid chromatography-electrochem ical (HPLC-EC) procedure. When the premature ventricular contraction ( PVC) occurred at almost 25 sec intervals, marked elevation of the leve ls of 2,3- and 2,5-DHBA was observed in the heart dialysate of 30-min ischemia. This study demonstrated the generation of (OH)-O-. in the ca nine heart subjected to 30-min ischemic insult.