Demonstration of the Formation of Hydroxyl Radicals in Acute Myocardial Infarction in Man Using Salicylate as Probe

Dihydroxybenzoic acid (DHBA) derivatives of acetylsalicylic acid (ASA) are formed in vivo by the action of the hydroxyl radical (OH.). In order to evaluate the possible formation of OH(.) in acute myocardial infarction (AMI) in man, 9 consecutive patients with a first episode of AMI (8 males, 1 female, mean age 50.3 years), treated with rt-PA, and 8 healthy volunteers (7 males, 1 female, mean age 29.8 years) were studied. All subjects received 100 mg ASA p.o. daily; venous blood samples were taken 30 min after the first dose (time 0) and then at 3-, 6-, 12-, 24- and 48 h and 5 days. Serum was analyzed by HPLC and electrochemical detection for 2,3- and 2,5-DHBA contents. 2,3-DHBA was present in all subjects with AMI and undetectable in healthy volunteers at all time points studied. Serum levels of 2,5-DHBA did not show statistically significant differences between AMI patients and healthy volunteers. These data support the hypothesis that hydroxyl radicals are formed during AMI in man.