[Scavenging effects of cyproheptadine on oxygen free radicals].

The scavenging effects of cyprohepdadine (Cyp), an antiserotonin-antihistaminic agent with significant calcium channel blocker activity, on oxygen free radicals were studied. Cyp was found to significantly scavenge the hydroxyl radical (.OH) produced by Fenton reaction (Fe(2+)+H2O2) (EC50 = 54 mumol/L) and inhibit the rate of .OH generation (IC50 = 22 mumol/L). The inhibitory effects of Cyp were significantly more potent than those of mannitol, a specific .OH scavenger, with EC50 of 22.7 mmol/L and 10.7 mmol/L respectively. Cyp was also shown to have certain scavenging effect on superoxide anion (O2-.) produced by peritoneal polymorphonuclear leukocytes (PMNs) in rats (IC50 = 179 mumol/L). These results suggest that the anti-myocardial injury activity of Cyp may be, at least partially, related to its scavenging effects on oxygen free radicals.