ANTIOXIDANT PROPERTIES OF OMEPRAZOLE

Potential antioxidant properties of therapeutically achievable concent rations of the protonated, active form of omeprazole (OM) were investi gated in vitro at specific acidic pH values to mimic intragastric cond itions in the clinical setting. We found that OM is a powerful scaveng er of hypochlorous acid (HOCl) even at a drug concentration of 10 mu M at pH of 5.3 or 3.5. This effect is also evident in the presence of t he physiological HOCI scavenger ascorbate. Moreover, 10 and 50 mu M OM inhibit significantly both iron-and copper-driven oxidant damage at p H 5.3 and 3.5, respectively. Since oxidative stress is involved the ga stric injury of peptic ulcer and gastritis, it may be hypothesized tha t some therapeutical effects of OM could also be related to its antiox idant properties.