Objective: Arterial hypertension is often associated with pathologies related with oxidative stress. Angiotensin converting enzyme (ACE) inhibitors have been used as a safe and effective treatment of hypertension and coronary heart disease. However, the significance of ACE inhibitor usage in hypertension-induced cerebrovascular and neurodegenerative diseases is still unknown. In this study, we aimed to investigate the effects of lisinopril, an ACE inhibitor, on oxidative stress and antioxidant enzyme activities in brain tissues of rats with L-NAME (N-omega-Nitro-L-Arginine Methyl Ester hydrochloride) induced hypertension.