Overactivation of brain angiotensin-converting enzyme (ACE)–angiotensin II (Ang II)–angiotensin II type 1 receptor (AT1R) axis has been found to play a important role in the development and maintenance of hypertension and then elevated oxidative stress in brain and increased the activity of sympathetic nervous system (Veerasingham and Raizada, 2003). This evidence concerns the gene ACE and hypertensive disorder.