Lead-induced hypertension in rats resulted in the upregulation of the gp91phox subunit of NAD(P)H oxidase in the left ventricle and the brain and compensatory upregulation of superoxide dismutase, Mn-SOD (SOD2) in the heart and Cu,Zn-SOD (SOD1) in the brain and kidney. Here, SOD2 is linked to hypertensive disorder.