Lead-induced hypertension. III. Increased hydroxyl radical production

Lead-induced hypertension has previously been shown to be closely associate d with an increase in reactive oxygen species in low lead (100 ppm)-treated rats. The present study has attempted to define the specific moiety involv ed by noting the blood pressure (BP), reactive oxygen species (MDA-TBA), hy droxyl radical, and nitrotyrosine responses to infusion of the reactive oxy gen species scavenger dimethylthiourea. Dimethylthiourea, a reputed scaveng er of hydroxyl radical, normalized BP and MDA-TBA in the lead-treated rats but had no effect in normal control animals. MDA-TBA, hydroxyl radical, and nitrotyrosine, the tissue end product of peroxynitrite, were reduced to or toward normal by dimethylthiourea. The results, therefore, are consistent with the suggestion that either hydroxyl radical or peroxynitrite may be th e reactive species affected by lead. Am J Hypertens 2001;14:169-173 (C) 200 1 American Journal of Hypertension. Ltd.