The data provided in literature reveal the complex biologically-active properties of polyphenols: antioxidant, anti-inflammatory, platelet antiaggregant, hypocholesterolemic, vasorelaxant. Due to their anthocyanins content, both Aronia melanocarpa and Sambucus nigra may have beneficial effects on the evolution and complications of arterial hypertenison. The experiment was conducted on five groups of white Wistar rats that enjoyed Aronia and Sambucus extract protection without suffering from drug-induced high blood pressure versus those that suffered from L-NAME induced high blood pressure. Their blood pressure as well as their SOD and GSH-Px expressed antioxidant status were measured on a weekly basis throughout the experiment, and their kidneys were sampled for a histological examination performed at the end of the experiment. The antioxidant capacity was either highly statistically significant for Aronia versus the purely high blood pressure group, or just statistically significant for Sambucus; moreover, the high blood pressure group treated with Aronia proved more protected (p<0.001) than the unprotected group and more highly statistically significant than the group that received Sambucus. The anatomic-pathological examination of the kidney sample revealed alterations such as chronic lymphocytic inflammatory infiltrate, hydropic degeneration injuries, perivascular fibrosis. These alterations were considerable in the high blood pressure group, whereas in the polyphenol protected groups they were much diminished. The considerable oxidative stress revealed in the high blood pressure rats was favorably modulated by vegetable polyphenols delivery. The histological examination conducted on the kidney samples supported the vessel protection effect of the two extracts.