Nitric oxide (NO), produced by endothelial NO synthase, is recognised as a central antiinflammatory and antiatherogenic principle in the vasculature. Epidemiological and clinical studies have demonstrated that a growing list of natural products, as components of the daily diet or phytomedical preparations, may improve vascular function by enhancing NO bioavailability. In this article, we investigated antioxidant effects of propolis on biochemical parameters in kidney and heart tissues of acute NO synthase inhibited rats by Nω-nitro-l-arginine methyl ester (l-NAME). There was increase (p < 0.001) in the activities of catalase and malondialdehyde levels in the l-NAME treatment groups when compared with control rats, but NO levels were decreased in both kidney and heart tissues. There were statistically significant changes (p < 0.001) in these parameters of l-NAME + propolis treated rats as compared with l-NAME-treated group. In summary, propolis may influence endothelial NO production.
Keywords: Catalase; l-NAME; malondialdehyde; nitric oxide; propolis; rat.