Hindawi Publishing Corporation Oxidative Medicine and Cellular Longevity Volume 2013, Article ID 674593, 7 pages http://dx.doi.org/10.1155/2013/674593 Research Article Effects of Single Exposure of Sodium Fluoride on Lipid Peroxidation and Antioxidant Enzymes in Salivary Glands of Rats Paula Mochidome Yamaguti, Alyne Simões, Emily Ganzerla, Douglas Nesadal Souza, Fernando Neves Nogueira, and José Nicolau Departamento de Biomateriais e Biologia Oral, Faculdade de Odontologia, Universidade de S˜ ao Paulo, 05508-000 S˜ ao Paulo, SP, Brazil Correspondence should be addressed to Alyne Sim˜ oes; lysimoes@usp.br Received 7 February 2013; Revised 3 April 2013; Accepted 4 April 2013 Academic Editor: Kota V. Ramana Copyright © 2013 Paula Mochidome Yamaguti et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Many studies suggest that fuoride exposure can inhibit the activity of various enzymes and can generate free radicals, which interfere with antioxidant defence mechanisms in living systems. To further the understanding of this issue, this present study examined the efects of low-dose fuoride treatment on the activity of enzymatic antioxidant superoxide dismutase (SOD) and catalase (CAT), as well as the levels of lipid peroxidation (LPO) in the parotid (PA) and submandibular (SM) salivary glands of rats. Rats were injected with a single dose of sodium fuoride (NaF) (15 mg F − /kg b.w.) then euthanized at various time intervals up to 24 hours (h) following exposure. NaF exposure did not cause signifcant diferences in SOD or CAT activity or LPO levels in PA glands compared to control. Conversely, SM glands presented increased SOD activity afer 3 h and decreased SOD activity afer 1, 12, and 24 h, while LPO was increased afer 6, 12, and 24 h of the NaF injection. Tere were no signifcant diferences in the CAT activity in the groups studied. Our results demonstrated that NaF intoxication caused oxidative stress in salivary glands few hours afer administration. Tese changes were more pronounced in SM than in PA gland. 1. Introduction Fluoride is widely regarded as the cornerstone of modern preventive dentistry. Because of its cariostatic properties, fuoride has been increasingly added to alternative delivery systems, such as toothpastes and mouth rinses, so that expo- sure of populations to fuoride other than through fuoridated water supplies and foodstufs has become signifcant [1]. Te widespread use of these fuoridated products, in addition to its ubiquitous presence in the environment, has renewed consideration of the margin which exists between safe and toxic levels of fuoride exposure [2, 3]. Although the most pronounced efects of fuoride intake are manifested in bones and teeth, it is also known to cross cell membranes by simple difusion and enter sof tissues causing adverse efects on cell metabolism and function [1, 4–6]. In sof tissues, its concentration is proportional to the plasma concentration [7]. Salivary glands are important secretory organs, vital to various processes occurring in the oral cavity. Teir secretory products have an utmost importance for several physiological functions, playing a critical role in oral and systemic health by monitoring, regulating, and maintaining the integrity of the oral hard and sof tissues [8]. Te major salivary glands of both humans and rodents consist of three pairs of macroscopic glands: parotid (PA), submandibular (SM), and sublingual [9]. Studies with low doses of NaF administered to exper- imental animals have been shown to induce a number of alterations in the metabolism of their salivary glands. Some of these metabolic alterations include increases in glycogen content in SM glands [10] and higher levels of 3  ,5  cyclic AMP (cAMP) in PA and SM glands [11] as well as promoting the release of high molecular weight mucins from the SM gland [12]. Fluoride is also known to inhibit the activity of