The result of the present study clearly showed that the levels of SOD and catalase are remarkably decreased in rats treated with lead acetate. Lead acetate is known to cause free radical damage in tissues by two mechanisms: Increased generation of ROS, including hydroperoxides, singlet oxygen and hydrogen peroxides, and by Doxorubicin cost causing direct depletion of antioxidant reserves [20] and [21]. The observed decrease in circulating antioxidants and decrease in serum total antioxidants confirm the lead acetate-induced depletion of antioxidants [22]. All antioxidant enzymes including SOD and catalase decreased significantly in mitochondrial and post-mitochondrial

fraction of testis of lead and cadmium treated rats [19]. There is a significant

decrease in the activity levels of antioxidant enzymes superoxide dismutase and catalase in the testes of lead exposed rats [23]. In the present study, when the cinnamon and lead acetate was administrated to rats, the level of SOD was increased compared to its level in rats treated only with lead. The activities of liver SOD and catalase was significantly reduced in the carbon tetrachloride intoxicated group, while it was significantly elevated in the groups pretreated with either water or ethanol extracts of cinnamon find more [24]. Generally the effects of cinnamon have not yet been fully identified on reproductive system. This study concentrated on the effect of cinnamon extract on several reproductive parameters after lead exposure and its ability to correct the adverse effect of lead on seminal picture and testicular structure in rats. The improvement of reproductive parameters after cinnamon administration should be explained. One of the possible explanations is that concentration

of LH, FSH and testosterone hormones have been increased significantly after cinnamon administration [25]. This effect could be due to the presence of compounds in cinnamon which affect the hypothalamus-pituitary axis and has thus increased concentrations of these hormones. The researches done by Shagauo and Davidson GNAT2 [26] also showed that cinnamon is capable of releasing LH hormone by affecting hypothalamus axis and increasing the secretion rate of GnRH hormone. Also, they proposed that GnRH cause proliferation of sex cells by increasing the Leydig cell activities in adult rats. In another explanation, Parivzi and Ellendorff [27] showed that cinnamaldehyde extracted from cinnamon increase norepinephrine and this hormone can increase the release of nitric oxide. Cinnamaldehyde release cAMP with connecting calcium in cell membrane and cause increase in norepinephrine secretion. Norepinephrine increase LH secretion with activation of nitric oxide. Nitric oxide affects hypothalamus axis and release gonadotropin hormone (GnRH). Gonadotorpin hormones increase secretion of other hormones such as LH and FSH of pituitary gland. LH hormone affects Leydig cells and this cells release testosterone hormone.