CLINICS 2011;66(1):137-142 Tissue parameters CAT(k/g tissue) GSH (mmol/g protein) GPx (mmol/g protein) MDA (mmol/g protein) NO (mmol/g tissue) Table 1 - CAT and GPx activities, GSH, MDA and NO levels in the contralateral testis in all groups. Protective effect of sildenafil citrate on contralateral testis injury Yıldız H et al. Group 1 (n = 7) 14.38 ¡ 1.16* 1.59 ¡ 0.03{ 23.07 ¡ 1.20{ 0.60 ¡ 0.02{1 31.11 ¡ 0.491 Group 2 (n = 10) 11.41 ¡ 1.16{ 1.50 ¡ 0.151 19.69 ¡ 2.201 0.73 ¡ 0.03{ 33.10 ¡ 0.22{ Group 3 (n = 10) 13.97 ¡ 1.13*{ 1.94 ¡ 0.25" 23.43 ¡ 5.19{ 0.51 ¡ 0.071 31.93 ¡ 0.741" Group 4 (n = 10) 12.22 ¡ 3.31{ 1.58 ¡ 0.34{1 20.57 ¡ 4.03{1 0.58 ¡ 0.08{1 32.27 ¡ 0.64{1 *{Within rows: means with different supercript letters differ significantly (p,0.01). {1"Within rows: means with different supercript letters differ significantly (p,0.05). Date are expressed as mean ¡ SEM. Windows. Results were considered statistically significant at p,0.05. RESULTS Biochemical analysis The results of testicular CAT and GPx activities and GSH, MDA and NO levels in contralateral testis in all groups are shown in Table 1. Contralateral testicular tissue GSH (p,0.05) level, CAT (p,0.01) and GPx (p,0.05) activities in group 2 were lower, whereas the NO level was higher (p,0.05) than in the group 1. The level of MDA in group 2 was increased, although the change was not statistically significant. GSH (p,0.05) level and GPx (p,0.05) activity were significantly higher and MDA level was significantly lower (p,0.05) in the contralateral testis of group 3 than in those of group 2. In group 3, contralateral testicular CAT and GPx activities and GSH, MDA and NO levels were similar to those of group (sham) 1. The testicular GPx and CAT activities and GSH, MDA and NO levels in the contralateral testis in group 4 were not significantly different from those of group 2 (p.0.05). Histopathologic evaluation When the structure of the testis was histopathologically examined, it was observed that the histological appearance of testicular tissues of group 1 was normal (Figure 1a). There were some histopathological changes such as degeneration, desquamation, disorganization in germinal cells, interstitial oedema and capillary congestion and hemorrhage in the conralateral testis of rats in group 2 (Figure 1b). These histopathological changes were also present to a similar extent in contralateral testis of rats from group 4 (Figure 1d). However, these histopathological changes were not sig- nificantly obvious in group 3 (Table 2, Figure 1c). Figure 1 - (a) Normal morphological appearance seminiferous tubule in contralateral testis of group 1 (H&E, 2006). (b) Degeneration, desquamation and disorganization in germinal cell along with interstitial oedema, capillary congestion and hemorrhage in group 2 (H&E, 2006). (c) Normal morphological appearance seminiferous tubule in group 3 (H&E, 2006). (d) Degeneration, desquamation, disorganization and reduction in germinal cell along with interstitial oedema, capillary congestion and hemorrhage in group 4 (H&E, 2006). 139