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    The effect of experimentally induced carbon dioxide pneumoperitoneum on intra-abdominal and intra-esophageal pH
    (Tubitak Scientific & Technical Research Council Turkey, 2009) Soyer, Tutku; Aydos, Tolga Resat; Aktuna, Zuhal; Korkut, Oguzhan; Ozmanoglu, Goekhan; Hancerliogullari, Oeymen; Cakmak, Murat
    Aim: An experimental study was performed to evaluate the effect of CO2 pneumoperitoneum on intra-abdominal (IA) and intra-esophageal (IE) pH. Material and methods: The study included 18 Wistar rats. In the control group (n = 6) a pH catheter was inserted into the peritoneal cavity via a left upper quadrant incision and another catheter was inserted into the lower esophagus via the oral route. Pre- and post-insufflation IA and IE pH were recorded every 5 min for 1 h. In the experimental groups, in addition to pH catheters, a 16-G catheter was inserted into the abdomen above the umbilicus. In the O-2 group (n = 6) 95% O-2 and 5% CO2 were insufflated with a pressure of 10 mmHg. In the CO2 group (n = 6), CO2 was insufflated with the same pressure and duration. Results: In the CO2 group, IA and IE pH values significantly decreased (P < 0.05). IA pH values decreased in the CO2 group when compared to the control and O-2 groups (P < 0.05). There was not a significant difference in IE pH between the CO2 group and the other groups. Conclusion: CO2 insufflation decreased IA pH values. Decreased pH values obtained with continuous recordings of the esophagus may have been related to increases in intra-abdominal pressure, rather than the metabolic effects of CO2 pneumoperitoneum.
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    Effect of phototherapy on gastrointestinal smooth muscle activity and oxidative stress
    (Springer, 2011) Soyer, Tutku; Aliefendioglu, Didem; Aktuna, Zuhal; Caglayan, Osman; Aydos, Tolga Resat; Cakmak, Murat
    Aim To evaluate the effect of phototherapy on gastrointestinal smooth muscle activity and oxidative stress. Methods Wistar albino rats (n = 18, in the first 7 days of life) weighing 7 +/- 2 g with both sexes were included in the study. The animals were randomized into three groups. In control group (CG), median laparotomy was performed to obtain 1 cm of jejunum, terminal ileum and colonic segments. In the phototherapy group (PTG), led phototherapy with a wave density of 40 mu w/cm(2)/nm were used (Bilitron 3006, Fanem, Brasil). The efficacy surface of phototherapy was 30-40 cm and the exposure distance was 30 cm. The duration of phototherapy was 24 h. Sham group (SG) received white light with the same wave density and exposure distance. The oxidative stress markers and contraction responses were investigated from intestinal segments obtained from experiments. Results The jejunum segments showed significantly lowered contraction response to carbachol in SG when compared to CG and PTG (p < 0.05). Decreased contractile response to KCl was detected in both SG and PTG in terminal ileum segments. MDA levels showed no difference between groups (p > 0.05). Total sulfhydryl (T-SH) levels were found significantly increased in PTG when compared to CG and SG (p < 0.05). When NO levels were evaluated, NO levels were found decreased in PTG and SG with respect to CG (p < 0.05). Conclusion PT may cause various alterations in oxidant/antioxidant system in intestinal segments. Unlike to clinical findings, decreased contractile responses were detected in rat gastrointestinal smooth muscles after PT.
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    The Effects of Beta-blockers on Endothelial Nitric Oxide Synthase Immunoreactivity in the Rat Corpus Cavernosum
    (Elsevier Science Inc, 2010) Dogru, Mehmet Tolga; Aydos, Tolga Resat; Aktuna, Zuhal; Korkusuz, Petek; Zeybek, Dilara; Gorgu, Nart; Basar, Mehmet Murad
    OBJECTIVES To explain the mechanism of the effects of beta-blockers on endothelial dysfunction and release of nitric oxide from the endothelium. METHODS A total of 72 Sprague-Dawley rats were divided into 9 different groups as follows: group 1: control (n = 10), group 2: metoprolol (Beloc) 100 mg/kg/d (n = 7), group 3: carvedilol (Dilatrend) 50 mg/kg/d (n = 7), group 4: nebivolol (Vasoxen) 10 mg/kg/d (n = 6), group 5: estrogen receptor (ER) antagonist ICI 182.780 (Fluvestrant) 50 mu g/g (n = 10), group 6: nebivolol +ER antagonist (n = 8), group 7: androgen receptor (AR) antagonist (flutamide) 20 mg/kg (n = 7), group 8: nebivolol + AR antagonist (n = 7), and group 9: DMSO (solvent for ER antagonist) (n = 10). All beta-blockers were applied with gastric gavage after dilution with 5 mL of serum physiological; ER and AR were both applied intraperitoneally (i.p.) for 14 days. In the isolated rat cavernous tissues, endothelial nitric oxide synthase (eNOS) and ER and AR immunoreactivity were analyzed quantitatively. One-way analysis of variance and Tukey test were used for statistical analysis. RESULTS Although increased eNOS immunoreactivity was observed with nebivolol and nebivolol-flutamide in endothelial cells laying cavernous tissue, a lower score was observed after ICI-182.780 application, when compared with control cases. AR immunoreactivity in cavernosal endothelium was clearly higher with nebivolol. Higher H score and ER immunoreactivity were observed in the cavernous endothelium and smooth muscles in the nebivolol, carvedilol, and metoprolol groups when compared with control cases. CONCLUSIONS We showed that eNOS activity was increased in the nebivolol and nebivolol-flutamide groups, whereas it was decreased in the ICI 182.780 group. We believe that an ER-dependent mechanism triggered by nebivolol played a role in nitric oxide formation. UROLOGY 75: 589-597, 2010. (C) 2010 Elsevier Inc.
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    Effects of ozone therapy and taurine on ischemia/reperfusion-induced testicular injury in a rat testicular torsion model
    (Tubitak Scientific & Technical Research Council Turkey, 2014) Aydos, Tolga Resat; Basar, Mehmet Murad; Kul, Oguz; Atmaca, Hasan Tank; Uzunalioglu, Tuba; Kisa, Ucler; Efe, Oguzhan Ekin
    Background/aim: To investigate the effect of ozone and/or taurine treatment comparatively on testicular damage due to ischemia/reperfusion (I/R) injury in an experimental torsion model in rats. Materials and methods: Adult Wistar rats with and without torsion/detorsion were used. In order to monitor the effect of ozone and/or taurine treatment on testicular damage due to I/R injury, following histopathological investigation apoptotic indexes were scored by TUNEL method. Moreover, tumor necrosis factor receptor 1 (TNFR1), caspase 3, caspase 8, endothelial nitric oxide synthase (eNOS), tumor necrosis factor alpha (TNF alpha), and cytochrome C immunostainings were performed and the levels of malondialdehyde, glutathione peroxidase, superoxide dismutase, catalase, total sulthydryl, and nitric oxide were determined in the testicular tissue. Results: Intraperitoneal ozone and/or taurine treatment prevented both histopathological damage and increase in the apoptotic index. Torsion did not exert an effect on the levels of TNFa and cytochrome C. Ozone and/or taurine treatment prevented increases in TNFR1, caspase 3, and caspase 8. The level of oxidative stress markers was unchanged. The increases in NO level and eNOS expression were prevented by ozone and/or taurine treatment in I/R groups. Conclusion: Using ozone therapy and/or taurine before reperfusion may be a solution for germ cell degeneration resulting from testicular torsion and related infertility.