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    Effect of SWL on renal hemodynamics: could a change in renal artery contraction-relaxation responses be the cause?
    (Springer, 2012) Yilmaz, Erdal; Mert, Cagatay; Keskil, Zuhal; Tuglu, Devrim; Batislam, Ertan
    The aim of this study was to reveal the effect of shock wave lithotripsy (SWL) on renal artery contraction-relaxation responses and the relation of this effect with renal hemodynamics. Twenty-four rabbits are divided into six different groups. The first two groups evaluated as the control groups. After isolating the kidneys, we applied phenylephrine (Ph) and acetylcholine (Ach) in the first group and sodium nitroprusside (SNP) and histamine (H) in the second group. In the third, fourth, fifth and sixth groups, 14.5 kV shock wave (SW) was focused on the left kidneys. We adjusted the number of shocks to a total of 500, 1,500, and 3,000 SW, in the third, fourth and fifth groups, respectively. After isolating the kidneys, Ph, Ach was given in groups 3, 4 and 5. In the sixth group, to get the SNP and the H responses, 3,000 shocks modality was utilized. Marked contractile responses were obtained by phenylephrine in the control group. In kidneys that were exposed to 500 shocks SWL procedures, a decrease in contractile responses and hence, in perfusion pressures in different concentrations of phenylephrine was noted. However, a notable change in relaxation responses occurred after 3,000-shock applications. No difference in relaxation responses to nitroprusside, a direct vasodilating agent, was observed in any group, compared to the control group. Another cause of deterioration of renal hemodynamics after SWL can be attributed to the reduction in renal artery contraction-relaxation responses that result in the vascular smooth muscle and endothelial damage.
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    The Effect of Whole Gut Irrigation on Contractile Responses of Guinea Pig Gallbladder, Ileum, and Tissue Cholecystokinin Levels
    (Georg Thieme Verlag Kg, 2014) Turkmen, Feyza; Soyer, Tutku; Keskil, Zuhal; Kisa, Ucler; Aslan, Mustafa; Senyucel, Mine; Cakmak, Murat
    Aim An experimental study was performed to evaluate the effect of whole gut irrigation (WGI) solutions on contractile responses of the gallbladder and ileum and also on tissue cholecystokinin (CCK) levels. Materials and Methods Thirty guinea pigs were enrolled into five groups including control group (CG) and WGI group (saline physiologic [SP], Ringer lactated [RL], polyethylene glycol [PEG], and dibasic sodium phosphate [DNP]). After median laparotomy, the distal esophagus was ligated and SP, PEG, RL, and DNP infusions (2 mL/kg/min) were performed via gastric catheter until rectal discharge became clear in WGI groups. Ileum and gallbladder samples were obtained for in vitro and biochemical studies without irrigation in CG and after irrigation with different WGI solutions. Isolated ileum and gallbladder preparations were suspended in organ baths for contractile responses of carbachol and CCK. Also, biochemical analysis of tissue CCK levels was performed in ileum and gallbladder samples. Results In PEG group, gallbladder and ileum CCK levels were significantly higher than CG (p < 0.05). Also, DNP irrigation caused increased CCK levels in gallbladder samples (p < 0.05). In lower carbachol concentrations, PEG group showed increased contraction responses in gallbladder samples when compared with controls (p < 0.05). However, ileal responses to carbachol did not show any significant difference between groups, contraction responses to CCK was decreased in PEG group when compared with CG (p < 0.05). Conclusion Among WGI solutions, PEG caused the highest CCK levels in gallbladder and ileum samples. Different WGI solutions affected the contractile responses of gallbladder and ileum smooth muscles divergently. Increased levels of CCK in PEG group support the decreased contractile responses in ileum. Therefore, our results confirm that the effect of WGI on gallbladder and ileum contractility may be CCK related.
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    Ultrastructural damage in vascular endothelium in rats treated with paclitaxel and doxorubicin
    (Taylor & Francis Inc, 2006) Yamaç, Deniz; Elmas, Çiğdem; Özoğul, Candan; Keskil, Zuhal; Dursun, Ayşe
    Endothelium is the first physiological barrier between blood and tissues and can be injured by physical or chemical stress, particularly by the drugs used in the cancer therapy. Paclitaxel and doxorubicin are frequently used anticancer drugs and their cardiac side effects are well observed in clinical setting. Their side effects on the endothelium are still not clear enough. There are few investigations assessing the damages elicited by the combination use of chemotherapy agents in animal experimental models. The purpose of this study was to examine and compare the side effects of doxorubicin and paclitaxel on endothelium in vivo. The drugs were administered weekly to rats via intraperitoneal injections singly or in combinations. Lastly, aorta endothelium was examined. The most familiar parts of the aorta endothelium are the nucleus, free ribosomes, Weibel-Palada granules, plasmalemmal vesicles, and clear basement membrane. Examination of the endothelium and the related structures revealed some clear degenerative findings. Notably, administration of a paclitaxel and doxorubicin combinations caused the most dramatic change in ultrastructure, which may disrupt many functions of the endothelium.