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Öğe Effects of dexmedetomidine and dexketoprofen on the conduction block of rat sciatic nerve(WOLTERS KLUWER MEDKNOW PUBLICATIONS, 2020) Taylan, Sengal Bagci.; Bariskaner, Hulagu.Dexmedetomidine is a selective alpha 2-adrenoceptor agonist that is used because of its sedative, anxiolytic, and analgesic effects. Dexketoprofen, which is used as an analgesic, is a nonselective nonsteroidal anti-inflammatory drug (NSAID). The use of dexmedetomidine and dexketoprofen as adjuvants to local anesthetics for the peripheral nerve is gradually increasing. In this study, we aimed to investigate the effects of different doses of dexmedetomidine and dexketoprofen on conduction block of rat sciatic nerve. The isolated sciatic nerve from adult rats was transferred to a nerve chamber. The compound action potentials (CAPs) were recorded from stimulated nerve with electrophysiological methods. Dexmedetomidine (n = 8) and dexketoprofen (n = 8) were administered in the chamber with cumulative concentrations of 10-9 to 10-5 M, and the CAPs were recorded for 5 and 10 minutes. The CAP parameters were calculated. Both dexmedetomidine and dexketoprofen significantly depressed all CAP parameters in a dose-dependent manner compared with the control group, i.e., the group in which rats did not receive treatment. CAP parameters showed there was no significant difference in nerve conduction inhibition between dexmedetomidine and dexketoprofen. Higher doses of dexmedetomidine suppressed the conduction in the fast-conducting fibers; however, dexketoprofen was found to suppress the conduction in the slow-conducting fibers in a time-dependent manner and suppress the conduction in the medium- and slow-conducting fibers in a dose-dependent manner. These findings suggest that dexmedetomidine and dexketoprofen exhibit better anesthetic effects on peripheral nerve through different ways of action. The experimental procedures were approved by the Necmettin Erbakan University on January 30, 2013 (approval No. 2013-024).Öğe The effects of dexmedetomidine on human internal mammary artery and saphenous vein grafts under hypothermia and normothermia(COMENIUS UNIV, 2019) Oc, B.; Arun, O.; Taylan, S. B.; Oc, M.; Bariskaner, H.; Duman, A.OBJECTIVES: The purpose of this study was to determine the effects of hypothermia and normothermia on the isolated human saphenous vein (SV) and internal mammary artery (IMA) responses to dexmedetomidine. METHODS: The response of human IMA and SV strips with (E+) and without (E-) endothelium subjected to cumulative concentrations of (10(-9), 0(-6) M) dexmedetomidine were recorded at 37 degrees C and at 28 degrees C. OnE-way ANOVA was used for analysis. A p < 0.05 was considered significant. RESULTS: At 37 degrees C dexmedetomidine resulted in similar signifi cant concentration-dependent contractions in both E+ and E-SV strips (p < 0.05). At 37 degrees C dexmedetomidine resulted in signifi cant concentration-dependent contractions in E+ IMA strips, these contractions were significantly lower at all concentrations of dexmedetomidine in E-compared to E+ IMA strips (p < 0.05). When results between similar groups of SV and IMA strips were compared, the contractions were significantly higher in the IMA strips in E+ and E-at 37 degrees C and also E-28 degrees C groups compared to SV (p < 0.05). CONCLUSION: In conclusion, dexmedetomidine causes in vitro vasoconstriction in human IMA and SV grafts. These contractions are greater in IMA compared to SV grafts. Endothelium-derived pathways are possibly involved in the contractile responses of IMA. Moderate hypothermia augments vasoconstriction in SV graftsÖğe In vitro vasoactive effects of dexmedetomidine on isolated human umbilical arteries(COMENIUS UNIV, 2019) Arun, O.; Taylan, S. B.; Duman, I; Oc, B.; Yilmaz, S. A.; Tekin, A.; Celik, C.; Bariskaner H.; Celik J. B.OBJECTIVE: We aimed to investigate the vasoactive effects of dexmedetomidine on isolated human umbilical arteries and possible mechanisms involved. METHODS: Human umbilical artery strips were suspended in Krebs-Henseleit solution and dose-response curves were obtained for cumulative dexmedetomidine before and after incubation with different agents; propranolol, atropine, yohimbine, prazosin, indomethacin, verapamil. Effects of calcium on cumulative dexmedetomidine-induced contractions were also studied. RESULTS: Cumulative dexmedetomidine resulted in dose dependent contraction responses. Incubation with propranolol (Emax: 93.3 +/- 3.26 %), atropine (Emax: 92.0 +/- 6.54 %), or indomethacin (Emax: 94.25 +/- 2.62 %), did not attenuate dexmedetomidine-elicited contractions (p > 0.05). There were significant decreases in the contraction responses of cumulative dexmedetomidine with yohimbine (Emax: 12.1 +/- 11.9 %), prazosin (Emax: 28.8 +/- 4.6 %) and verapamil (Emax: 11.2 +/- 13.6 %) (p < 0.05). In Ca+2 free medium contraction responses to cumulative dexmedetomidine was insignificant (Emax: 5.20 +/- 3.42 %). Addition of cumulative calcium to the Ca+2 free medium resulted in concentration dependent increase in contractions (Emax: 64.83 +/- 37.7 %) (p < 0.05). CONCLUSION: Dexmedetomidine induces vasoconstriction in endothelial-free umbilical arteries via both, alpha(1)- and alpha(2)-adrenergic receptors and also extracellular Ca+2 concentrations play a major role. beta-adrenergic receptors, muscarinic cholinergic receptors, and inhibition of cyclooxygenase enzyme are not involved in this vasoconstriction (Fig. 3, Ref. 36). Text in PDF www.elis.sk.Öğe Effect of ethyl acetate extract of usnea longissima on esophagogastric adenocarcinoma in rats(ACTA CIRURGICA BRASILEIRA, 2019) Mammadov, Renad; Süleyman, Bahadır; Altuner, Durdu; Demirci, Elif; Çetin, Nihal; Yılmaz, Adnan; Baykal, Hüseyin; Alpcan, Hilal; Turumtay, Emine Akyüz; Süleyman, HalisPurpose: To investigate the effects of the EtOAc extract of U. longissima which is uninvestigated previously on esophagogastric cancer induced in rats with N-methyl-N-nitro-N-nitrosoguanidin (MNNG). Methods: The anticancer activity of EtOAc extract of U. longissima was examined in the esophagogastric adenocarcinoma models induced in rats with MNNG. EtOAc extract of U. longissima, 50 and 100 mg/kg oral doses were administered once daily for six months. MNNG induced differentiated and undifferentiated type adenocarcinomas in the esophageal and gastric tissues of rats. Results: EtOAc extract of U. longissima obtained from U. longissima prevented gastric and esophageal cancerogenesis induced in rats with MNNG. EtOAc extract of U. longissima did not have a lethal effect at doses of 500, 1000 and 2000 mg/kg. The prominent anticarcinogenic activity of EtOAc extract of U. longissima 50 and 100 mg/kg suggests that it is not toxic and it is selective to the cancer tissue. Conclusion: This information may shed light on clinical implementation of EtOAc extract of U. longissima in future.Öğe Alterations in hepatic gene expressions of CYP2C11, CYP2C6V, and CYP2D3 enzymes in endotoxemic rats(AVES, 2017) Ozer, Erdem K.; Kurtgoz, Serkan; Goktas, Mustafa T.; Karaca, Ragip O.; Caliskan, Metin; Bariskaner, Hulagu; Iskit, Alper B.Objective: Human cytochrome P450 2C9 (CYP2C9), CYP2C19, and CYP2D6 (corresponding to rat CYP2C11, CYP2C6V, and CYP2D3, respectively) are the major enzymes responsible for the metabolism of a wide range of drugs and chemicals. Changes in CYP efficiency are associated with disease susceptibility that can lead to drug toxicity or ineffective therapy. We aimed to examine the effects of lipopolysaccharide (LPS)-induced endotoxemia on gene expressions of hepatic microsomal CYP enzymes in rats. Material and Methods: Male Wistar albino rats were allocated into two subgroups of control and LPS. Saline or LPS (10 mg/kg) of same volume (1 mL/kg) was intraperitoneally (i.p.) injected into rats. After 4 hours, liver tissues were removed. Hepatic mRNA expressions of the CYP enzymes were quantitatively analyzed using real-time polymerase chain reaction (PCR). Results: Hepatic gene expressions of CYP2C11 and CYP2C6V decreased (3.35 and 2.25 fold, respectively) in the endotoxemic rats; however, CYP2D3 expression did not change. Conclusion: Our results revealed that endotoxemia changes CYP2C11-and CYP-2C6V-mediated-drug metabolism. Therefore, drug dosage must be cautiously adjusted in the patients with endotoxemia and sepsis.Öğe Levobupivakainin ve ropivakainin izole insan umblikal arter ve veni üzerine in vitro vazoaktif etkileri(AVES YAYINCILIK, 2011) Kılıçaslan, Alper; Duman, Ateş; Şahin, Ayşe SaideAmaç: Levobupivakain ve ropivakainin endotelli ve endotelsiz insan umblikal arteri ve umblikal veni üzerindeki in vitro vazoaktif etkilerinin araştırılması amaçlanmıştır. Gereç ve Yöntemler: Damar şeritleri, kasılma cevapları izometrik olarak poligrafa yazdırılmak üzere 37°C’de oksijen içinde %5 CO2 karışımı ile sürekli olarak gazlandırılan organ banyosu içine yerleştirildi. Endotelin etkisini değerlendirmek amacıyla dokuların bir bölümünün endotelleri mekanik olarak sıyrıldı. Seratonin (10-6 M 5-HT, n=7) ile önceden kasılma sağlandı. Maksimum kasılma cevapları elde edildikten sonra dokular yıkanarak dinlendirildi. Kümülatif tarzda levobupivakain (10-9-10-4 M; n=7) ve ropivakain (10-9-10-4 M; n=7) ilave edilerek konsantrasyon-cevap eğrileri elde edildi. Kasılma cevapları 5-HT ile alınan maksimum kasılma cevabının yüzdesi (%) şeklinde değerlendirildi. Bulgular: Levobupivakain ve ropivakainin umblikal arter ve ven düz kasında konsantrasyon bağımlı kontraksiyon meydana getirdikleri gözlemlendi. Levobupivakain ile maksimum kasılma (Emax) cevapları hem umblikal arter (79.2±2.5) hemde umblikal vende (71.1±2.6) ropivakaine göre (68.4±2 ve 36.2±2.8) anlamlı olarak daha yüksekti. Ajanların Emax cevapları umblikal vene göre umblikal arterde anlamlı olarak daha yüksekti . Endotelli ve endotelsiz dokular arasındaki kasılma cevaplarında istatistiksel olarak anlamlı fark belirlenmedi. Sonuç: Yüksek doz levobupivakain ve ropivakain, umblikal damarlarda gelişebilecek kontraksiyona bağlı olarak fetal kan akımını azaltabileceği sonucuna varılabilir.Öğe Diabetes mellitus-and cooling-induced bladder contraction: An in vitro study(2010) Atalik K.E.; Okudan N.; Gokbel H.; Kalkan S.; Cuce G.The effects of diabetes mellitus during cooling on ACh-and KCl-induced responses were investigated in rat urinary bladder. Diabetes was induced in the rats by 50 mg/kg streptozotocin via an intraperitoneal injection. Rats' body and bladder weights were measured. The isometric tension to ACh (10-9 -3 × 10-4 M) and KCl (5-100 mM) in strips of urinary detrusor muscle of diabetic and non-diabetic rats, in organ baths at 37 and 28°C were recorded. The body weights were significantly decreased and the bladder weights increased in STZ-induced diabetic group compared to the non-diabetic group. ACh and KCl caused concentration-dependent contractions of urinary bladders from non-diabetic and STZ-induced diabetic rats. During cooling, the sensitivity and the maximal response were significantly higher than those during 37°C, both in non-diabetic and diabetic preparations. Cooling of detrusor muscle preparations induces a graded contraction inversely proportional to the temperature in diabetic rats. It may be assumed that the cooling response involves the same mechanisms in the diabetic and non-diabetic animals.Öğe The Correlation of Nitrous Oxide of nNOS and p53 During Developing Brain(EDIZIONI MINERVA MEDICA, 2010) Barışkaner, H.; Tosun, M.[Abstract not Available]Öğe Response to Vasoconstrictor Agents by Detrusor Smooth Muscles From Cisplatin-Treated Rats and Antioxidant Treatment(Prous Science, Sa-thomson Reuters, 2010) Atalık, Kısmet Esra; Keleş, Bahar; Uyar, Yavuz; Dündar, M. A.; Öz, M.; Esen, H. H.The effects of melatonin and quercetin on the contractile responses of cisplatin-treated rat detrusor smooth muscle were tested. Detrusor strips obtained from four separate rat groups (control, cisplatin, melatonin+cisplatin and quercetin+cisplatin) were mounted in 25 mL organ baths containing Krebs-Henseleit solution (KHS) at 37 degrees C, continuously gassed with 95% O(2) and 5% CO(2). The vasoconstriction induced by acetylcholine (ACh) and potassium chloride (KCl) were compared within the groups. Furthermore, histopathological parameters such as edema, congestion, inflammatory cells, microvascular proliferation, fibrosis, eosinophil, most cells and epithelial damage were noted. In routine experiments ACh and KCl triggered concentration-dependent contractions. Pretreatment with cisplatin increased the sensitivity but not the maximal response to ACh and KCl. In rats treated with melatonin or quercetin before cisplatin, the EC(50) values, but not the maximal response, to both agents were significantly higher than in the cisplatin-treated (CII) group. Histopathological parameters such as edema, congestion, inflammatory cells, microvascular proliferation, fibrosis, eosinophil, most cells and epithelial damage were all higher in the cisplatin-treated group than in the controls. Melatonin pretreatment significantly decreased mast cell numbers and epithelial damage when compared to cisplatin treatment alone but these effects were not recorded with quercetin pretreatment. These results demonstrate for the first time that melatonin can attenuate urinary bladder injury produced by cisplatin treatment.Öğe Effect of Lycopene on Caspase-3 Enzyme Activation in Liver of Methanol-Intoxicated Rats: Comparison with Fomepizole(MARY ANN LIEBERT INC, 2010) Kurçer, Mehmet Ali; Kurçer, Zehra; Köksal, Mete; Baba, Füsun; Ocak, Ali Rıza; Aksoy, Nurten; Ateşşahin, Ahmet; Sahna, EnginLycopene is one of the major carotenoids and is found almost exclusively in tomatoes and tomato products. This study was performed to evaluate the effect of lycopene on methanol-induced liver injury and to compare the results with those after fomepizole, which is used in treatment of methanol intoxication. Experiments were carried out with 30 female Wistar rats weighting 180-200 g. Rats were injected with a intraperitoneally dose of 3 g/kg methanol as a 50% solution in isotonic saline once for intoxication. Rats were pretreated with fomepizole (50 mg/kg) and/or lycopene (10 mg/kg) before methanol. After 24 hours all the drug-treated and intoxicated rats were sacrificed under anesthesia. Malondialdehyde (MDA) levels were determined in order to assess lipid peroxidation, and caspase-3 activity was determined by immunostaining of liver tissues to evaluate apoptosis. Methanol administration significantly increased the MDA level and caspase-3 activity in liver. Pretreatment with lycopene and/or fomepizole decreased the MDA levels significantly. Similarly, lycopene and fomepizole decreased methanol-induced caspase-3 activity. The findings of the present study demonstrate that methanol intoxication causes hepatic toxicity in rats and that this is likely a result of reactive oxygen species and apoptosis induction. Lycopene has protective effects against methanol-induced hepatic injury similar to fomepizole. It was demonstrated for the first time that both lycopene and fomepizole prevent methanol-induced hepatic injury by reducing the increase of lipid oxidation and caspase-3 activation.Öğe Combination Antioxidant Effect of Alpha-tocoferol and Erdosteine in Ischemia-Reperfusion Injury in Rat Model(Springer, 2010) Yurdakul, Talat; Kulaksızoğlu, Haluk; Pişkin, Mehmet Mesut; Avunduk, Mustafa Cihat; Ertemli, Esra; Gökçe, Gürhan; Barışkaner, Hulagü; Büyükbaş, Sadık; Kocabaş, Volkan[Abstract not Available]Öğe Combination Antioxidant Effect of Alpha-Tocoferol and Erdosteine in Ischemia-Reperfusion Injury in Rat Model(Springer, 2010) Yurdakul, Talat; Kulaksızoğlu, Haluk; Pişkin, Mehmet Mesut; Avunduk, Mustafa Cihat; Ertemli, Esra; Barışkaner, Hulagü; Büyükbaş, Sadık; Kocabaş, VolkanIntroduction Renal ischemia/reperfusion (I/R) which is an important cause of renal dysfunction is inevitable in renal transplantation, surgical revascularization of the renal artery, partial nephrectomy and treatment of suprarenal aortic aneurysms. Aim The purpose of this study was to investigate the efficacy of alpha-tocopherol and erdosteine combination in the reduction in injury induced by ROS in a rat model of renal ischemia-reperfusion. Materials and methods Thirty-six-male Wistar albino rats weighing 200-250 g were utilized for this study. Rats were divided into six groups, and each group was consistent of six rats: (1) sham-operated (control), (2) ischemia group (3) I/R group, (4) I/R/alpha-tocoferol group (5) I/erdosteine group (6). I/R/alpha-tocoferol and erdosteine group. Biochemically tissue MDA, XO and SOD activities, light and electron microscopic findings were evaluated. Results The erdosteine and alpha-tocoferol significantly reversed the effect of protein oxidation and lipid peroxidation induced by I/R shown by the decreased levels of MDA and XO activities. Both MDA and XO levels were found to be lower in group 6 compared to single agent treatment groups, and this was significantly different. All treatment groups showed increased SOD activity, which accounts for their oxidative properties. The mean Paller score of the combination treatment group (group 6) was lower than all groups except the sham group (3.67 +/- 1.2), and this finding was statistically significant (0.05). Our results showed that the antioxidant pretreatment with alpha-tocopherol and erdosteine combination reduced lipid peroxidation of renal cellular membranes in a model of normothermic renal ischemia-reperfusion in rats. Combination of erdosteine and alpha-tocopherol has a synergistic effect of protection against oxidative processes. Long-term use of alpha-tocopherol seems to have a greater effect on the prevention of IR injury. However, further investigations are needed for the clinical applications of our findings.Öğe Beneficial Effects of Levosimendan on Cerebral Vasospasm Induced by Subarachnoid Haemorrhage: An Experimental Study(Taylor & Francis Ltd, 2010) Cengiz, Şahika Liva; Erdi, Mehmet Fatih; Tosun, Murat; Atalık, Esra; Avunduk, Mustafa Cihat; Sönmez, Fatma Cavide; Mehmetoğlu, İdris; Baysefer, AlperBackground: The aim of this study was to investigate the ability of levosimendan to prevent cerebral vasospasm in a rabbit model of subarachnoid haemorrhage (SAH). Animals and methods: Eighteen New Zealand white rabbits were allocated into three groups randomly. SAH was induced by injecting autologous blood into the cisterna magna. (Group 1 = control: sham surgery group, Group 2 = SAH alone group, Group 3 = SAH plus levosimendan group). Histopathological examination was performed on day 3 as described. Intravenous levosimendan dose (initially 12 mu g kg(-1) infusion, continuously for at least 10 minutes and then continued with a dose of 0.2 mu g kg(-1) min(-1)) treatment was started after the induction of SAH. Three days later, the animals were sacrificed. Results: In pathological investigation; there was statistically significant difference in luminal area and muscular wall thickness of the basilar artery between all groups (p < 0.005). Malondialdehyde level was also found significantly low in the levosimendan group compared with the SAH group. Conclusion: Intravenous levosimendan treatment was found effective by increasing the pathological luminal area and reducing muscular wall thickness measurements. This is the first study to show that intravenous administration of levosimendan is effective in preventing cerebral vasospasm induced by SAH in rabbits.Öğe The Mechanisms of the Direct Vascular Effects of Sevoflurane on Saphenous Veins in Vitro(2009) Ölçer, Havva Feyza; Erol, Atilla; Şahin, Ayşe S.; Otelcioğlu, ŞerefAim: The purpose of this study was to determine the mechanism of the directs effects of sevoflurane on human veins in vitro. Methods: Dose-response curves were obtained for cumulative doses of sevoflurane(0.5, 1, 1.5 and 2 MAC) on saphenous vein strips precontracted with 5-hydroxytryptamine( 5-HT 10 -6 mol/L) incubated with either Nco-nitroL-arginine-methyl ester(L-NAME)(10-4 mol/L), indomethacine(10-5 mol/L), glibenclamide(10-6 mol/L) or tetraethylammonium(10-4 mol/L) Results: Preincubation of vein strips with tetraethylammonium(TEA, Ca++-activated K+ channel blocker) did not influence the relaxant responses to sevoflurane(p>0.05). L-NAME, indomethacine and glibenclamide reduced the relaxation response to sevoflurane(p<0.05). Conclusion: Our results demonstrated that sevoflurane produces concentration dependent relaxation in human saphenous vein. The relaxant effects of sevoflurane are probably related with activation of nitric oxide synthase, cyclooxygenase and KATP channels pathways.Öğe Cooling and Response to Histamine in Calf Cardiac Vein(2009) Atalik, K. E.; Kılıç, M.In the present work we studied the responses of calf cardiac vein to histamine (10-9-3x10-4M) and effects of moderate cooling (to 28 °C) on these responses with analysis of the role of endothelial mediators and K+ -ions. Concentration-response curves to histamine were isometrically recorded at 37 and 28 °C (control). The same procedure was repeated at 28°C in the presence of NG-nitro-L-arginine methyl ester (L-NAME, 10-4 M), indomethacin (10-5 M), and also in the K+-free medium. During cooling, the sensitivity, but not the maximal response, was significantly lower than 37 °C. Cooling to 28°C after treatment with L-NAME did not modify the effect of cooling, whereas treatment with indomethacin increased, significantly. Furthermore, cooling to 28 C after incubation in K+-free solution increased the sensitivity to histamine. The results of this study suggest the role of cyclooxygenase pathway and also K+ ions in the cooling-induced changes of calf cardiac vein treated with histamine.Öğe Effect of Cooling on the Responses of Human Saphenous Vein to Fentanyl, Remifentanil and Sufentanil(Blackwell Publishing, 2006) Şahin, Ayşe Saide; Duman, Ateş; Günaydın, İshak Gürsel; Şahin, Tahir Kemal; Görmüş, Niyazi; Duman, İpekWe studied the vasodilatory effects of fentanyl, remifentanil and sufentanil on the human saphenous vein strips at 37, 32 and 28 degrees C. Fentanyl produced concentration-dependent relaxation of human saphenous vein strips precontracted with 5-hydroxytryptamine (5-HT) at every temperature studied. Compared with vein strips at 37 degrees C, relaxant responses to each one concentration of fentanyl were significantly reduced at 32 and 28 degrees C. Remifentanil relaxed vein strips in a concentration-dependent way and the relaxation for all concentrations were significantly greater at 32 and 28 degrees C compared with 37 degrees C. Sufentanil produced concentration-dependent relaxation in saphenous vein strips precontracted with 5-HT. These relaxant responses were similar at 32 degrees C compared with 37 degrees C. When bath temperature was lowered from 37 to 28 degrees C, the relaxant responses to sufentanil were significantly reduced. In summary, the present study suggests that cooling reduces the relaxation caused by fentanyl and sufentanil on human saphenous veins but augments the relaxation with remifentanil. The augmented vasodilatory effect of remifentanil with cooling may be useful on systemic vascular resistance and organ preservation under hypothermic conditions like cardiopulmonary bypass surgery.Öğe Effect of Deferoxamine on Na(+)K(+)ATPase Activity After Cerebral Ischemia in Rabbits(Riyadh Armed Forces Hospital, 2006) Gürbilek, Mehmet; Topçu, Cemile; Aköz, Mehmet; Barışkaner, Hülagü; Üstün, Mehmet E.; Köylü, ÖznurObjective: To study the effects of deferoxamine on tissue sodium-potassium adenosine triphosphatase (Na+-K+ ATPase) activity on cerebral ischemia in rabbits. Methods: We cared for the animals in the Pharmacology Department of the Medical School of Selcuk University in 2004. We used 30, New Zealand, 7-day-old male rabbits in the experiment. We anesthetized all the animals with xylazine hydrochloric acid and ketamine. We divided the rabbits equally into 3 groups. In group 1 (n=10) (sham group), we observed baseline levels, and did not apply ischemia. In group 2 (n=10) (untreated group) we produced cerebral ischemia by clamping the bilateral common carotid arteries for 60 minutes, and in group 3 (n=10), we administered deferoxamine (DFO) 50 mg/kg intravenously immediately after opening the clamps. Results: The Na+-K(+)ATPase activity increased after DFO treatment (p=0.045). Conclusion: We conclude that Na+-K(+)ATPase activity in cortical brain tissue was higher in DFO-treated rabbits compared with untreated animals after ischemia.Öğe Sufentanil ve Remifentanilin İzole Perfüze Rat Böbreği Üzerine Etkileri(2004) Barışkaner, H.; Tuncer, Sema; Otelcioğlu, Ş.; Doğan, N.; Yosunkaya, A.; Kılıç, M.In this in vitro study on isolated perfused rat kidney, the effects of indomethacin, NG-nitro-L arginin methyl ester (L-NAME), propranolol, naloxone, glibenclamide and tetraethylammonium (TEA) on the responses induced by fentanyl, sufentaniyl and remifentanil were investigated. In isolated perfused rat kidney, under a constant flow of 8-10 ml/min, mean basal perfusion pressure and the responses of used inhibitors or antagonists were recorded on a polygraph. Fentanyl (10-9-10-6 M), sufentanil (10 -9-10-6 M) and remifentanil (10-9-10 -6 M) caused a dose-dependent decrease in perfusion pressure raised by submaximum concentration of phenylephrine. Fentanyl induced relaxations were inhibited by glibenclamide (10-5 M, n = 5) and TEA (10-3 M, n = 5) (p < 0.05) but not indomethacin (10-5 M, n = 5), L-NAME (10-4 M, n = 5), propranolol (10-6 M, n = 5) and naloxone (10-6 M, n = 5) (p > 0.05). Both sufentanil- and remifentalin-induced relaxations were not inhibited by indomethacin (10 -5 M, n = 5), L-NAME (10-4 M, n = 5), propranolol (10 -6 M, n = 5), naloxone (10-6 M, n = 5) (p > 0.05) and glibenclamide (10-5 M, n = 5) but TEA (10-3 M, n = 5) was effective (p < 0.05). These results suggest that in isolated perfused rat kidney, K+ channels may play a role in fentanyl-, sufentanil- and remifentanil-induced relaxation by opening ATP sensitive-potassium channels and calcium-activated potassium channels.Öğe Effect of Gabapentin on Postoperative Pain: A Randomized, Placebo-controlled Clinical Study(2005) Tuncer, Sema; Bariskaner, Hulagu; Reisli, Ruhiye; Şarkılar, Gamze; Çiçekçi, Faruk; Otelcioğlu, ŞerefBackground: Both clinical and experimental studies suggest that gabapentin (GBP) has analgesic effects in neuropathic pain. The aim of the study was to investigate the effect of gabapentin on postoperative pain. Methods: This study was performed on 45 (ASA I-II) patients planned for major orthopaedic surgery. 45 patients were randomized into three equal groups. Patients received 1200 mg GBP (Group I), 800 mg GBP (Group II) or placebo (Group III) 1 h before surgery. Anaesthesia was standardized for all patients. Morphine by intravenous patient-controlled analgesia was applied as 1 mg bolus dose and 7 min lockout time for postoperative analgesia. The pain was evaluated at the first 2 and 4 h after operation. The amount of morphine used was recorded at the same hours. Results: In all groups, there were no significant differences in the demographic characteristics, duration of surgery and anaesthesia, or dose of fentanyl received in the operating room. Pain scores and side effects were similar in all groups. Morphine consumption was lower in the Groups I and II than in the Group III at 2 h and 4 h postoperatively (p < 0.05). Morphine consumption was lower in the Group I than in the Group II at 2 h and 4 h (p < 0.05). Conclusion: Our results demonstrate that a single dose of 1200 or 800 mg oral gabapentin reduces morphine consumption in the early postoperative period. However, gabapentin 1200 mg is more effective than gabapentin 800 mg for pre-emptive analgesic effect.Öğe Warming and Response to Contractile Agents in Calf Cardiac Vein: Role of the Nitric Oxide(BLACKWELL PUBLISHING LTD, 2003) Atalik, Kısmet Esra; Sahin, AS; Ulusoy, HB; Dogan, NThe effects of warming on the response to various contractile agents of calf cardiac vein were studied using 2.5-mm long cylindrical segments. Concentration-response curves for carbachol (10(-9)-3 x 10(-4) M), 5-hydroxytryptamine (5-HT; 10(-8)-3 x 10(-3)), potassium chloride (KCl; 10(-4)-5 x 10(-2) m) and calcium chloride (CaCl2; 10(-4)-10(-2)) were isometrically recorded at 37 and 41degreesC (warming). During warming the sensitivity, but not the maximal response, of carbachol 5-HT, KCl, and CaCl2 was significantly higher than at 37degreesC. Warming to 41degreesC after treatment with N-G-nitro-L arginine methyl esther (10(-5) m) did not modify the effect of warming. These results suggest that nitric oxide seems to have no role in the warming-induced responses in calf cardiac vein.
