Aydogmus E. | Gul S. | Bahadir B.

Article | 2019 | World Neurosurgery122

Objective: We examined the protective effects of hesperidin on cerebral vasospasm by establishing an experimental rat model of subarachnoid hemorrhage and performing biochemical, pathologic, and histomorphometric analysis on these data. Methods: Forty albino Wistar rats were randomly divided into 5 groups of n = 8 in each: group (G)1, no experimental interventions; G2, subjected to subarachnoid hemorrhage; G3, subjected to subarachnoid hemorrhage and administered saline (100 mg/kg); G4, subjected to subarachnoid hemorrhage and treated with low-dose hesperidin (50 mg/kg); and G5, subjected to subarachnoid hemorrhage and treated with . . .high-dose hesperidin (100 mg/kg). Subarachnoid hemorrhage was created by injecting 0.15 cc of autologous blood taken from the rat-tail artery and injected into the cisterna magna from the craniocervical junction. Drugs were administered intraperitoneally as twice daily doses for 48 hours. Rats were euthanized at the end of this period. Results: No statistically significant decrease was observed in malondialdehyde levels, which is the end-product of lipid peroxidation, among the drug groups (G4 and G5). Thin sections prepared from the basilar artery were examined morphologically. Severe luminal narrowing and vessel-wall thickening were observed in the subarachnoid hemorrhage groups (G2, G3). In the hesperidin-administered groups (G4, G5), it was determined that vessel wall thickness measurements revealed thinner walls than in the subarachnoid hemorrhage groups (G2, G3) and the luminal diameters were significantly larger than in the subarachnoid hemorrhage groups (G2, G3). Conclusions: These findings suggest that hesperidin has no effect on malondialdehyde-associated lipid-peroxidation activity; however, it might be useful in subarachnoid hemorrhage therapy because of its beneficial effects on vessel wall thickness and luminal diameters. © 2018 Elsevier Inc Daha fazlası Daha az

Edebali N. | Tekin İ.Ö. | AçıkgÖz B. | AçıkgÖz Ş. | Barut F. | Sevinç N. | SümbüloĞlu V.

Article | 2014 | Neurological Research36 ( 12 ) , pp.1114 - 1120

Objectives: The circumventricular organs (CVOs) are essential for most autonomic and endocrine functions. Trauma and bleeding can affect their function. The aim of this study was to investigate apoptosis and necrosis in CVOs in the early period after experimental subarachnoid hemorrhage (SAH) in rats, using annexin V affinity and caspase 3 immunostaining.Methods: Three experimental groups were used: Days 1 and 2 after SAH, and a control group, seven Wistar albino rats each. Subarachnoid hemorrhage was accomplished by transclival basilar artery puncture. Rats were perfused with 0.9%NaCl and 0.1M phosphate buffer pH 7.4 until heart st . . .oppage. Apoptosis and necrosis in CVOs were measured by flow cytometry with annexin V staining, and by caspase 3 immunostaining.Results: Apoptosis in the organum vasculosum lamina terminalis (OVLT), median eminence (ME), and area postrema (AP) was significantly higher in the Day 1 group than in the control group. Apoptosis in the subfornicial organ (SFO), OVLT, ME, and AP was significantly higher in the Day 2 group than in the control group. There were significant differences between the Day 1 and Day 2 groups, except for AP. Necrosis in SFO and OVLT was significantly higher in the Day 2 group than in the Day 1 or control groups, whereas necrosis in the ME and AP did not differ between the three groups. Caspase 3-positive cell density was more intense in the Day 2 group than in the Day 1 and control groups.Discussion: Prevention of apoptosis may potentially improve impaired functions of CVOs after SAH. © W. S. Maney & Son Ltd 2014 Daha fazlası Daha az

Akpinar G. | Açikgöz B. | Sürücü S. | Çelik H.H. | Çagavi F.

Article | 2005 | Neurological Research27 ( 6 ) , pp.580 - 585

Objectives: Circumventricular organs (CVOs) are fine, periventricular, neurotransmitter-rich structures that are devoid of a Blood-brain barrier and are known for their secretory role controlling fluid and electrolyte balance, thirst and even reproduction. Common pathologies of the brain such as trauma or bleeding affect CVOs, and hence their function. However, at what stage of these disease processes are CVOs affected and the time sequence of their recovery is still not clear. The aim of this study was to detect the morphological changes in CVOs using electron microscopy after experimental subarachnoid hemorrhage (SAH). Methods: Ex . . .perimental SAH was induced by transclival puncture of the basilar artery. Both scanning and transmission electron microscopic examination of the representive sections from each CVO was undertaken. Results: Electron microscopy has shown that after SAH, the cells that form the CVOs exhibit signs of cellular necrosis with margination of the nucleus as well as cytoplasmic, mitochondrial and axonal edema. The subfornicial organ and organum vasculosum lamina terminalis appear to be more vulnerable to the effects of SAH than the median eminence or area postrema. Discussion: Considering the fact that the experimental SAH model we have used is very similar to the momentary rupture of an aneurysm with secondary reflex spasm to seal the hole, it will not be unrealistic to consider that similar effects may also take place in the clinical setting. © 2005 W. S. Maney & Son Ltd Daha fazlası Daha az

Gul S. | Bahadir B. | Hanci V. | Bektas S. | Can M. | Kalayci M. | Acikgoz S.

Article | 2010 | Journal of Clinical Neuroscience17 ( 8 ) , pp.1038 - 1041

We examined the effects of the phosphodiesterase 5 (PDE-5) inhibitor vardenafil on cerebral vasospasm in an experimental rat subarachnoid hemorrhage (SAH) model. Thirty-two albino Wistar rats were divided into five groups: G1, no experimental intervention; G2, administered subarachnoid physiological saline after sham surgery; G3, subjected to SAH; G4, subjected to SAH and administered low-dose (0.5 mg/kg) vardenafil treatment; and G5, subjected to SAH and administered high-dose (5 mg/kg) vardenafil treatment. For animals in G3, G4 and G5, SAH was induced by an injection of autologous non-heparinized blood into the cisterna magna. Im . . .mediately after SAH, for animals in G4 and G5, vardenafil was administered by gavage at intervals of 8 hours for 2 days. The rats were then decapitated, and basilar arteries and blood samples were taken for biochemical and histopathological examination. Malonyldialdehyde values in G2 (p = 0.004) and G3 (p = 0.002) were significantly higher than those in G1. G4 and G5 had significantly lower values than G2 and G3 (p = 0.014, G4 v. G2; p = 0.005, G4 v. G3; p = 0.005, G5 v. G2; p = 0.002, G5 v. G3). Total antioxidant capacity (TAC) values in G3 were significantly lower than those in G1 (p = 0.041). TAC values in G4 and G5 were significantly higher than those in G3 (p = 0.043). Mean luminal diameter in G3 was significantly smaller compared with G1 and G2 (p = 0.002), but larger in G4 (p = 0.002) and G5 (p = 0.001) compared with G3. Mean luminal diameter was also significantly larger in G5 than in G2 (p = 0.008) and G4 (p = 0.038). Mean wall thickness in G2 (p = 0.015) and G3 (p = 0.002) was significantly thicker compared with G1. Wall thickness was significantly thinner in G4 and G5 compared with G2 and G3 (p = 0.008, G4 v. G2; p = 0.001, G4 v. G3; p = 0.005, G5 v. G2; p = 0.001, G5 v. G3). Our results confirm that vardenafil may induce vasodilatation and provide potential benefits in SAH therapy by preventing vasospasm. © 2010 Elsevier Ltd. All rights reserved Daha fazlası Daha az

Gul S. | Bahadir B. | Hanci V. | Acikgoz S. | Bektas S. | Ugurbas E. | Ankarali H.

Article | 2010 | Journal of Clinical Neuroscience17 ( 5 ) , pp.608 - 611

We investigated the effect of ebselen relative to nimodipine in an animal model of subarachnoid hemorrhage. Thirty Wistar albino rats were divided into 5 groups: G1, no intervention; G2, sham surgery without subarachnoid hemorrhage (SAH); G3, SAH only; G4, SAH plus nimodipine treatment; G5, SAH plus ebselen treatment. For G2 animals, physiological saline (0.9% NaCl) was injected into the cisterna magna. For G3, G4 and G5 animals, SAH was induced by injecting autologous non-heparinized blood into the cisterna magna. One hour after injection, G4 animals received nimodipine at 6-hour intervals and G5 animals received ebselen twice a da . . .y for 48 hours. After treatment, brain tissue and blood samples were taken for biochemical and histopathological examination. Mean malonyldialdehyde concentration was significantly higher in G3 than in G1 (p < 0.0001), G2 (p = 0.01), G4 (p = 0.002) and G5 (p = 0.014), and significantly higher in G5 than in G1 (p = 0.013). Mean superoxide dismutase activity was significantly lower in G4 than in both G1 (p = 0.025) and G2 (p = 0.02). Mean wall thickness was significantly greater in G3 than in G1 (p < 0.0001), G2 (p = 0.01), G4 (p < 0.0001) and G5 (p < 0.0001). Mean wall thickness was also significantly greater in both G1 and G2 than in G4 (p < 0.0014 and p < 0.0001) and G5 (p < 0.0001 and p < 0.0001). Mean luminal diameter of the basilar artery was significantly smaller in G3 than in G2 (p = 0.02), G4 (p < 0.018) and G5 (p < 0.001). Our results confirm that ebselen may have neuroprotective effects by acting to prevent vasospasm. © 2009 Elsevier Ltd. All rights reserved Daha fazlası Daha az

Karatas A. | Gokce F. | Demir S. | Ankarali S.

Article | 2008 | Neuroscience Letters445 ( 1 ) , pp.58 - 61

The opium alkaloid papaverine (PPV) causes vasodilatation of the cerebral arteries through direct action on smooth muscle that reduces the constriction of smooth muscle. Intra-arterial papaverine (IAP) has been used widely to increase the regional cerebral blood flow in order to reverse the cerebral vasospasm that occurs during endovascular procedures. IAP-induced seizures have been reported, although PPV has anticonvulsive effects. This study determined the effects of IAP on electrocorticography (ECoG) in the ketamine anesthetized rats. We used 24 Sprague-Dawley male rats weighing 200-250 g. The animals were divided randomly into f . . .our groups: three treatment groups (groups 1-3) and a control (group 4). Groups 1, 2, and 3 were given 1, 7, and 14 mg/kg IAP, respectively. The ECoG was compared across groups. Our results indicated that IAP did not cause seizures and that it decreased the frequency of ketamine-induced epileptiform activity in the 14 mg/kg group. Crown Copyright © 2008 Daha fazlası Daha az