Biomedical subjects

Piraye Yargicoglu

Publications and source records attributed to Piraye Yargicoglu.

8 recordsLinked to original sources

PubMed2006

The effect of sulfur dioxide inhalation on active avoidance learning, antioxidant status and lipid peroxidation during aging.

The effect of SO2 was examined on active avoidance learning, thiobarbituric acid reactive substances (TBARS), and the activities of Cu, Zn superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) in young (3 months), middle-age (12 months ), and old (24 months) Swiss male albino rats. Ten ppm SO2 was administered to the animals of SO2 groups in an exposure chamber for 1 h/day x 7 days/week x 6 weeks while control groups were exposed to filtered air in the same condition. The most prominent effect of aging on active performance was also observed in the older group. SO2 exposure significantly decreased the active avoidance learning in the young group, but it had no effect on this parameter in the middle-aged and the older group compared with their corresponding control groups. SO2 exposure resulted in increased levels of Cu, Zn-SOD activity while decreased level of GSH-Px activity in all experimental groups compared with their corresponding control groups. CAT activities were unaltered. TBARS levels of all SO2 exposed groups were significantly increased compared with their respective control groups. In conclusion, results from the present research showed that SO2 exposure resulted in an increase in the lipid peroxidation and caused alterations in antioxidant enzyme activities. Additionally, SO2 exposure impaired cognitive function only in the young rats during the acquisition phase of active avoidance learning.

Administration, Inhalation↗

PubMed2006

The role of docosahexaenoic acid on visual evoked potentials in one kidney-one clip hypertension.

PURPOSE: To investigate the effects of polyunsaturated fatty acid (PUFA) docosahexaenoic acid (DHA) on visual evoked potentials (VEPs) in a one kidney-one clip (1K-1C) hypertension model in rats. METHODS: Five experimental groups were formed: a control group, a sham group, a group supplemented with DHA, a 1K-1C group, and a 1K-1C + DHA group. The DHA groups were treated for 60 days. In the 1K-1C groups, the right kidney was removed and a silver clip with a 0.2-mm gap was placed on the left renal artery. RESULTS: The DHA-supplemented rats had lower blood pressure than their respective controls (p < 0.01). The increased brain and retina thiobarbituric acid reactive substances (TBARS) levels in hypertensive rats were abolished by DHA administration. The brain nitrite levels were lower in the DHA, 1K-1C and 1K-1C + DHA groups compared with the control group (p < 0.01), and the retina nitrite level was higher in the 1K-1C + DHA group compared with the DHA and 1K-1C groups (p < 0.01). There was an improvement of P(2), N(2) and P(3) components following DHA supplementation in 1K-1C hypertensive rats compared with the 1K-1C group. CONCLUSION: The present study suggests that DHA supplementation has the potential to prevent VEP changes caused by an experimental model of hypertension. This state might be related to the lipid peroxidation lowering effect of DHA.

Animals↗

PubMed2005

The effect of chronic restraint stress and sulfite on visual evoked potentials (VEPs): relation to lipid peroxidation.

Stress and sulfite can stimulate numerous pathways leading to an increased production of free radicals which generate a peroxidation cascade producing lipid peroxidation, protein oxidation, DNA damage and cell death, and contribute to the occurrence of pathologic conditions. The purpose of our study was to investigate the effects of stress and sulfite on visual evoked potentials (VEPs) and to examine the relationship between lipid peroxidation and VEP changes. Forty male wistar rats, aged three months were used. They were equally divided into four groups: control (C), the group exposed to restraint stress (R), the group treated with sulfite (S) and the group exposed to stress and treated with sulfite (RS). Chronic restraint stress was applied for 21 days (1h/day) and sodium metabisulfite (520 mg/kg/day) was given by gavage for the same period. All latencies of VEP components were prolonged in the R, S and RS groups with respect to the C group. Brain and retina TBARS levels were found to be increased in those groups compared to the C group. Our results strongly suggest that the latency prolongations of all VEP components may have resulted from the enhancement of lipid peroxidation. Correlation analysis between brain and retina TBARS levels and VEP latencies also support this conclusion. Our data in regard to latency prolongations of all VEP components in the stress group exposed to sulfite, reflected an additive effect of sulfite toxicity on VEP components. Therefore it could be suggested that chronic exposure to stress and sulfite together is associated with a considerable health risk.

Animals↗

PubMed2003

The effect of different hypertension models on active avoidance learning.

This study tested the effects of different hypertension models on active avoidance learning in rats. Three-month-old male Wistar rats were divided randomly into six groups as follows: control (C), sham operated (sham), two kidney-one clip (2K-1C), one kidney-one clip (1K-1C), deoxycorticosterone-salt (DOCA), and N-omega-nitro-L-arginine-methyl ester (L-NAME) groups. Mean arterial blood pressures were significantly higher in four hypertensive groups compared with control and sham groups. The active avoidance training results indicated that hypertension state is associated with learning impairment. Thiobarbituric acid-reactive substances (TBARS) were determined as an indicator of lipid peroxidation in brain and hippocampus. Additionally, brain and hippocampus nitrite levels were studied.

Animals↗

PubMed2003

Fiber structure of optic nerve in cadmium-exposed diabetic rats: an ultrastructural study.

This study aimed to show ultrastructural effects of diabetes and cadmium on the optic nerve. We used 52 healthy Swiss albino male rats. They were divided into four groups: control (C), diabetic (D), cadmium, (Cd), and diabetic with cadmium (D + Cd). The diabetic condition was created by intravenous injection of 5 mg alloxan/100 g. Intraperitoneal CdCl2(2 mg kg/week) was given to Cd and D + Cd groups for two months. At the end of the experimental period, animals were sacrificed and the optic nerves were dissected at the front level of chiasma opticum. The tissue samples were investigated by using light and electron microscopic techniques. It was found that both diabetes and Cd intoxication cause myelin disorganization and organelle destruction in axoplasm and cytoplasm of glia. The results suggested that Cd increases the oxidative stress induced by diabetes, by disturbing some enzymatic mechanisms.

Animals↗

PubMed2003

Effect of immobilization and cold stress on visual evoked potentials.

The main aim of our research was to study the effects of immobilization and/or cold stress on amplitudes and latencies of visual evoked potentials (VEPs) and thiobarbituric acid reactive substances (TBARS). Forty healthy male albino rats, aged three months, were used. The rats were equally divided into four groups: Control group (C), the group exposed to cold stress (CS), the group exposed to immobilization stress (IS), and the group exposed to both cold and immobilization stress (CIS). Plasma corticosterone concentrations were significantly increased in all stress groups. Lipid peroxidation was increased in brain and retina of all stress groups as indicated by the significant increase in TBARS levels compared to the C group. Glutathione peroxidase (GSH-Px) activity in brain and retina increased in the CS group, but decreased in the IS group relative to the C group. GSH-Px activity also increased in the brain, but not in the retina in the CIS group with respect to the C group. The mean latencies of P1, N1, P2, N2, and P3 components were significantly prolonged in all stress groups compared with the C group. The results suggest that stress induced lipid peroxidation may influence VEPs.

Animals↗

PubMed2002

Effect of cadmium on sciatic nerve in diabetic rats: an ultrastructural study.

The present study demonstrated the ultrastructural effects of diabetes and cadmium on the peripheral nervous system. In this study we used 52 healthy Swiss male albino rats. They were divided into four groups: control (C), diabetic (D), cadmium (Cd), and diabetic and cadmium (D + Cd). The diabetic condition was induced by intravenous injection of 5 mg alloxan/100 g body weight, via the caudal vein. Cd and D + Cd groups were injected with CdCl2 intraperitoneally (2 mg/Kg/week) for two months. At the end of the experimental period, animals were sacrificed and their sciatic nerves were dissected. The tissue samples were investigated by using light and electron microscopic techniques. Upon investigation, it was seen that myelinated axons in sciatic nerve of diabetic and Cd treatment groups had onion-bulb type myelin destruction, melting, and protrusion. Basal lamina of capillary endothelia of D, Cd, and D + Cd groups were thickened and the endothelial apical membrane was rough. In conclusion, Cd toxicity exacerbated the destructive effect of diabetes on the peripheral nervous system.

Animals↗

PubMed2002

The effect of different hypertension models on visual evoked potentials.

Even though there is an abundance of information about the complications of hypertension, studies of its influence on visual evoked potentials (VEPs) are rare. In previous studies, it was pointed out that hypertension induces changes on VEPs. However, it has not yet been clarified which models of hypertension are more effective on VEPs. The aim of this study was to investigate this subject in rats. Animals were divided equally into six groups: control group (C), sham operated (Sham), two kidney-one clip (2K-1C), one kidney-one clip (1K-1C), deoxycorticosterone-salt (DOCA), and N-omega-nitro-L-arginine-methyl ester (L-NAME) groups. Mean arterial pressure was significantly higher in four hypertensive groups compared with control and sham groups, but there were no significant differences either among hypertensive groups or between sham and control groups. At the end of the experimental period, flash visual evoked potentials were recorded. The mean latencies of P1, N1, P2, N2, and P3 components were significantly prolonged in all hypertensive groups compared with the control and sham groups. The mean latencies of all VEPs components in the L-NAME group were longer than in the other hypertensive groups. Thiobarbituric acid-reactive substances (TBARS) were determined as an indicator of lipid peroxidation. Our data showed that hypertension caused a significant increase of lipid peroxidation in brain and retinal tissues. Additionally, plasma renin activity (PRA) was highest in the 2K-1C group and lowest in the DOCA group.

Animals↗