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Ulusoy HB, Sonmez MF, Kilic E, Caliskan K, Karaca B, Kara M, Ercal O, Gunduz Y, Karabulut D, Bitiktas S, Tan B, Kavraal S, İnal A, Suer C. Intraperitoneal Administration of Low Dose Aluminium in The Rat: How Good is It to Produce a Model for Alzheimer Disease. Arch Ital Biol 2016; 153:266-78. [PMID: 27168412 DOI: 10.12871/00039829201543] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Since neurotoxicity of aluminium (Al) resembles the progressive neurodegeneration observed in Alzheimer Disease (AD), Al administration in several ways has been used to produce AD model. Intraperitoneal (ip) low dose (4.2 mg/ kg) Al injection in rats for long periods is the preferred method by some researchers. In this paper, the efficiency of this method for producing an AD model was evaluated. In this study, we looked at the neuropathology of Al and the characteristic lesions of AD by histological and immunohistochemical techniques and determined oxidative stress markers in the brains of Al-treated and control rats. We also made electrophysiological recordings at the hippocampus and evaluated possible behavioural changes by Morris water maze test. However, no pathologic changes occurred in the animals except for an impairment in long-term potentiation (LTP) in the hippocampus (e.g. the LTPs of population spike (PS) amplitude at 15 min post-tetanus were measured as 217±27% in Al-treated rats and as 240±42% in sham-treated rats, of baseline PS amplitude). According to the findings of the present study, low dose of ip Al in rats is not sufficient to produce a good AD model. Higher doses (≥10 mg/kg) should be used.
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Elmarzouki H, Aboussaleh Y, Bitiktas S, Suer C, Artis AS, Dolu N, Ahami A. Effects of cold exposure on behavioral and electrophysiological parameters related with hippocampal function in rats. Front Cell Neurosci 2014; 8:253. [PMID: 25225472 PMCID: PMC4150461 DOI: 10.3389/fncel.2014.00253] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Accepted: 08/10/2014] [Indexed: 11/13/2022] Open
Abstract
Aim: Behavioral and mental changes may occur in people exposed to cold stress by decreasing their work efficiency and their mental capacity while increasing the number of accidents on the job site. The goal of this study was to explore the effect of cold stress in spatial learning performance excitability and LTP. Materials and Methods: Three to four month old rats were randomly divided into four groups to form a control group and a cold stress group for each sex. The groups of cold stressed animals were placed in a cold room ambient temperature of 4°C for 2 h day. Adrenal glands and body weight (g) were recorded in control and stressed rats during the cold exposure. Spatial learning (acquisition phase) and memory (probe trial) were tested in the Morris water maze (MWM) immediately after daily exposure. Latency to locate the hidden platform, distance moved (DM), mean distance to platform, swim speed (SS) and time spent in the platform quadrant were compared between genders and treatments. Field potential recordings were made, under urethane anesthesia, from the dentate gyrus (DG) granule-cell layer, with stimulation of the medial perforant pathway 2 h after the probe trial. This study examined spatial memory as measured by MWM performance and hippocampal long-term potentiation (LTP) in the DG after exposure to cold in a repeated stress condition for 2 h/day for 5 days. Results: The cold-exposed female rats needed less time to find the hidden platform on day 1 (43.0 ± 13.9 s vs. 63.2 ± 13.2 s), day 2 (18.2 ± 8.4 s vs. 40.9 ± 12.2 s) and on day 4 (8.0 ± 2.1 s vs. 17.2 ± 7.0 s) while cold-exposed male rats showed a decreased escape latency (EL) on day 1 only (37.3 ± 12.5 s vs. 75.4 ± 13.1 s). Cold-exposed male rats spent less time in the target quadrant (30.08 ± 6.11%) than the control male rats (37.33 ± 8.89%). Two hour cold exposure decreased population spike (PS) potentiation during both induction (218.3 ± 21.6 vs. 304.5 ± 18.8%) and maintenance intervals (193.9 ± 24.5 vs. 276.6 ± 25.4%) in male rats. Meanwhile cold exposure did not affect the body weight (C: 221 ± 2.5 vs. S: 222 ± 1.7) but it impacts the adrenal gland relative weight (S: 27.1 ± 1.8 mg vs. C: 26.2 ± 1.4 mg). Conclusion: Overall, the results show that repeated cold exposure can selectively improve spatial learning in adult female rats, but impaired retention memory for platform location in male rats. It is possible that impaired LTP underlies some of the impaired retention memory caused by cold exposure in the male rats.
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Affiliation(s)
- Hajar Elmarzouki
- Laboratory of Nutrition and Health, Department of Biology, Faculty of Science, Ibn Tofail University Kenitra, Morocco
| | - Youssef Aboussaleh
- Laboratory of Nutrition and Health, Department of Biology, Faculty of Science, Ibn Tofail University Kenitra, Morocco
| | - Soner Bitiktas
- Department of Physiology, Erciyes University School of Medicine Kayseri, Turkey
| | - Cem Suer
- Department of Physiology, Erciyes University School of Medicine Kayseri, Turkey
| | - A Seda Artis
- Department of Physiology, Medeniyet University School of Medicine İstanbul, Turkey
| | - Nazan Dolu
- Department of Physiology, Erciyes University School of Medicine Kayseri, Turkey
| | - Ahmed Ahami
- Laboratory of Nutrition and Health, Department of Biology, Faculty of Science, Ibn Tofail University Kenitra, Morocco
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Tanriverdi F, Suer C, Yapislar H, Kocyigit I, Selcuklu A, Unluhizarci K, Casanueva FF, Kelestimur F. Growth hormone deficiency due to sports-related head trauma is associated with impaired cognitive performance in amateur boxers and kickboxers as revealed by P300 auditory event-related potentials. Clin Endocrinol (Oxf) 2013; 78:730-7. [PMID: 22994791 DOI: 10.1111/cen.12037] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Revised: 08/18/2012] [Accepted: 08/31/2012] [Indexed: 11/29/2022]
Abstract
OBJECTIVES It has been recently reported that boxing and kickboxing may cause pituitary dysfunction, GH deficiency in particular. The strong link between poor cognitive performance and GH deficiency due to causes other than head trauma and the improvement of cognitive function after GH replacement therapy have been previously shown. P300 auditory event-related potential (ERP) measure is widely used to evaluate cognitive performance. In this study, we investigated the relation between the GH-IGF-I axis and cognitive performance in boxers and kickboxers. DESIGN AND PATIENTS Forty-one actively competing or retired male boxers (n: 27) and kickboxers (n: 14) with a mean age of 29·04 ± 9·30 year and 14 age- and education-matched healthy male controls were included in the study. For neuropsychological tests, the mini-mental state examination (MMSE) and Quality of Life Assessment of GH Deficiency in Adults (QoL-AGHDA) questionnaires were administered. Moreover, cognitive performance was evaluated according to P300 ERPs. RESULTS Nine of 41 (21·9%) athletes had GH deficiency. P300 amplitudes were lower at all electrode sites in the GH-deficient group than in controls, and the differences were statistically significant at Fz and Oz electrode sites (P < 0·05). When GH-deficient athletes were compared with GH-sufficient athletes, the P300 amplitudes were lower at all electrode sites in the GH-deficient group; these differences were statistically significant at Fz, Pz and Cz electrode sites (P < 0·05). In all athletes, there were significant negative correlations between IGF-I levels vs P300 latencies, and there were significant positive correlations between IGF-I levels vs P300 amplitudes (P < 0·05). CONCLUSION This study provides the first electrophysiological evidence for the close relation between the P300 ERPs and the GH-IGF-I axis in boxers and kickboxers.
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Affiliation(s)
- Fatih Tanriverdi
- Department of Endocrinology, Erciyes University Medical School, Kayseri, Turkey.
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Kavraal S, Oncu SK, Bitiktas S, Artis AS, Dolu N, Gunes T, Suer C. Maternal intake of Omega-3 essential fatty acids improves long term potentiation in the dentate gyrus and Morris water maze performance in rats. Brain Res 2012; 1482:32-9. [DOI: 10.1016/j.brainres.2012.09.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 08/03/2012] [Accepted: 09/01/2012] [Indexed: 10/27/2022]
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Artis AS, Bitiktas S, Taşkın E, Dolu N, Liman N, Suer C. Experimental hypothyroidism delays field excitatory post-synaptic potentials and disrupts hippocampal long-term potentiation in the dentate gyrus of hippocampal formation and Y-maze performance in adult rats. J Neuroendocrinol 2012; 24:422-33. [PMID: 22070634 DOI: 10.1111/j.1365-2826.2011.02253.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Manipulations of thyroid hormones have been shown to influence learning and memory. Although a large body of literature is available on the effect of thyroid hormone deficiency on learning and memory functions during the developmental stage, electrophysiological and behavioural findings, particularly on propylthiouracil administration to adult normothyroid animals, are not satisfactory. The experiments in the present study were carried out on 12 adult male Wistar rats aged 6-7 months. Hypothyroidism was induced by administering 6-n-propyl-2-thiouracil in their drinking water for 21 days at a concentration of 0.05%. The spatial learning performance of hypothyroid and control rats was studied on a Y-maze. The rats were then placed in a stereotaxic frame under urethane anaesthesia. A bipolar tungsten electrode was used to stimulate the medial perforant path. A glass micropipette was inserted into the granule cell layer of the ipsilateral dentate gyrus to record field excitatory post-synaptic potentials. After a 15-min baseline recording of field potentials, long-term potentiation was induced by four sets of tetanic trains. The propylthiouracil-treated rats showed a significantly attenuated input-output (I/O) relationship when population spike (PS) amplitudes and field excitatory post-synaptic potentials (fEPSP) were compared. fEPSP and PS latencies were found to be longer in the hypothyroid group than in the control group. The PS amplitude and fEPSP slope potentiations in the hypothyroid rats were not statistically different from those in the control rats, except for the field EPSP slope measured in the post-tetanic and maintenance phases. The hypothyroid rats also showed lower thyroxine levels and poor performance in the spatial memory task. The present study provides in vivo evidence for the action of propylthiouracil leading to impaired synaptic plasticity, which might explain deficit in spatial memory tasks in adult hypothyroid rats.
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Affiliation(s)
- A S Artis
- Department of Physiology, Faculty of Medicine, Erciyes University, Kayseri, Turkey
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Suer C, Dolu N, Artis AS, Sahin L, Aydogan S. Electrophysiological evidence of biphasic action of carnosine on long-term potentiation in urethane-anesthetized rats. Neuropeptides 2011; 45:77-81. [PMID: 21163526 DOI: 10.1016/j.npep.2010.11.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2010] [Revised: 11/24/2010] [Accepted: 11/24/2010] [Indexed: 10/18/2022]
Abstract
Carnosine is a dipeptide synthesized by the carnosine synthetase from β-alanine and l-histidine. The well-known effects of carnosine may be related with mechanisms producing long-term potentiation which is one of the electrophysiological signs of memory. In the present study we aimed to investigate the effect of four different doses of carnosine on long-term potentiation in urethane-anesthetized rat. A bipolar stimulating electrode was placed in the medial perforant path and a double-barrel glass micropipette was placed in the dentate gyrus as the recording electrode. Artificial cerebrospinal fluid (in the control group) or carnosine (0.1, 1, 10, and 100μg/μL) was infused into the dentate gyrus. Our results showed that the I/O curve of the excitatory postsynaptic potential slope or population spike amplitude was not significantly shifted by carnosine. We found that population spike amplitude increased to 244% and 287% at the dose of 100μg/μL in the post-tetanic and induction phases, respectively, but decreased to 163% and 186% at the dose of 0.1μg/μL and to 145% and 162% at the dose of 1μg/μL when compared with 203% and 232% of the control values. However, there were no significant differences for the slope of excitatory postsynaptic potential. Carnosine had no effect on the EPSP slope or PS amplitude recorded from the dentate gyrus in response to test stimuli when high-frequency stimulation was not delivered. In the present study, we speculated that the effects of carnosine in lower or higher doses could be explained by its effect on different processes, such as soluble guanylyl cyclase inhibition or the conversion of carnosine into histamine.
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Affiliation(s)
- Cem Suer
- Department of Physiology, Faculty of Medicine, Erciyes University, 38039 Kayseri, Turkey.
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Abstract
In this study, using auditory sequences, the authors designed an examination with three phases of stimulus-driven attention that is based on the possibility that involuntarily time shifts of attention are caused by nonunique stimulus properties. The purpose was to investigate whether attending and temporal expectancies are influenced by stimulus's properties and by sex. In each phase, an auditory stimulus train was presented, and the participant was asked to tap rhythmically in order to anticipate every fifth stimulus (or, in the third phase, the lack of it). The time between button pressing and stimulus onset was measured using a computer. Time estimation was accepted as a false response if the subject responded before 150 ms or 150 ms later from onset stimulus time. Error numbers were greater in Phase 3 and there was no significant difference between the male and female subjects for any of the phases when error numbers were compared. On the other hand, males pressed the button more accurately than females. Time estimation performance was affected by sex and expectancy-related motor responses are very important for time estimation.
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Affiliation(s)
- Nazan Dolu
- University of Erciyes, Faculty of Medicine, Department of Physiology,Kayseri, Turkey.
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Tanriverdi F, Yapislar H, Karaca Z, Unluhizarci K, Suer C, Kelestimur F. Evaluation of cognitive performance by using P300 auditory event related potentials (ERPs) in patients with growth hormone (GH) deficiency and acromegaly. Growth Horm IGF Res 2009; 19:24-30. [PMID: 18567522 DOI: 10.1016/j.ghir.2008.05.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2008] [Revised: 04/08/2008] [Accepted: 05/09/2008] [Indexed: 11/21/2022]
Abstract
CONTEXT Impaired cognitive performance has been demonstrated in adults with GH deficiency and acromegaly by using different neuropsychological tests. P300 event related potential (ERP) application is a well established neurophysiological approach in the assessment of cognitive performance. OBJECTIVES Evaluation of cognitive performance by using P300 ERPs has not been reported in acromegaly, and the comparisons of the P300 ERPs between the patients with GH deficiency and GH excess have not been done yet. Therefore present study was designed to investigate the effects of GH deficiency and GH excess on cognitive performance by using P300 ERPs. DESIGN AND METHODS The study comprised 19 patients with severe GH deficiency, 18 acromegalic patients and 16 age, education and sex matched healthy controls. Baseline auditory ERPs were obtained at Fz (frontal), Cz (central), Pz (parietal) and Oz (occipital) electrode sites in GH deficient group, GH excess group and control group. RESULTS There was a significant difference between mean serum IGF-I levels in the GH deficient and acromegalic patients (48+/-38 ng/ml and 742+/-272 ng/ml, respectively) (P=0.01). The mean P300 latency of the patients with GH deficiency was significantly (P=0.0001) prolonged when compared with that of normal controls and acromegalic patients at all electrode sites. The mean P300 amplitude of the patients with acromegaly was significantly (P=0.005) lower when compared with that of normal controls and GH deficient patients at all electrode sites. CONCLUSIONS Using ERPs recordings, the present study indicates the prolongation of P300 latencies in patients with severe GH deficiency and reduction of P300 amplitudes in patients with acromegaly. This study provides the electrophysiological evidence for the presence of cognitive dysfunction in both GH deficiency and GH excess, and different components of the cognitive performance are impaired in these conditions.
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Affiliation(s)
- F Tanriverdi
- Department of Endocrinology, Erciyes University Medical School, 38039 Kayseri, Turkey
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Ascioglu M, Arslan M, Suer C, Ascioglu O, Ozesmi C, Borlu M, Coskun A, Gonul AS, Koseoglu E. P50 variations in Behcet`s patients without neurologic findings. Neurosciences (Riyadh) 2007; 12:50-52. [PMID: 21857619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
OBJECTIVE In the present study, subclinical lesion involvement was investigated using the P50 component in Behcet`s patients without neurological manifestation. METHODS We performed this clinical research in Erciyes University, Faculty of Medicine between December 2000 and November 2001. The studies were carried out on 18 Behcet`s patients without neurologic findings and 18 volunteers for control. Standard Ag/AgCl electrodes in plastic cups were used for monopolar EEG derivations. They were attached with electrode paste and tape at the Cz (vertex) according to the 10-20 system. The auditory stimuli were delivered in pairs. The P50 waves, which may be taken from approximately 50 msec from the stimuli, were collected by computer system. Amplitudes and latencies of the P50 components were measured in the same system. RESULTS This study showed that the suppression of P50 responses performed by the test stimuli, was significantly more decreased in Behcet`s patients than the control subjects. CONCLUSION The decrease of the suppression of the auditory P50 response to repeated stimuli reflects a deficit in the central nervous system`s ability, such as attention, cognition, and sensory input in Behcet`s patients and can be used as a neurophysiological marker in subclinical lesions in these patients.
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Affiliation(s)
- Meral Ascioglu
- Department of Physiology, Faculty of Medicine, University of Erciyes, Kayseri, Turkey
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Golgeli A, Tanriverdi F, Suer C, Gokce C, Ozesmi C, Bayram F, Kelestimur F. Utility of P300 auditory event related potential latency in detecting cognitive dysfunction in growth hormone (GH) deficient patients with Sheehan's syndrome and effects of GH replacement therapy. Eur J Endocrinol 2004; 150:153-9. [PMID: 14763913 DOI: 10.1530/eje.0.1500153] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Impaired cognitive function has been demonstrated in adults with growth hormone (GH) deficiency (GHD) by using different neuropsychological tests. Despite several studies, present knowledge about the impact of GHD and GH replacement therapy (GHRT) on cognitive function is limited. P300 event-related potential (ERP) application is a well-established neurophysiological approach in the assessment of cognitive functions including the updating of working memory content and the speed of stimulus evaluation. GHD is a well-known feature of Sheehan's syndrome and cognitive changes due to GHD and the effects of GHRT remain to be clarified. The present study was designed to investigate the effects of GHD and 6 months of GHRT on cognitive function in patients with Sheehan's syndrome by using P300 latency. DESIGN AND METHODS The study comprised 14 patients with Sheehan's syndrome (mean age, 49.5+/-7.8 years) and 10 age-, education- and sex-matched healthy controls. With hormone replacement therapy, basal hormone levels other than GH were stable before enrollment and throughout the GHRT. The diagnosis of GH deficiency was established by insulin-tolerance test (ITT), and mean peak level of GH in response to insulin hypoglycemia was 0.77+/-0.35 mIU/l. Treatment with GH was started at a dose of 0.45 IU (0.15 mg)/day in month 1, was increased to 0.9 IU (0.30 mg)/day in month 2 and was maintained at 2 IU (0.66 mg)/day. Initially baseline auditory ERPs in patients and controls were recorded at frontal (Fz), central (Cz), and parietal (P3 and P4) electrode sites. In the patient group, ERPs were re-evaluated after 6 months of GH replacement therapy. During each session P300 amplitude and latency were measured. RESULTS Mean serum insulin-like growth factor-I (IGF-I) concentration in the patient group before GHRT was 23+/-13 ng/ml. After 6 months of GH therapy mean IGF-I significantly increased to an acceptable level, 234+/-71 ng/ml (P<0.05). The mean latencies (at all electrode sites) of the patients before GHRT were found to be significantly prolonged when compared with those of normal controls (P<0.05). After 6 months of GHRT mean P300 latencies (at all electrode sites) were decreased significantly when compared with latencies before treatment (P<0.05). CONCLUSIONS The present study, using P300 ERP latencies, therefore suggests an impairment of cognitive abilities due to severe GHD in patients with Sheehan's syndrome and an improvement of cognitive function after 6 months of physiological GHRT. Moreover, this was a novel application of P300 ERP latencies in cognitive function detection in patients with GHD. Further studies with different patient groups need to be done to assess the clinical use of this electrophysiological method in the diagnosis of cognitive dysfunction due to GHD.
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Affiliation(s)
- A Golgeli
- Department of Physiology, Erciyes University Medical School, 38039 Kayseri, Turkey
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Abstract
Reduced auditory P300 amplitude generally has been considered to be a trait marker of schizophrenia, independent of antipsychotic treatment and clinical symptoms. However, several seemingly well-conducted studies have found P300 amplitude to be a state marker correlated with clinical symptoms. Recent research on atypical antipsychotics indicate that these medications may alter P300 amplitude as well as having beneficial clinical effects. The objective of the present study was to further elucidate the effects of schizophrenia, symptom severity, and medication status on the P300. The baseline auditory P300 was assessed in unmedicated schizophrenic patients who then were treated with olanzapine for 6 weeks and reassessed. Healthy control subjects were assessed at baseline and again at 6 weeks. Compared to healthy controls, the unmedicated patients' P300s were attenuated and delayed prior to treatment. Subsequent antipsychotic treatment increased the patients' P300 amplitudes without affecting latency. Frontal P300 amplitude was normalized, but parietal P300 amplitude remained below that of healthy controls. Although olanzapine was effective in reducing the patients' symptoms, there were no correlations between symptoms and P300 amplitude or latency either before or after treatment. The results of the present study lend support to the view that P300 amplitude behaves as a trait marker. No evidence is found of a P300 clinical state marker.
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Affiliation(s)
- Ali Saffet Gonul
- Department of Psychiatry, Ege University, School of Medicine, 35100 Izmir, Turkey.
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Dolu N, Özesmi CD, Suer C, Keleştimur F. ELECTRODERMAL RESPONDING IN HYPERTHYROID PATIENTS. Indian J Physiol Pharmacol 1999; 43:79-83. [PMID: 27093741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The effects of hyperthyroidism on electrodermal habituation and responsiveness were examined in 43 hyperthyroid patients who were divided in two groups (medicated and unmedicated). In a comparison of 43 hyperthyroid and 43 normal controls; among patients with hyperthyroidism a great number of nonresponders were found. The distributions of SCR in habituation series in both group were almost the same but hyperthyroid patients were in slower habituation status than controls. These findings suggest that electrodermal nonresponsiveness or slow habituation in hyperthyroid patients might be considered as a function due to changes in the metabolism of biogenic mines in the central nervous system.
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Affiliation(s)
- N Dolu
- Department of Physiology, Faculty of Medicine, University of Erciyes, 38039 Kayseri, Turkey
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Abstract
In this study, we investigated whether nicotine may have a local anaesthetic action in mice, using the tail press and tail immersion tests. Nicotine increased the latent time of biting the clip in the tail press test (p < 0.001) and retarded tail withdrawal latency in the tail immersion test (p < 0.01), compared to controls. These results suggest that nicotine may possess a local anaesthetic action.
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Affiliation(s)
- A Erenmemisoglu
- Department of Pharmacology, Medical Faculty, Erciyes University, Kayseri, Turkey
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Abstract
In this study, endurance time in swimming exercise was evaluated in rats. Subcutaneous (S.C.) injection of nicotine decreased the endurance time in swimming exercise significantly, in a dose-dependent manner compared to the control group. At the dose of 0.125 mg/kg nicotine, the endurance time in swimming exercise remained unchanged, while at the doses of 0.25 and 0.375 mg/kg, it decreased significantly (p < 0.05 and p < 0.01, respectively). This effect of nicotine was antagonized by pretreatment with hexamethonium 5 mg/kg S.C. These results suggest that nicotine may limit the physical performance.
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Affiliation(s)
- S Temocin
- Department of Physiology, Faculty of Medicine, Erciyes University, Kayseri, Turkey
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