Neuroscience Research Communications最新文献

{"title":"Possible involvement of nitric oxide in the modulation of photolytic flash-induced intercellular calcium waves in cultured astrocytes","authors":"K. Kawahara, S. Iwabuchi","doi":"10.1002/NRC.10073","DOIUrl":"https://doi.org/10.1002/NRC.10073","url":null,"abstract":"Waves of elevated intracellular free calcium that propagate between neighboring astrocytes are important for the intercellular communication between astrocytes as well as between neurons and astrocytes. In this study, intercellular calcium waves were evoked by focal photolysis of a caged calcium inophore in cultured astrocytes. The focal photolysis of the caged compound resulted in an increase of intracellular calcium in the flashed cells, and this increase then propagated to neighboring astrocytes. The evoked calcium increase was inhibited by incubating cells with an inhibitor of nitric oxide synthase as well as with a scavenger of nitric oxide (NO). In addition, treatment of cultures with an NO donor resulted in the marked enhancement of the photolytic flash-induced calcium rise in astrocytes. This enhancement was reversed by treatment with inhibitors of soluble guanylyl cyclase as well as of protein kinase G.","PeriodicalId":19198,"journal":{"name":"Neuroscience Research Communications","volume":"16 1","pages":"189-196"},"PeriodicalIF":0.0,"publicationDate":"2003-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85499297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"L‐arginine potentiates monosynaptic and polysnaptic spinal reflexes","authors":"N. Tasci, S. Ankaralı, Ş. Demir, S. Canan, C. Marangoz","doi":"10.1002/NRC.10071","DOIUrl":"https://doi.org/10.1002/NRC.10071","url":null,"abstract":"Nitric oxide (NO) is long been known to play a major role in a wide range of physiological functions as a neural messenger and a neurotransmitter. \u0000 \u0000 \u0000 \u0000The aim of this study was to investigate the effects of NO precursor L-arginine on monosynaptic and polysnaptic spinal reflexes in anaesthetized and spinalized cats. A polyethylene cannula was placed into the right carotid artery in order to monitor blood pressure and a blood-pressure-clamp was applied between 90–110 mmHg. After a dorsal laminectomy between L5 and S1, monosynaptic and polysnaptic spinal reflexes were evoked by electrical stimulation of gastrocnemius nerves. Following control recordings, administration of NO precursor, L-arginine in 500 μM, 1, 2, 5 mM (local) and 50, 100, 200, 500 mg/kg (i.v.) does significantly increased the monosynaptic and polysnaptic reflex amplitude in a dose dependent manner. L-arginine appears to be more effective on polysnaptic reflexes than on monosynaptic reflexes. D-arginine, an ineffective enantiomer of L-ariginine was also tested as a control substance against L-arginine and it has no effects on the monosynaptic and polysnaptic reflexes. \u0000 \u0000 \u0000 \u0000These results suggest that L-arginine may play an excitatory role in modulation of spinal reflexes and this role may be mediated by NO in the cat spinal cord.","PeriodicalId":19198,"journal":{"name":"Neuroscience Research Communications","volume":"48 1","pages":"161-173"},"PeriodicalIF":0.0,"publicationDate":"2003-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80705526","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Calcium influx by hypertonicity through the voltage-dependent calcium channels","authors":"Hattori Toshimi","doi":"10.1002/NRC.10063","DOIUrl":"https://doi.org/10.1002/NRC.10063","url":null,"abstract":"We found out before the facts that propylene glycol (PG) raises the intracellular calcium concentration ([Ca2+]i) and that hypertonicity induced by PG is involved in the [Ca2+]i rise. The present study was conducted for the purpose of determining whether the Ca2+ influx through the Ca2+ channels is related to the rise in [Ca2+]i incuded by hypertonicity. A Ca2+-free saline and all of the Ca2+ channel blockers CdCl2 (0.1 mM), o-conotoxin GVIA (1 µM), verapamil (10 µM), and nicardipine (10 µM) significantly decreased the [Ca2+]i raised by hypertonicity. Bay K 8644 (4 µM), a Ca2+ channel activator, potentially increased the [Ca2+]i raised by hypertonic salines. The results described above lead me to the conclusion that the Ca2+ influx through the voltage-dependent Ca2+ channels is involved in the hypertonicity-induced [Ca2+]i rise.","PeriodicalId":19198,"journal":{"name":"Neuroscience Research Communications","volume":"67 1","pages":"89-94"},"PeriodicalIF":0.0,"publicationDate":"2003-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84080084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of prednisolone on β-secretase enzyme activity in vitro","authors":"Ko Ishikawa, Y. Imai, T. Tokuda, S. Ikeda","doi":"10.1002/NRC.10062","DOIUrl":"https://doi.org/10.1002/NRC.10062","url":null,"abstract":"Epidemiological studies have shown that anti-inflammatory medications decrease the incidence of Alzheimer's disease (AD). Our previous studies showed that a regimen of prednisolone decreased the amyloid β-protein (Aβ) concentration in the cerebrospinal fluid of AD patients. However, the detailed mechanism by which prednisolone decreased the Aβ concentration is unknown. In the present study we tested whether prednisolone has a direct inhibitory activity against β-secretase by using an in vitro enzyme assay system. β-Secretase, a fluorogenic substrate of β-secretase, and either prednisolone or β-secretase inhibitor were coincubated, and then the increase in fluorescence intensity was monitored. Prednisolone (1×10−3M–1×10−9) had no effect on the β-secretase activity, whereas β-secretase inhibitor inhibited it. This result shows it to be unlikely that prednisolone has an effect on the intracerebral Aβ metabolism via the modulation of β-secretase activity.","PeriodicalId":19198,"journal":{"name":"Neuroscience Research Communications","volume":"33 1","pages":"83-87"},"PeriodicalIF":0.0,"publicationDate":"2003-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82173045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Early contrast sensitivity loss and oxidative damage in healthy heavy smokers","authors":"I. Hepşen, E. Uz, S. Sogut, Sadik Büyükba, O. Akyol","doi":"10.1002/NRC.10067","DOIUrl":"https://doi.org/10.1002/NRC.10067","url":null,"abstract":"Objective: The purpose of this study was 1) to evaluate visual functions and the activities of antioxidant enzymes in plasma and erythrocytes in smokers in comparison with non-smokers, 2) to evaluate the correlations between visual functions and the oxidant/antioxidant system. We hypothesized that the changes in antioxidant system and consequently lipid peroxidation depend on smoking may affect sophisticated visual tests including contrast sensitivity (CS) and pattern visual evoked potentials (PVEP) \u0000 \u0000 \u0000 \u0000Subjects: This non-randomised control study included 24 chronic, heavy smokers who were smoking more than 20 cigarettes per day at least for last 10 years. Sixteen age and sex-matched, healthy, non-smokers were taken as controls. All volunteer subjects were accumulated from the outpatient clinic. To rule out the effect of alcoholism and malnutrition, we chose young, healthy heavy smokers who maintained adequate diet and who had no alcohol consumption history. \u0000 \u0000 \u0000 \u0000Following visual acuity and color vision tests, all subjects were applied to CS and PVEP tests. Values of CS, N75-P100 amplitude and P100 wave latency were compared between the study and control subjects. Superoxide dismutase (SOD) and catalase (CAT) activities in plasma and erythrocytes were determined by spectrophotometer. Plasma malondialdehyde (MDA) level, as an end product of lipid peroxidation, was assessed by spectrofluorometric method. \u0000 \u0000 \u0000 \u0000Results: CS was determined to be significantly reduced in smokers compared to non-smokers, although central vision and PVEP responses were not affected. Erythrocyte SOD activity and plasma MDA levels were significantly increased in smokers compared to controls. There were positive correlations between plasma SOD and erythrocyte SOD; CS and erythrocyte SOD; and CS and plasma SOD. \u0000 \u0000 \u0000 \u0000Conclusions: The results suggest the possible association between early CS loss and increase in antioxidant enzyme activities thus reflecting an increased oxidative damage due to cumulative effect of chronic smoking. Elevated concentrations of lipid peroxidation products in the plasma of smokers may directly show the increased oxidative damage in these subjects.","PeriodicalId":19198,"journal":{"name":"Neuroscience Research Communications","volume":"162 1","pages":"123-133"},"PeriodicalIF":0.0,"publicationDate":"2003-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76133005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interferon-beta treatment in multiple sclerosis patients decreases the number of monocytes in peripheral blood","authors":"Ö. Anlar, T. Tombul, H. Özbek, I. Dilek","doi":"10.1002/NRC.10061","DOIUrl":"https://doi.org/10.1002/NRC.10061","url":null,"abstract":"Multiple sclerosis (MS) is a demyelinating disease of the central nervous system, characterized by the presence of sclerotic lesions throughout the brain. During clinical activity, monocytes activation markers such as Interleukin 1 and tumor necrosis factor-alpha (TNF-α) increase. The effect of interferon beta (IFN-β) in reducing exacerbation rate and in slowing sustained worsening of disability has been shown in MS. The aim of this study was to determine levels of monocytes percentage in peripheral blood of MS patients receiving IFN-β. \u0000 \u0000 \u0000 \u0000We carried out this study in two groups of MS patients and a group of healthy subjects. First (study) group consisted of 13 patients treated by INF-β. The control groups consisted of a) 14 MS patients group with no treatment by INF-β and b) 20 healthy subjects. We counted the percentage of monocytes in the study group before and after one year of treatment by IFN-β and in the control groups patients in the same period. At the end of one year, there was a significant reduction in the percentage of monocytes in peripheral blood of MS patients treated by interferon.","PeriodicalId":19198,"journal":{"name":"Neuroscience Research Communications","volume":"52 1","pages":"77-81"},"PeriodicalIF":0.0,"publicationDate":"2003-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90836563","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effect of long‐term therapy with sodium valproate on oxidant/antioxidant status in epileptic children","authors":"E. Ozerol, M. Aslan, E. A. Çakmak, M. Gulec, C. Yakinci, O. Akyol","doi":"10.1002/NRC.10066","DOIUrl":"https://doi.org/10.1002/NRC.10066","url":null,"abstract":"Antiepileptic drugs may cause the changes in the oxidant/antioxidant status of the body. Reactive oxygen species have been suggested to be an important factor in the pathogenesis of various diseaases as well as drug interactions and/or adverse effects. The aim of this study, therefore, is to investigate the status of major antioxidant enzyme activities as well as the end products of lipid peroxidation in erythrocyte and plasma from epileptic children after therapy with sodium valproate (VPA). Superoxide dismutase (SOD), catalase (CAT) activities and malondialdehyde (MDA) levels in erythrocyte and plasma were analyzed in 41 epileptic patients under long-term antiepileptic therapy with VPA and 32 healthy controls. Erythrocyte SOD activity was found to be increased (p=0.024) whereas erythrocyte CAT activity decreased (p=0.016) in patients with epilepsy under VPA treatment compared to the controls. MDA levels in erythrocyte were found to be markedly decreased in epileptic children compared to controls (p<0.001). In conclusion, decreased CAT activity seems to be compensated with increased SOD activity in erythrocytes protecting erythrocyte membranes from lipid peroxidation in patients with epilepsy under VPA treatment.","PeriodicalId":19198,"journal":{"name":"Neuroscience Research Communications","volume":"27 1","pages":"115-122"},"PeriodicalIF":0.0,"publicationDate":"2003-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83846718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterisation of catalytic nucleic acids targeting the survival of motor neuron messenger RNA","authors":"B. Trülzsch, K. Davies, M. Wood","doi":"10.1002/NRC.10064","DOIUrl":"https://doi.org/10.1002/NRC.10064","url":null,"abstract":"Catalytic nucleic acids have been used in a reverse genetics approach to study gene function. We are interested in applying this technology to study the autosomal recessive disease Spinal Muscular Atrophy (SMA) which is caused by loss of survival motor neuron gene (SMN) product leading to progressive motor neuron loss and muscular atrophy. Although the SMN gene is ubiquitously expressed, the cause for selective motor neuron loss is unknown. Embryonal lethality in mice has made it extremely difficult to generate animal models of SMA. We describe a procedure for selecting effective DNAzymes (DZ) and ribozymes (RZ) based on their ability to cleave the full length Smn mRNA at low magnesium concentrations, after a short time period, and at a low catalytic nucleic acid to target ratio. Using these criteria three effective RZ and DZ were generated. These results indicate that catalytic nucleic acids can effectively cleave Smn target RNA in an environment closely resembling that present in the cell and thus have potential for interference with Smn gene expression in cells and in vivo.","PeriodicalId":19198,"journal":{"name":"Neuroscience Research Communications","volume":"51 1","pages":"95-106"},"PeriodicalIF":0.0,"publicationDate":"2003-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85577705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hair lead and cadmium concentrations in patients with epilepsy and migraine","authors":"S. Şaşmaz, E. Uz, T. Pınar, H. Vural, Mcahit Eiri, Atilla Ilihan, M. Akyol","doi":"10.1002/NRC.10065","DOIUrl":"https://doi.org/10.1002/NRC.10065","url":null,"abstract":"Epilepsy and migraine are neurological manifestations of neurocutaneous diseases. The studies that investigate the etiology of these manifestations may illuminate the physiopathological bases of neurocutaneous disorders. The hypothesis that the elevation of toxic trace element concentration in the brain is an important triggering factor for seizures and subsequent neuronal damage in epilepsy and migraine was investigated in this clinical prospective study. \u0000 \u0000 \u0000 \u0000The levels of two heavy metals (lead [Pb] and cadmium [Cd]) in scalp hair were measured in patients with epilepsy (n=33) and migraine (n=40) as well as healthy control subjects (n=26). The hair concentration of these two toxic trace elements was determined by atomic absorption spectrophotometry. There was a significant increase in Pb concentration in epilepsy group when compared to both control (p<0.006) and migraine group (p<0.02). There was no difference in mean Cd concentration of hair from epilepsy, migraine patients and control groups. Therefore, no conclusive findings were obtained for CD. Elevated Pb content in epileptic patients was accepted as being of particular importance. Our findings support the hypothesis that the elevation in Pb concentration in the scalp hair amongst patients with epilepsy may show the elevation in the brain and constitute an important triggering factor for seizures.","PeriodicalId":19198,"journal":{"name":"Neuroscience Research Communications","volume":"26 1","pages":"107-114"},"PeriodicalIF":0.0,"publicationDate":"2003-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78834615","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"INVOLVEMENT OF NITRIC OXIDE IN PARKINSON'S DISEASE: EMPHASIS ON SEX DIFFERENCE IN PREVALENCE","authors":"D. Taşkıran, B. Nazlıel, C. Irkec, F. Kutay, S. Pogun","doi":"10.1002/NRC.10068","DOIUrl":"https://doi.org/10.1002/NRC.10068","url":null,"abstract":"SUMMARY Parkinson’s disease (PD) is characterized by severe movement disorders. Excessive production of reactive oxygen species has been implicated as a possible mediator of neurodegenerative changes in nigrostriatal neurons in PD. Nitric oxide (NO) has received substantial attention among pathophysiological factors underlying glutamate neurotoxicity in neurodgenerative disorders including PD. PD is more prevalent in men than in women by an approximate 3:2 ratio; the nitrergic systems are also more active in males than females. In this study, NOZ- +NOJ- (stable metabolites of NO) levels were determined in sera of PD patients (n=20) and control subjects (n=I6). NOz-+NOjLevels were higher in PD patients compared to controls, and in males compared to females. Furthermore, there was a correlation between age and NO metabolites in females but not in males. These data support a role for NO in PD and provide further evidence for sex differences in NO activity that may underlie neurodegenerative disorders.","PeriodicalId":19198,"journal":{"name":"Neuroscience Research Communications","volume":"35 11","pages":"135-142"},"PeriodicalIF":0.0,"publicationDate":"2003-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72620980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}