Neurobiology (Budapest, Hungary)最新文献

{"title":"A light and electron microscopic analysis of the convergent retinal and visual cortical projections to the nucleus of the optic tract (NOT) in the pigmented rat.","authors":"T Shintani,&nbsp;K Hoshino,&nbsp;R Meguro,&nbsp;T Kaiya,&nbsp;M Norita","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>It is generally known that the nucleus of the optic tract (NOT) subserves visuomotor relations between the retina and preoculomotor structures as the only subcortical pathway mediating optokinetic responses (OKR) in mammals. We have examined the projections from the retina and visual cortical areas (areas 17, 18a and 18b) to NOT using tracers (wheat germ agglutinin-conjugated horseradish peroxidase, WGA-HRP and cholera toxin B subunit, CTB) in order to clarify how these two different functional inputs to OKR are organized. CTB injection into the vitreous body resulted in anterograde label almost exclusively in the contralateral NOT. Ultrastructually, the size of the retinal axon terminals was small (up to 0.7 micron in diameter), contained round synaptic vesicles and pale mitochondria, and made asymmetrical synaptic contacts with both GABA-positive and GABA-negative NOT neurons. Visual cortical area 17 and the transitional area between area 17 and 18a, or between area 17 and 18b projected their axons to the ipsilateral NOT. Ultrastructually, the size of the cortical axon terminals was small (up to 0.5 micron in diameter), contained round synaptic vesicles, and made asymmetrical synaptic contacts only with GABAnegative NOT neurons. With light and electron microscopical observation, there was a considerable overlap in the cortico-NOT and retino-NOT projection pattern: GABA-negative (presumably NOT projection) neurons simultaneously receive input from both cortical and retinal terminals. From these results, it seems reasonable to postulate that inputs from visual cortical areas in the pigmented rat cooperate with those from the retina in controlling OKR.</p>","PeriodicalId":79356,"journal":{"name":"Neurobiology (Budapest, Hungary)","volume":"7 4","pages":"445-60"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21738817","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 effects of long-term heparin application on ACh-induced isolated ileum contractility and structure.","authors":"E. Koç, N. Zaloğlu, Y. Saran, B. Turan","doi":"10.1016/S0928-4680(98)81049-3","DOIUrl":"https://doi.org/10.1016/S0928-4680(98)81049-3","url":null,"abstract":"","PeriodicalId":79356,"journal":{"name":"Neurobiology (Budapest, Hungary)","volume":"151 1","pages":"33-43"},"PeriodicalIF":0.0,"publicationDate":"1998-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74536057","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":"Maitotoxin, a cationic channel activator.","authors":"L I Escobar,&nbsp;C Salvador,&nbsp;M Martínez,&nbsp;L Vaca","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Maitotoxin (MTX), a water soluble polyether obtained from the marine dinoflagellate Gambierdiscus toxicus is one of the entities responsible for Ciguatera, a form of seafood poisoning. This toxin is a potent activator of changes in the intracellular Ca2+ concentrations of cells from a wide variety of organisms. Evidence published in the last few years strongly suggests that this toxin has no ionophoretic activity. Molecular mechanics studies, shown for the first time in this review, models MTX as a molecular 'wire'. The present work compiles the few studies developed with electrophysiological techniques. All these reports indicate that MTX is activating a voltage independent, nonselective cationic channel, which in some preparations requires the presence of extracellular Ca2+ for channel activation. The conductance estimated from a variety of tissues is in the order of 12-40 pS. Thus far, no specific blocker has been identified for this channel. The nature of the MTX receptor remains a mistery.</p>","PeriodicalId":79356,"journal":{"name":"Neurobiology (Budapest, Hungary)","volume":"6 1","pages":"59-74"},"PeriodicalIF":0.0,"publicationDate":"1998-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20629877","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":"Biochemical effects induced by REM sleep deprivation in naive and in D-amphetamine treated rats.","authors":"A Lara-Lemus,&nbsp;R Drucker-Colín,&nbsp;J Méndez-Franco,&nbsp;M Palomero-Rivero,&nbsp;M Pérez de la Mora","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The neurochemical dysfunction present in patients showing self-mutilating behavior (SMB) is not well understood. In animal models, rapid eye movement (REM) sleep deprivation enhances the SMB induced by the chronic administration of d-amphetamine. To understand the mechanism underlying these effects the levels of dopamine (DA), noradrenaline (NA) and serotonin (5-HT) were measured in REM sleep deprived only, and in REM sleep deprived and d-amphetamine treated rats. DA levels were elevated (31%) after REM sleep deprivation (48 h) in the neostriatum and the cerebral cortex (33%), while the levels of NA and 5-HT remained constant. A 6-day treatment with d-amphetamine (7.5 mg/kg; i.p.) failed to affect, in REM sleep deprived rats, DA, NA and 5-HT levels. It was also found that REM sleep deprivation had no effects on the d-amphetamine induced [3H]DA release from slices of the same regions. Our results suggests that dopaminergic mechanisms are involved in the effects of REM sleep deprivation on SMB.</p>","PeriodicalId":79356,"journal":{"name":"Neurobiology (Budapest, Hungary)","volume":"6 1","pages":"13-22"},"PeriodicalIF":0.0,"publicationDate":"1998-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20629924","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":"Amyloid beta-peptide and its fragments induce acetylcholine release in in vitro basal forebrain tissue slices of rat brain, but do not affect the choline uptake.","authors":"M Forgon,&nbsp;Z Farkas,&nbsp;K Gulya,&nbsp;M Pakaski,&nbsp;B Penke,&nbsp;P Kasa","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":79356,"journal":{"name":"Neurobiology (Budapest, Hungary)","volume":"6 3","pages":"359-61"},"PeriodicalIF":0.0,"publicationDate":"1998-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20690670","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":"Neuron clusters of segmental nerves of a ventral nerve cord ganglion in Lumbricus terrestris.","authors":"A Zsombok,&nbsp;L Molnár","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":79356,"journal":{"name":"Neurobiology (Budapest, Hungary)","volume":"6 4","pages":"455-8"},"PeriodicalIF":0.0,"publicationDate":"1998-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21091467","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":"Evaluation of chronic intrathecal catheterization in rats.","authors":"I Dobos,&nbsp;G Horváth,&nbsp;M Szikszay,&nbsp;G Benedek","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":79356,"journal":{"name":"Neurobiology (Budapest, Hungary)","volume":"6 4","pages":"469-70"},"PeriodicalIF":0.0,"publicationDate":"1998-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21091472","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":"Nitric oxide synthase and the acetylcholine receptor in the prefrontal cortex: metasynaptic organization of the brain.","authors":"B Csillik,&nbsp;J Nemcsók,&nbsp;I Boncz,&nbsp;E Knyihár-Csillik","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Nitric oxide synthase (NOS) and the nicotinic acetylcholine receptor (nAChR) immunoreactivity of the cerebral cortex was studied in adult Macaca fascicularis monkeys at light- and electron microscopic levels. NOS was located by means of the polyclonal antibodies developed by Transduction Laboratories (Lexington, KY, USA), as primary serum, in a dilution of 1:1000, and nAChR was located by means of biotinylated alpha-bungarotoxin (BTX) obtained from Molecular probes (Eugene, Oregon, USA) in a dilution of 1:2000. While endothelial eNOS outlined blood vessels in the brain, brain-derived (neural) bNOS labelled three well-defined cell types in area 46 of the prefrontal cortex, viz. (a) bipolar cells, scattered through layers III to V, equipped with long dendrites which pass over the thickness of the cortex in a right angle to the pial surface, establishing dendritic bundles closely reminiscent of a columnar organization; (b) large multipolar cells, located mainly in layers V and VI, with axons which interconnect dendritic bundles of the bipolar cells and establish synapses with dendritic shafts and spines of the former; and (c) stellate cells, located in lamina II and III, which establish an axonal network in lamina zonalis (lamina I). This arrangement is most characteristic in area 46 of the prefrontal cortex; areas 10 and 12 display similar features. In contrast, the primary visual cortex (area 17), is lacking any sign of columnar organization. Localization of bNOS immunoreactivity is at marked variance to that of NADPH-diaphorase which labels large pyramidal cells in the primate cortex. Binding of alpha-bungarotoxin (BTX) which labels the alpha 7 subunit of nAChR is located in somata, dendrites and axons of interneurons scattered over the entire width of the prefrontal cortex; on the other hand, the monoclonal antibody mAb 35 which labels subunits alpha 1, alpha 3 and alpha 5 in the main immunogenic region of the receptor, visualizes apical dendritic shafts similar to those like bNOS. Strategic localization of bNOS in the primate prefrontal cortex fulfills criteria of producing a freely diffusing retrograde messenger molecule operative in signal transduction routes subserving topography and columnar organization of the cortex, as well as long-term potentiation and long-term depression phenomena underlying mnemonic and gnostic functions. Common occurrence of bNOS and nAChR in identical or similar structures in the prefrontal cortex suggests that interactions between nitrogen oxide and presynaptically released acetylcholine might be involved in the metasynaptic organization of the cerebral cortex, operating in a non-synaptic manner in maintaining optimal performance on cognitive tasks.</p>","PeriodicalId":79356,"journal":{"name":"Neurobiology (Budapest, Hungary)","volume":"6 4","pages":"383-404"},"PeriodicalIF":0.0,"publicationDate":"1998-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21091460","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":"Uneven regional distribution of nucleotide metabolism in human brain.","authors":"Z Kovács,&nbsp;A Dobolyi,&nbsp;T Szikra,&nbsp;M Palkovits,&nbsp;G Juhász","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Adenine and uridine nucleotides and adenosine are proposed to act as neuromodulators and other nucleotides and nucleosides are also suggested to be involved in brain function. A following major step towards the verification of the functional role of nucleotides and nucleosides in the brain would be the examination of regional distribution of purines, pyrimidines and the enzymes involved in their metabolism. Using our recently developed chromatography-based assay for nucleosides from tissue homogenates, we analysed nucleosides in microdissected samples derived from various regions of human brain. Marked differences in the levels of nucleosides were measured in the cerebral cortex, cerebellar cortex, thalamus and white matter. The greatest levels of most nucleosides were found in the cerebral cortex, followed by the cerebellar cortex and the white matter while the smallest concentrations were found in the thalamus, although adenosine and xanthine showed a different distribution pattern in these brain areas. Within the cerebral cortex, the measured substances showed little variations except certain high levels in the cingulate and low levels in the frontal cortex. Even distribution of nucleosides was found in the thalamic nuclei while relative high values were measured in the medial geniculate body. Since a dramatic change in nucleoside concentrations occurs after death, the measured nucleoside concentrations are an interplay of original nucleotide and nucleoside concentrations and enzyme reactions following death. Thus our results suggest regional differences in nucleotide and nucleoside composition and nucleotide metabolising enzyme activities between brain areas.</p>","PeriodicalId":79356,"journal":{"name":"Neurobiology (Budapest, Hungary)","volume":"6 3","pages":"315-21"},"PeriodicalIF":0.0,"publicationDate":"1998-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20690667","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":"Arachidonic acid modulation of [3H]naloxone specific binding to rat brain opioid receptors.","authors":"H A Oktem,&nbsp;S Apaydin","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Arachidonic acid effect on binding of [3H]naloxone to rat brain membranes were studied at opioid receptor subtype level. Arachidonic acid inhibited opioid receptor binding in a dose-dependent manner, both in the presence and absence of sodium. With blockage experiments it was shown that delta-opioid receptors were modulated by arachidonic acid to a greater extent than that of mu-opioid receptors. On the other hand, there was no significant difference in terms of IC50 values for arachidonic acid inhibition of [3H]naloxone binding at agonist and antagonist configuration of the receptor subtypes.</p>","PeriodicalId":79356,"journal":{"name":"Neurobiology (Budapest, Hungary)","volume":"6 3","pages":"323-32"},"PeriodicalIF":0.0,"publicationDate":"1998-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20690668","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}