WorldWideScience

Sample records for cerebral cortex neurons

  1. The Age of Human Cerebral Cortex Neurons

    Energy Technology Data Exchange (ETDEWEB)

    Bhardwaj, R D; Curtis, M A; Spalding, K L; Buchholz, B A; Fink, D; Bjork-Eriksson, T; Nordborg, C; Gage, F H; Druid, H; Eriksson, P S; Frisen, J

    2006-04-06

    The traditional static view of the adult mammalian brain has been challenged by the realization of continuous generation of neurons from stem cells. Based mainly on studies in experimental animals, adult neurogenesis may contribute to recovery after brain insults and decreased neurogenesis has been implicated in the pathogenesis of neurological and psychiatric diseases in man. The extent of neurogenesis in the adult human brain has, however, been difficult to establish. We have taken advantage of the integration of {sup 14}C, generated by nuclear bomb tests during the Cold War, in DNA to establish the age of neurons in the major areas of the human cerebral cortex. Together with the analysis of the cortex from patients who received BrdU, which integrates in the DNA of dividing cells, our results demonstrate that whereas non-neuronal cells turn over, neurons in the human cerebral cortex are not generated postnatally at detectable levels, but are as old as the individual.

  2. The determination of projection neuron identity in the developing cerebral cortex

    OpenAIRE

    Leone, Dino P.; Srinivasan, Karpagam; Chen, Bin; Alcamo, Elizabeth; McConnell, Susan K.

    2008-01-01

    Here we review the mechanisms that determine projection neuron identity during cortical development. Pyramidal neurons in the mammalian cerebral cortex can be classified into two major classes: corticocortical projection neurons, which are concentrated in the upper layers of the cortex, and subcortical projection neurons, which are found in the deep layers. Early progenitor cells in the ventricular zone produce deep layer neurons that express transcription factors including Sox5, Fezf2, and C...

  3. Retinoic acid influences neuronal migration from the ganglionic eminence to the cerebral cortex

    OpenAIRE

    Crandall, James E.; Goodman, Timothy; McCarthy, Deirdre M.; Duester, Gregg; Bhide, Pradeep G.; Dräger, Ursula C.; McCaffery, Peter

    2011-01-01

    The ganglionic eminence contributes cells to several forebrain structures including the cerebral cortex, for which it provides GABAergic interneurons. Migration of neuronal precursors from the retinoic-acid rich embryonic ganglionic eminence to the cerebral cortex is known to be regulated by several factors, but retinoic acid has not been previously implicated. We found retinoic acid to potently inhibit cell migration in slice preparations of embryonic mouse forebrains, which was reversed by ...

  4. Activin A maintains cerebral cortex neuronal survival and increases voltage-gated Na+ neuronal current

    Institute of Scientific and Technical Information of China (English)

    Jingyan Ge; Yinan Wang; Haiyan Liu; Fangfang Chen; Xueling Cui; Zhonghui Liu

    2010-01-01

    Activin A,which was first described in 1986,has been shown to maintain hippocampal neuronal survival.Activin A increases intracellular free Ca2+via L-type Ca2+channels.Our previous study showed that activin A promotes neurite growth of dorsal root ganglia in embryonic chickens and inhibits nitric oxide secretion.The present study demonstrated for the first time that activin A could maintain cerebral cortex neuronal survival in vitro for a tong period,and that activin A was shown to increase voltage-gated Na+current(INa)in Neure-2a cells,which was recorded by patch clamp technique.The present study revealed a novel mechanism for activin A,as well as the influence of activin A on neurons by regulating expressions of vasoactive intestine peptide and inducible nitric oxide synthase.

  5. Directing Astroglia from the Cerebral Cortex into Subtype Specific Functional Neurons

    OpenAIRE

    Christophe Heinrich; Robert Blum; Sergio Gascón; Giacomo Masserdotti; Pratibha Tripathi; Rodrigo Sánchez; Steffen Tiedt; Timm Schroeder; Magdalena Götz; Benedikt Berninger

    2010-01-01

    Astroglia from the postnatal cerebral cortex can be reprogrammed in vitro to generate neurons following forced expression of neurogenic transcription factors, thus opening new avenues towards a potential use of endogenous astroglia for brain repair. However, in previous attempts astroglia-derived neurons failed to establish functional synapses, a severe limitation towards functional neurogenesis. It remained therefore also unknown whether neurons derived from reprogrammed astroglia could be d...

  6. Chandelier neurons within the rabbits' cerebral cortex. A Golgi study.

    Science.gov (United States)

    Müller-Paschinger, I B; Tömböl, T; Petsche, H

    1983-01-01

    This study has been carried out by light microscopy on 3 Golgi-Kopsch impregnated brains of young adult rabbits. It is shown that chandelier cells exist within the rabbits' cerebral cortex. In the rabbit, the chandelier cell is a medium ranged bipolar interneuron in layer II/III with a characteristic axon which forms a plexus with a diameter of about 350-500 micrometers in the horizontal and 200-350 micrometers in the vertical direction; the end of each ramulus forms the typical "candlestick", a little vertical string of 1-6 boutons on an axon fibre. These boutons form contacts with all parts of pyramidal cells in layer II and the upper part of layer III. Similarities and differences with respect to previous descriptions of these cells in other species are discussed. PMID:6837931

  7. Immunohistochemical investigation of neuronal injury in cerebral cortex of cobra-envenomed rats

    OpenAIRE

    T. R. RAHMY; I.A. Hassona

    2004-01-01

    The immunohistochemical expression of neuron-specific enolase, NSE (a cytoplasmic glycolytic enzyme of the neurons), synaptophysin, SYN (a major membrane glycoprotein of synaptic vesicles), and Bcl-2 (anti-apoptotic protein) were determined in cerebral cortex of rats envenomed with neurotoxic venom from Egyptian cobra. Male rats were intramuscularly (IM) injected with a single injection of either physiological saline solution or ½ LD50 or LD50 of cobra venom and sacrificed 24, 48, or 72 hr af...

  8. Sleep-active neuronal nitric oxide synthase-positive cells of the cerebral cortex: a local regulator of sleep?

    OpenAIRE

    Wisor, Jonathan P.; Gerashchenko, Dmitry; Kilduff, Thomas S.

    2011-01-01

    Our recent report demonstrated that a small subset of GABAergic interneurons in the cerebral cortex of rodents expresses Fos protein, a marker for neuronal activity, during slow wave sleep (Gerashchenko et al., 2008). The population of sleep-active neurons consists of strongly immunohistochemically-stained cells for the enzyme neuronal nitric oxide synthase. By virtue of their widespread localization within the cerebral cortex and their widespread projections to other cortical cell types, cor...

  9. BrdU-labelled neurons regeneration after cerebral cortex injury in rats

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yue-lin; QIU Shu-dong; ZHANG Peng-bo; SHI Wei

    2006-01-01

    @@ Mechanical injuries to the external regions of the brain including the cerebral cortex and other parts of the telencephalon are common yet relatively untreatable.1 The predicament in recovery from brain injury is that the adult central nervous system is generally thought to be incapable of replacing dead neurons. As the subventricular zone (SVZ) is now known to be neurogenic and is in close proximity to the cerebral cortex and other functionally important forebrain areas, the neurogeny of SVZ brings hope to the repair of brain injury.2,3 Because of the high frequency of injuries to the cerebral cortex and its functional importance in humans, many laboratories have studied the results of unilateral aspiration or percussion injury of the cerebral cortex.4-6 However,little is known about the response of endogenous neural stem/progenitor cells following loss of the cerebral cortex that commonly occurred in the neurosurgery. We have characterized the time course of the proliferation of neural stem/progenitor cells in the SVZ in brain to loss of cortical cells.

  10. Two separate subtypes of early non-subplate projection neurons in the developing cerebral cortex of rodents

    OpenAIRE

    Ana Espinosa; Cristina Gil-Sanz; Yuchio Yanagawa; Alfonso Fairén

    2009-01-01

    The preplate of the cerebral cortex contains projection neurons that connect the cortical primordium with the subpallium. These are collectively named pioneer neurons. After preplate partition, most of these pioneer neurons become subplate neurons. Certain preplate neurons, however, never associate with the subplate but rather with the marginal zone. In the present overview, we propose a novel classification of non-subplate pioneer neurons in rodents into two subtypes. In rats, the neurons of...

  11. Two Separate Subtypes of Early Non-Subplate Projection Neurons in the Developing Cerebral Cortex of Rodents

    OpenAIRE

    Espinosa, Ana; Gil-Sanz, Cristina; Yanagawa, Yuchio; Fairén, Alfonso

    2009-01-01

    The preplate of the cerebral cortex contains projection neurons that connect the cortical primordium with the subpallium. These are collectively named pioneer neurons. After preplate partition, most of these pioneer neurons become subplate neurons. Certain preplate neurons, however, never associate with the subplate but rather with the marginal zone. In the present overview, we propose a novel classification of non-subplate pioneer neurons in rodents into two subtypes. In rats, the neurons of...

  12. Directing astroglia from the cerebral cortex into subtype specific functional neurons.

    Directory of Open Access Journals (Sweden)

    Christophe Heinrich

    2010-05-01

    Full Text Available Astroglia from the postnatal cerebral cortex can be reprogrammed in vitro to generate neurons following forced expression of neurogenic transcription factors, thus opening new avenues towards a potential use of endogenous astroglia for brain repair. However, in previous attempts astroglia-derived neurons failed to establish functional synapses, a severe limitation towards functional neurogenesis. It remained therefore also unknown whether neurons derived from reprogrammed astroglia could be directed towards distinct neuronal subtype identities by selective expression of distinct neurogenic fate determinants. Here we show that strong and persistent expression of neurogenic fate determinants driven by silencing-resistant retroviral vectors instructs astroglia from the postnatal cortex in vitro to mature into fully functional, synapse-forming neurons. Importantly, the neurotransmitter fate choice of astroglia-derived neurons can be controlled by selective expression of distinct neurogenic transcription factors: forced expression of the dorsal telencephalic fate determinant neurogenin-2 (Neurog2 directs cortical astroglia to generate synapse-forming glutamatergic neurons; in contrast, the ventral telencephalic fate determinant Dlx2 induces a GABAergic identity, although the overall efficiency of Dlx2-mediated neuronal reprogramming is much lower compared to Neurog2, suggesting that cortical astroglia possess a higher competence to respond to the dorsal telencephalic fate determinant. Interestingly, however, reprogramming of astroglia towards the generation of GABAergic neurons was greatly facilitated when the astroglial cells were first expanded as neurosphere cells prior to transduction with Dlx2. Importantly, this approach of expansion under neurosphere conditions and subsequent reprogramming with distinct neurogenic transcription factors can also be extended to reactive astroglia isolated from the adult injured cerebral cortex, allowing for the

  13. APP Metabolism Regulates Tau Proteostasis in Human Cerebral Cortex Neurons

    Directory of Open Access Journals (Sweden)

    Steven Moore

    2015-05-01

    Full Text Available Accumulation of Aβ peptide fragments of the APP protein and neurofibrillary tangles of the microtubule-associated protein tau are the cellular hallmarks of Alzheimer’s disease (AD. To investigate the relationship between APP metabolism and tau protein levels and phosphorylation, we studied human-stem-cell-derived forebrain neurons with genetic forms of AD, all of which increase the release of pathogenic Aβ peptides. We identified marked increases in intracellular tau in genetic forms of AD that either mutated APP or increased its dosage, suggesting that APP metabolism is coupled to changes in tau proteostasis. Manipulating APP metabolism by β-secretase and γ-secretase inhibition, as well as γ-secretase modulation, results in specific increases and decreases in tau protein levels. These data demonstrate that APP metabolism regulates tau proteostasis and suggest that the relationship between APP processing and tau is not mediated solely through extracellular Aβ signaling to neurons.

  14. Both Myosin-10 isoforms are required for radial neuronal migration in the developing cerebral cortex.

    Science.gov (United States)

    Ju, Xing-Da; Guo, Ye; Wang, Nan-Nan; Huang, Ying; Lai, Ming-Ming; Zhai, Yan-Hua; Guo, Yu-Guang; Zhang, Jian-Hua; Cao, Rang-Juan; Yu, Hua-Li; Cui, Lei; Li, Yu-Ting; Wang, Xing-Zhi; Ding, Yu-Qiang; Zhu, Xiao-Juan

    2014-05-01

    During embryonic development of the mammalian cerebral cortex, postmitotic cortical neurons migrate radially from the ventricular zone to the cortical plate. Proper migration involves the correct orientation of migrating neurons and the transition from a multipolar to a mature bipolar morphology. Herein, we report that the 2 isoforms of Myosin-10 (Myo10) play distinct roles in the regulation of radial migration in the mouse cortex. We show that the full-length Myo10 (fMyo10) isoform is located in deeper layers of the cortex and is involved in establishing proper migration orientation. We also demonstrate that fMyo10-dependent orientation of radial migration is mediated at least in part by the netrin-1 receptor deleted in colorectal cancer. Moreover, we show that the headless Myo10 (hMyo10) isoform is required for the transition from multipolar to bipolar morphologies in the intermediate zone. Our study reveals divergent functions for the 2 Myo10 isoforms in controlling both the direction of migration and neuronal morphogenesis during radial cortical neuronal migration. PMID:23300110

  15. Effect of Magnesium on Nitric Oxide Synthase of Neurons in Cortex during Early Period of Cerebral Ischemia

    Institute of Scientific and Technical Information of China (English)

    SUN Xiu; MEI Yuanwu; TONG E'tang

    2000-01-01

    To investigate the effect of magnesium on nitric oxide synthase (NOS) of neurons in cortex during early cerebral ischemic period, a rat model of middle cerebral artery occlusion (MCAO) was established. The results showed that the NOS activity of neurons in cortex was increased significantly at 15 min after MCAO, reached its peak at 30 min after MCAO and returned to normal levels at 60 min after MCAO. The NOS activity of neurons in the magnesium-treated group was decreased significantly as compared with that in the ischemic group at 15 min and 30min after MCAO respectively. The results suggested that magnesium could inhibit the elevated NOS activity of neurons in cortex induced by cerebral ischemia.

  16. RP58 Regulates the Multipolar-Bipolar Transition of Newborn Neurons in the Developing Cerebral Cortex

    Directory of Open Access Journals (Sweden)

    Chiaki Ohtaka-Maruyama

    2013-02-01

    Full Text Available Accumulating evidence suggests that many brain diseases are associated with defects in neuronal migration, suggesting that this step of neurogenesis is critical for brain organization. However, the molecular mechanisms underlying neuronal migration remain largely unknown. Here, we identified the zinc-finger transcriptional repressor RP58 as a key regulator of neuronal migration via multipolar-to-bipolar transition. RP58−/− neurons exhibited severe defects in the formation of leading processes and never shifted to the locomotion mode. Cre-mediated deletion of RP58 using in utero electroporation in RP58flox/flox mice revealed that RP58 functions in cell-autonomous multipolar-to-bipolar transition, independent of cell-cycle exit. Finally, we found that RP58 represses Ngn2 transcription to regulate the Ngn2-Rnd2 pathway; Ngn2 knockdown rescued migration defects of the RP58−/− neurons. Our findings highlight the critical role of RP58 in multipolar-to-bipolar transition via suppression of the Ngn2-Rnd2 pathway in the developing cerebral cortex.

  17. Molecular Regulation of DNA Damage-Induced Apoptosis in Neurons of Cerebral Cortex

    OpenAIRE

    Martin, Lee J.; Liu, Zhiping; Pipino, Jacqueline; Chestnut, Barry; Landek, Melissa A.

    2008-01-01

    Cerebral cortical neuron degeneration occurs in brain disorders manifesting throughout life, but the mechanisms are understood poorly. We used cultured embryonic mouse cortical neurons and an in vivo mouse model to study mechanisms of DNA damaged-induced apoptosis in immature and differentiated neurons. p53 drives apoptosis of immature and differentiated cortical neurons through its rapid and prominent activation stimulated by DNA strand breaks induced by topoisomerase-I and -II inhibition. B...

  18. Evolutionary appearance of von Economo’s neurons in the mammalian cerebral cortex

    OpenAIRE

    Alessandro Vercelli

    2014-01-01

    von Economo’s neurons (VENs) are large, spindle-shaped projection neurons in layer V of the frontoinsular (FI) cortex, and the anterior cingulate cortex. During human ontogenesis, the VENs can first be differentiated at late stages of gestation, and increase in number during the first eight postnatal months. VENs have been identified in humans, chimpanzee, bonobos, gorillas, orangutan and, more recently, in the macaque. Their distribution in great apes seems to correlate with human-like socia...

  19. The Fezf2–Ctip2 genetic pathway regulates the fate choice of subcortical projection neurons in the developing cerebral cortex

    OpenAIRE

    Chen, Bin; Wang, Song S.; HATTOX, ALEXIS M.; Rayburn, Helen; Nelson, Sacha B.; McConnell, Susan K.

    2008-01-01

    Pyramidal neurons in the deep layers of the cerebral cortex can be classified into two major classes: callosal projection neurons and long-range subcortical neurons. We and others have shown that a gene expressed specifically by subcortical projection neurons, Fezf2, is required for the formation of axonal projections to the spinal cord, tectum, and pons. Here, we report that Fezf2 regulates a decision between subcortical vs. callosal projection neuron fates. Fezf2−/− neurons adopt the fate o...

  20. Cdk5-mediated phosphorylation of RapGEF2 controls neuronal migration in the developing cerebral cortex.

    Science.gov (United States)

    Ye, Tao; Ip, Jacque P K; Fu, Amy K Y; Ip, Nancy Y

    2014-01-01

    During cerebral cortex development, pyramidal neurons migrate through the intermediate zone and integrate into the cortical plate. These neurons undergo the multipolar-bipolar transition to initiate radial migration. While perturbation of this polarity acquisition leads to cortical malformations, how this process is initiated and regulated is largely unknown. Here we report that the specific upregulation of the Rap1 guanine nucleotide exchange factor, RapGEF2, in migrating neurons corresponds to the timing of this polarity transition. In utero electroporation and live-imaging studies reveal that RapGEF2 acts on the multipolar-bipolar transition during neuronal migration via a Rap1/N-cadherin pathway. Importantly, activation of RapGEF2 is controlled via phosphorylation by a serine/threonine kinase Cdk5, whose activity is largely restricted to the radial migration zone. Thus, the specific expression and Cdk5-dependent phosphorylation of RapGEF2 during multipolar-bipolar transition within the intermediate zone are essential for proper neuronal migration and wiring of the cerebral cortex. PMID:25189171

  1. Selective reduction of cerebral cortex GABA neurons in a late gestation model of fetal alcohol spectrum disorder.

    Science.gov (United States)

    Smiley, John F; Saito, Mariko; Bleiwas, Cynthia; Masiello, Kurt; Ardekani, Babak; Guilfoyle, David N; Gerum, Scott; Wilson, Donald A; Vadasz, Csaba

    2015-09-01

    Fetal alcohol spectrum disorders (FASD) are associated with cognitive and behavioral deficits, and decreased volume of the whole brain and cerebral cortex. Rodent models have shown that early postnatal treatments, which mimic ethanol toxicity in the third trimester of human pregnancy, acutely induce widespread apoptotic neuronal degeneration and permanent behavioral deficits. However, the lasting cellular and anatomical effects of early ethanol treatments are still incompletely understood. This study examined changes in neocortex volume, thickness, and cellular organization that persist in adult mice after postnatal day 7 (P7) ethanol treatment. Post mortem brain volumes, measured by both MRI within the skull and by fluid displacement of isolated brains, were reduced 10-13% by ethanol treatment. The cerebral cortex showed a similar reduction (12%) caused mainly by lower surface area (9%). In spite of these large changes, several features of cortical organization showed little evidence of change, including cortical thickness, overall neuron size, and laminar organization. Estimates of total neuron number showed a trend level reduction of about 8%, due mainly to reduced cortical volume but unchanged neuron density. However, counts of calretinin (CR) and parvalbumin (PV) subtypes of GABAergic neurons showed a striking >30% reduction of neuron number. Similar ethanol effects were found in male and female mice, and in C57BL/6By and BALB/cJ mouse strains. Our findings indicate that the cortex has substantial capacity to develop normal cytoarchitectonic organization after early postnatal ethanol toxicity, but there is a selective and persistent reduction of GABA cells that may contribute to the lasting cognitive and behavioral deficits in FASD.

  2. MicroRNA function is required for neurite outgrowth of mature neurons in the mouse postnatal cerebral cortex

    Directory of Open Access Journals (Sweden)

    Janet eHong

    2013-09-01

    Full Text Available The structure of the postnatal mammalian cerebral cortex is an assembly of numerous mature neurons that exhibit proper neurite outgrowth and axonal and dendritic morphology. While many protein coding genes are shown to be involved in neuronal maturation, the role of microRNAs (miRNAs in this process is also becoming evident. We here report that blocking miRNA biogenesis in differentiated neurons results in microcephaly-like phenotypes in the postnatal mouse brain. The smaller brain defect is not caused by defective neurogenesis, altered neuronal migration or significant neuronal cell death. Surprisingly, a dramatic increase in neuronal packing density within the postnatal brain is observed. Loss of miRNA function causes shorter neurite outgrowth and smaller soma size of mature neurons in vitro. Our results reveal the impact of miRNAs on normal development of neuronal morphology and brain function. Because neurite outgrowth is critical for neuroregeneration, our studies further highlight the importance of miRNAs in the treatment of neurodegenerative diseases.

  3. Correlations between histology and neuronal activity recorded by microelectrodes implanted chronically in the cerebral cortex

    Science.gov (United States)

    McCreery, Douglas; Cogan, Stuart; Kane, Sheryl; Pikov, Victor

    2016-06-01

    Objective. To quantify relations between the neuronal activity recorded with chronically-implanted intracortical microelectrodes and the histology of the surrounding tissue, using radial distance from the tip sites and time after array implantation as parameters. Approach. ‘Utah’-type intracortical microelectrode arrays were implanted into cats’ sensorimotor cortex for 275-364 days. The brain tissue around the implants was immuno-stained for the neuronal marker NeuN and for the astrocyte marker GFAP. Pearson’s product-moment correlations were used to quantify the relations between these markers and the amplitudes of the recorded neuronal action potentials (APs) and their signal-to-noise ratios (S/N). Main results. S/N was more stable over post-implant time than was AP amplitude, but its increased correlation with neuronal density after many months indicates ongoing loss of neurons around the microelectrodes. S/N was correlated with neuron density out to at least 140 μm from the microelectrodes, while AP amplitude was correlated with neuron density and GFAP density within ˜80 μm. Correlations between AP amplitude and histology markers (GFAP and NeuN density) were strongest immediately after implantation, while correlation between the neuron density and S/N was strongest near the time the animals were sacrificed. Unlike AP amplitude, there was no significant correlation between S/N and density of GFAP around the tip sites. Significance. Our findings indicate an evolving interaction between changes in the tissue surrounding the microelectrodes and the microelectrode’s electrical properties. Ongoing loss of neurons around recording microelectrodes, and the interactions between their delayed electrical deterioration and early tissue scarring around the tips appear to pose the greatest threats to the microelectrodes’ long-term functionality.

  4. An analysis of von Economo neurons in the cerebral cortex of cetaceans, artiodactyls, and perissodactyls.

    Science.gov (United States)

    Raghanti, Mary Ann; Spurlock, Linda B; Treichler, F Robert; Weigel, Sara E; Stimmelmayr, Raphaela; Butti, Camilla; Thewissen, J G M Hans; Hof, Patrick R

    2015-07-01

    Von Economo neurons (VENs) are specialized projection neurons with a characteristic spindle-shaped soma and thick basal and apical dendrites. VENs have been described in restricted cortical regions, with their most frequent appearance in layers III and V of the anterior cingulate cortex, anterior insula, and frontopolar cortex of humans, great apes, macaque monkeys, elephants, and some cetaceans. Recently, a ubiquitous distribution of VENs was reported in various cortical areas in the pygmy hippopotamus, one of the closest living relatives of cetaceans. That finding suggested that VENs might not be unique to only a few species that possess enlarged brains. In the present analysis, we assessed the phylogenetic distribution of VENs within species representative of the superordinal clade that includes cetartiodactyls and perissodactyls, as well as afrotherians. In addition, the distribution of fork cells that are often found in close proximity to VENs was also assessed. Nissl-stained sections from the frontal pole, anterior cingulate cortex, anterior insula, and occipital pole of bowhead whale, cow, sheep, deer, horse, pig, rock hyrax, and human were examined using stereologic methods to quantify VENs and fork cells within layer V of all four cortical regions. VENs and fork cells were found in each of the species examined here with species-specific differences in distributions and densities. The present results demonstrated that VENs and fork cells were not restricted to highly encephalized or socially complex species, and their repeated emergence among distantly related species seems to represent convergent evolution of specialized pyramidal neurons. The widespread phylogenetic presence of VENs and fork cells indicates that these neuron morphologies readily emerged in response to selective forces,whose variety and nature are yet to be identified.

  5. LPS-induced microglial secretion of TNFα increases activity-dependent neuronal apoptosis in the neonatal cerebral cortex.

    Science.gov (United States)

    Nimmervoll, Birgit; White, Robin; Yang, Jenq-Wei; An, Shuming; Henn, Christopher; Sun, Jyh-Jang; Luhmann, Heiko J

    2013-07-01

    During the pre- and neonatal period, the cerebral cortex reveals distinct patterns of spontaneous synchronized activity, which is critically involved in the formation of early networks and in the regulation of neuronal survival and programmed cell death (apoptosis). During this period, the cortex is also highly vulnerable to inflammation and in humans prenatal infection may have a profound impact on neurodevelopment causing long-term neurological deficits. Using in vitro and in vivo multi-electrode array recordings and quantification of caspase-3 (casp-3)-dependent apoptosis, we demonstrate that lipopolysaccharide-induced inflammation causes rapid alterations in the pattern of spontaneous burst activities, which subsequently leads to an increase in apoptosis. We show that these inflammatory effects are specifically initiated by the microglia-derived pro-inflammatory cytokine tumor necrosis factor α and the chemokine macrophage inflammatory protein 2. Our data demonstrate that inflammation-induced modifications in spontaneous network activities influence casp-3-dependent cell death in the developing cerebral cortex.

  6. Cholinergic Neurons - Keeping Check on Amyloid beta in the Cerebral Cortex

    Directory of Open Access Journals (Sweden)

    Saak V. Ovsepian

    2013-12-01

    Full Text Available The physiological relevance of the uptake of ligands with no apparent trophic functions via the p75 neurotrophin receptor (p75NTR remains unclear. Herein, we propose a homeostatic role for this in clearance of amyloid β (Aβ in the brain. We hypothesize that uptake of Aβ in conjunction with p75NTR followed by its degradation in lysosomes endows cholinergic basalo-cortical projections enriched in this receptor a facility for maintaining physiological levels of Aβ in target areas. Thus, in addition to the diffuse modulator influence and channeling of extra-thalamic signals, cholinergic innervations could supply the cerebral cortex with an elaborate system for Aβ drainage. Interpreting the emerging relationship of new molecular data with established role of cholinergic modulator system in regulating cortical network dynamics should provide new insights into the brain physiology and mechanisms of neuro-degenerative diseases.

  7. Greater addition of neurons to the olfactory bulb than to the cerebral cortex of eulipotyphlans but not rodents, afrotherians or primates

    Directory of Open Access Journals (Sweden)

    Pedro Furtado De Mattos Ribeiro

    2014-04-01

    Full Text Available The olfactory bulb is an evolutionarily old structure that antedates the appearance of a six-layered mammalian cerebral cortex. As such, the neuronal scaling rules that apply to scaling the mass of the olfactory bulb as a function of its number of neurons might be shared across mammalian groups, as we have found to be the case for the ensemble of non-cortical, non-cerebellar brain structures. Alternatively, the neuronal scaling rules that apply to the olfactory bulb might be distinct in those mammals that rely heavily on olfaction. The group previously referred to as Insectivora includes small mammals, some of which are now placed in Afrotheria, a base group in mammalian radiation, and others in Eulipotyphla, a group derived later, at the base of Laurasitheria. Here we show that the neuronal scaling rules that apply to building the olfactory bulb differ across eulipotyphlans and other mammals such that eulipotyphlans have more neurons concentrated in an olfactory bulb of similar size than afrotherians, glires and primates. Most strikingly, while the cerebral cortex gains neurons at a faster pace than the olfactory bulb in glires, and afrotherians follow this trend, it is the olfactory bulb that gains neurons at a faster pace than the cerebral cortex in eulipotyphlans, which contradicts the common view that the cerebral cortex is the fastest expanding structure in brain evolution. Our findings emphasize the importance of not using brain structure size as a proxy for numbers of neurons across mammalian orders, and are consistent with the notion that different selective pressures have acted upon the olfactory system of eulipotyphlans, glires and primates, with eulipotyphlans relying more on olfaction for their behavior than glires and primates. Surprisingly, however, the neuronal scaling rules for primates predict that the human olfactory bulb has as many neurons as the larger eulipotyphlan olfactory bulbs, which questions the classification of

  8. [Postsynaptic reactions of cerebral cortex neurons, activated by nociceptive afferents during stimulation of the Raphe nuclei].

    Science.gov (United States)

    Labakhua, T Sh; Dzhanashiia, T K; Gedevanishvili, G I; Dzhokhadze, L D; Tkemaladze, T T; Abzianidze, I V

    2012-01-01

    On cats, we studied the influence of stimulation of the Raphe nuclei (RN) on postsynaptic processes evoked in neurons of the somatosensory cortex by stimulation of nociceptive (intensive stimulation of the tooth pulp) and non-nociceptive (moderate stimulation of the ventroposteromedial--VPN--nucleus of the thalamus) afferent inputs. 6 cells, selectively excited by stimulation of nocciceptors and 9 cells, activated by both the above nociceptive and non-nociceptive influences (nociceptive and convergent neurons, respectively) were recorded intracellular. In neurons of both groups, responses to nociceptive stimulation (of sufficient intensity) looked like an EPSP-spike-IPSP (the letter of significant duration, up to 200-300 ms) compleх. Conditioning stimulation of the RN which preceded test stimulus applied to the tooth pulp or VPM nucleus by 100 to 800 ms, induced 40-60 % decrease of the IPSP amplitude only, while maхimal effect of influence, in both cases, was noted within intervals of 300-800 ms between conditioning and test stimulus. During stimulation of the RN, serotonin released via receptor and second messengers, provides postsynaptic modulation of GABAergic system, decreasing the IPSP amplitude which occurs after stimulation of both the tooth pulp and VPM thalamic nucleus. This process may be realized trough either pre- or postsynaptic mechanisms.

  9. Evolutionary appearance of von Economo's neurons in the mammalian cerebral cortex.

    Science.gov (United States)

    Cauda, Franco; Geminiani, Giuliano Carlo; Vercelli, Alessandro

    2014-01-01

    von Economo's neurons (VENs) are large, spindle-shaped projection neurons in layer V of the frontoinsular (FI) cortex, and the anterior cingulate cortex. During human ontogenesis, the VENs can first be differentiated at late stages of gestation, and increase in number during the first eight postnatal months. VENs have been identified in humans, chimpanzee, bonobos, gorillas, orangutan and, more recently, in the macaque. Their distribution in great apes seems to correlate with human-like social cognitive abilities and self-awareness. VENs are also found in whales, in a number of different cetaceans, and in the elephant. This phylogenetic distribution may suggest a correlation among the VENs, brain size and the "social brain." VENs may be involved in the pathogenesis of specific neurological and psychiatric diseases, such as autism, callosal agenesis and schizophrenia. VENs are selectively affected in a behavioral variant of frontotemporal dementia in which empathy, social awareness and self-control are seriously compromised, thus associating VENs with the social brain. However, the presence of VENs has also been related to special functions such as mirror self-recognition. Areas containing VENs have been related to motor awareness or sense-of-knowing, discrimination between self and other, and between self and the external environment. Along this line, VENs have been related to the "global Workspace" architecture: in accordance the VENs have been correlated to emotional and interoceptive signals by providing fast connections (large axons = fast communication) between salience-related insular and cingulate and other widely separated brain areas. Nevertheless, the lack of a characterization of their physiology and anatomical connectivity allowed only to infer their functional role based on their location and on the functional magnetic resonance imaging data. The recent finding of VENs in the anterior insula of the macaque opens the way to new insights and experimental

  10. Evolutionary appearance of Von Economo’s Neurons in the mammalian cerebral cortex

    Directory of Open Access Journals (Sweden)

    Franco eCauda

    2014-03-01

    Full Text Available Von Economo’s neurons (VENs are large, spindle-shaped projection neurons in layer V of the frontoinsular (FI cortex, and the anterior cingulate cortex. During human ontogenesis, the VENs can first be differentiated at late stages of gestation, and increase in number during the first eight postnatal months.VENs have been identified in humans, chimpanzee, bonobos, gorillas, orangutan and, more recently, in the macaque. Their distribution in great apes seems to correlate with human-like social cognitive abilities and self-awareness. VENs are also found in whales, in a number of different cetaceans, and in the elephant. This phylogenetic distribution may suggest a correlation among the VENs, brain size and the social brain. VENs may be involved in the pathogenesis of specific neurological and psychiatric diseases, such as autism, callosal agenesis and schizophrenia. VENs are selectively affected in a behavioral variant of frontotemporal dementia in which empathy, social awareness and self-control are seriously compromised, thus associating VENs with the social brain.However, the presence of VENs has also been related to special functions such as mirror self-recognition. Areas containing VENs have been related to motor awareness or sense-of-knowing, discrimination between self and other, and between self and the external environment. Along this line, VENs have been related to the global Workspace architecture: in accordance the VENs have been correlated to emotional and interoceptive signals by providing fast connections (large axons = fast communication between salience-related insular and cingulate and other widely separated brain areas.Nevertheless, the lack of a characterization of their physiology and anatomical connectivity allowed only to infer their functional role based on their location and on the fMRI data. The recent finding of VENs in the anterior insula of the macaque opens the way to new insights and experimental investigatio

  11. ADAM17 is critical for multipolar exit and radial migration of neuronal intermediate progenitor cells in mice cerebral cortex.

    Directory of Open Access Journals (Sweden)

    Qingyu Li

    Full Text Available The radial migration of neuronal progenitor cells is critical for the development of cerebral cortex layers. They go through a critical step transforming from multipolar to bipolar before outward migration. A Disintegrin and Metalloprotease 17 (ADAM17 is a transmembrane protease which can process many substrates involved in cell-cell interaction, including Notch, ligands of EGFR, and some cell adhesion molecules. In this study, we used in utero electroporation to knock down or overexpress ADAM17 at embryonic day 14.5 (E14.5 in neuronal progenitor cells to examine the role of ADAM17 in cortical embryonic neurogenesis. Our results showed that the radial migration of ADAM17-knocked down cells were normal till E16.5 and reached the intermediate zone (IZ. Then most transfected cells stopped migration and stayed at the IZ to inner cortical plate (CP layer at E18.5, and there was higher percentage of multipolar cells at IZ layer in the ADAM17-knocked down group compared to the cells in control group. Marker staining revealed that those ADAM17-knocked down cells differentiated normally from neural stem cells (NSCs to neuronal intermediate progenitor cells (nIPCs but did not differentiate into mature neurons. The migration and multipolar exit defects caused by ADAM17 knockdown could be partially rescued by over-expressing an shRNA resistant ADAM17, while overexpressing ADAM17 alone did not affect the radial migration. Taken together, our results showed for the first time that, ADAM17 is critical in regulating the multipolar-stage exit and radial migration of the nIPCs during telencephalon cortex development in mice.

  12. ADAM17 is critical for multipolar exit and radial migration of neuronal intermediate progenitor cells in mice cerebral cortex.

    Science.gov (United States)

    Li, Qingyu; Zhang, Zhengyu; Li, Zengmin; Zhou, Mei; Liu, Bin; Pan, Le; Ma, Zhixing; Zheng, Yufang

    2013-01-01

    The radial migration of neuronal progenitor cells is critical for the development of cerebral cortex layers. They go through a critical step transforming from multipolar to bipolar before outward migration. A Disintegrin and Metalloprotease 17 (ADAM17) is a transmembrane protease which can process many substrates involved in cell-cell interaction, including Notch, ligands of EGFR, and some cell adhesion molecules. In this study, we used in utero electroporation to knock down or overexpress ADAM17 at embryonic day 14.5 (E14.5) in neuronal progenitor cells to examine the role of ADAM17 in cortical embryonic neurogenesis. Our results showed that the radial migration of ADAM17-knocked down cells were normal till E16.5 and reached the intermediate zone (IZ). Then most transfected cells stopped migration and stayed at the IZ to inner cortical plate (CP) layer at E18.5, and there was higher percentage of multipolar cells at IZ layer in the ADAM17-knocked down group compared to the cells in control group. Marker staining revealed that those ADAM17-knocked down cells differentiated normally from neural stem cells (NSCs) to neuronal intermediate progenitor cells (nIPCs) but did not differentiate into mature neurons. The migration and multipolar exit defects caused by ADAM17 knockdown could be partially rescued by over-expressing an shRNA resistant ADAM17, while overexpressing ADAM17 alone did not affect the radial migration. Taken together, our results showed for the first time that, ADAM17 is critical in regulating the multipolar-stage exit and radial migration of the nIPCs during telencephalon cortex development in mice. PMID:23755270

  13. Morphological properties of nociceptive and non-nociceptive neurons in primary somatic cerebral cortex (SI) of cat

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    With the techniques of intracellular recording and labelling, we investigated pain sensation and modulation of the somatic cortical cortex at the neuron's level. After observing the evoked potentials from stimulating the saphenous nerves (SN) of 654 neurons in SI area of the cats, we labelled 30 of the neurons with Neurobiotin to preserve the distribution and the morphologic characteristics of the neurons in the cortex. Based on the tridimensional reconstruction in addition to the eletrophysiological functions, we found clear morphological distinctions between nociceptive and non-nociceptive neurons (P<0.01). This result provided new experimental material to illustrate the function of nociceptive neurons in somatosensory cortex (SI) and presented further evidence to support the "specificity theory" of pain sensation in terms of morphology.

  14. Greater addition of neurons to the olfactory bulb than to the cerebral cortex of eulipotyphlans but not rodents, afrotherians or primates

    OpenAIRE

    Ribeiro, Pedro F. M.; Manger, Paul R.; Catania, Kenneth C.; Kaas, Jon H.; Herculano-Houzel, Suzana

    2014-01-01

    The olfactory bulb is an evolutionarily old structure that antedates the appearance of a six-layered mammalian cerebral cortex. As such, the neuronal scaling rules that apply to scaling the mass of the olfactory bulb as a function of its number of neurons might be shared across mammalian groups, as we have found to be the case for the ensemble of non-cortical, non-cerebellar brain structures. Alternatively, the neuronal scaling rules that apply to the olfactory bulb might be distinct in those...

  15. Ablation of the 14-3-3gamma Protein Results in Neuronal Migration Delay and Morphological Defects in the Developing Cerebral Cortex.

    Science.gov (United States)

    Wachi, Tomoka; Cornell, Brett; Marshall, Courtney; Zhukarev, Vladimir; Baas, Peter W; Toyo-oka, Kazuhito

    2016-06-01

    14-3-3 proteins are ubiquitously-expressed and multifunctional proteins. There are seven isoforms in mammals with a high level of homology, suggesting potential functional redundancy. We previously found that two of seven isoforms, 14-3-3epsilon and 14-3-3zeta, are important for brain development, in particular, radial migration of pyramidal neurons in the developing cerebral cortex. In this work, we analyzed the function of another isoform, the protein 14-3-3gamma, with respect to neuronal migration in the developing cortex. We found that in utero 14-3-3gamma-deficiency resulted in delays in neuronal migration as well as morphological defects. Migrating neurons deficient in 14-3-3gamma displayed a thicker leading process stem, and the basal ends of neurons were not able to reach the boundary between the cortical plate and the marginal zone. Consistent with the results obtained from in utero electroporation, time-lapse live imaging of brain slices revealed that the ablation of the 14-3-3gamma proteins in pyramidal neurons slowed down their migration. In addition, the 14-3-3gamma deficient neurons showed morphological abnormalities, including increased multipolar neurons with a thicker leading processes stem during migration. These results indicate that the 14-3-3gamma proteins play an important role in radial migration by regulating the morphology of migrating neurons in the cerebral cortex. The findings underscore the pathological phenotypes of brain development associated with the disruption of different 14-3-3 proteins and will advance the preclinical data regarding disorders caused by neuronal migration defects.

  16. Expression of c-Fos protein and nitricoxide synthase in neurons of cerebral cortex from fetal rats in hypoxia and protective role of Angelica sinensis

    Institute of Scientific and Technical Information of China (English)

    Hong Yu; Hongxian Zhao; Yuling Wu

    2006-01-01

    BACKGROUND: Both c-Fos protein and nitricoxide synthase (NOS) have been used as general indexes in relative research about neurons, but it is lack of reports that c-Fos protein and NOS are applied synchronously to study the neurons of hypoxic fetal rats in uterus.OBJECTIVE: To study the effect of hypoxia in uterus on the expression of c-Fos protein and NOS in neurons of cerebral cortex from fetal rats and whether Angelica sinensis has the protective effect on these neurons in hypoxia.DESIGN: Randomized control experiment.SETTING: Department of Histology and Embryology, Luzhou Medical College.MATERIALS: Twelve adult female Wistar rats in oestrum and 1 male Wistar rat with bodymass from 220 to 250 g were chosen. Parenteral solution of Angelica sinensis mainly contained angelica sinensis, 10 mL/ampoule, was provided by Department of Agent of the Second Hospital Affiliated to Hubei Medical University (batch number: 01062310).METHODS: This experiment was completed in the Department of Histology and Embryology of Luzhou Medical College from September 2003 to June 2004. ① Twelve adult female Wistar rats in oestrum and 1 male Wistar rat were housed in one rearing cage. Vaginal embolus was performed on conceive female rat at 8:00 am next day.On the 15th conceiving day,all conceiving rats were divided randomly into three groups:control group, hypoxia group and Angelica group with 4 in each group. Rats in hypoxia group and Angelica group were modeled with hypotonic hypoxia in uterus. Angelica group: Rats were injected with 8 mL/kg Angelica sinensis injection through caudal veins before hypoxia.Hypoxia group:Rats were injected with the same volume of saline.Control group:Rats were not modeled and fed with normal way. ② Twenty embryos of rats were chosen randomly from each group and then routinely embedded in paraffin. Paraffin sections were cut from the brain of embryos to anterior fontanelle. Double-label staining was used to detect the expression of nNOS and c-Fos in

  17. Diffusion tensor imaging detects early cerebral cortex abnormalities in neuronal architecture induced by bilateral neonatal enucleation: An experimental model in the ferret

    Directory of Open Access Journals (Sweden)

    Andrew S Bock

    2010-10-01

    Full Text Available Diffusion tensor imaging (DTI is a technique that non-invasively provides quantitative measures of water translational diffusion, including fractional anisotropy (FA, that are sensitive to the shape and orientation of cellular elements, such as axons, dendrites and cell somas. For several neurodevelopmental disorders, histopathological investigations have identified abnormalities in the architecture of pyramidal neurons at early stages of cerebral cortex development. To assess the potential capability of DTI to detect neuromorphological abnormalities within the developing cerebral cortex, we compare changes in cortical FA with changes in neuronal architecture and connectivity induced by bilateral enucleation at postnatal day 7 (BEP7 in ferrets. We show here that the visual callosal pattern in BEP7 ferrets is more irregular and occupies a significantly greater cortical area compared to controls at adulthood. To determine whether development of the cerebral cortex is altered in BEP7 ferrets in a manner detectable by DTI, cortical FA was compared in control and BEP7 animals on postnatal day 31. Visual cortex, but not rostrally-adjacent non-visual cortex, exhibits higher FA than control animals, consistent with BEP7 animals possessing axonal and dendritic arbors of reduced complexity than age-matched controls. Subsequent to DTI, Golgi staining and analysis methods were used to identify regions, restricted to visual areas, in which the orientation distribution of neuronal processes is significantly more concentrated than in control ferrets. Together, these findings suggest that DTI can be of utility for detecting abnormalities associated with neurodevelopmental disorders at early stages of cerebral cortical development, and that the neonatally-enucleated ferret is a useful animal model system for systematically assessing the potential of this new diagnostic strategy.

  18. Subplate cells: amplifiers of neuronal activity in the developing cerebral cortex

    Directory of Open Access Journals (Sweden)

    Heiko J Luhmann

    2009-10-01

    Full Text Available Due to their unique structural and functional properties, subplate cells are ideally suited to function as important amplifying units within the developing neocortical circuit. Subplate neurons have extensive dendritic and axonal ramifications and relatively mature functional properties, i.e. their action potential firing can exceed frequencies of 40 Hz. At earliest stages of corticogenesis subplate cells receive functional synaptic inputs from the thalamus and from other cortical and non-cortical sources. Glutamatergic and depolarizing GABAergic inputs arise from cortical neurons and neuromodulatory inputs arise from the basal forebrain and other sources. Activation of postsynaptic metabotropic receptors, i.e. muscarinic receptors, elicits in subplate neurons oscillatory burst discharges which are transmitted via electrical and chemical synapses to neighbouring subplate cells and to immature neurons in the cortical plate. The tonic nonsynaptic release of GABA from GABAergic subplate cells facilitates the generation of burst discharges. These cellular bursts are amplified by prominent gap junction coupling in the subplate and cortical plate, thereby eliciting 10 to 20 Hz oscillations in a local columnar network. Thus, we propose that neuronal networks are organized at earliest stages in a gap junction coupled columnar syncytium. We postulate that the subplate does not only serve as a transient relay station for afferent inputs, but rather as an active element amplifying the afferent and intracortical activity.

  19. Output of Neurogliaform Cells to Various Neuron Types in the Human and Rat Cerebral Cortex

    OpenAIRE

    Oláh, Szabolcs; Komlósi, Gergely; Szabadics, János; Varga, Csaba; Tóth, Éva; Barzó, Pál; Tamás, Gábor

    2007-01-01

    Neurogliaform cells in the rat elicit combined GABAA and GABAB receptor-mediated postsynaptic responses on cortical pyramidal cells and establish electrical synapses with various interneuron types. However, the involvement of GABAB receptors in postsynaptic effects of neurogliaform cells on other GABAergic interneurons is not clear. We measured the postsynaptic effects of neurogliaform cells in vitro applying simultaneous whole-cell recordings in human and rat cortex. Single action potentials...

  20. Connexin 43 controls the multipolar phase of neuronal migration to the cerebral cortex.

    Science.gov (United States)

    Liu, Xiuxin; Sun, Lin; Torii, Masaaki; Rakic, Pasko

    2012-05-22

    The prospective pyramidal neurons, migrating from the proliferative ventricular zone to the overlaying cortical plate, assume multipolar morphology while passing through the transient subventricular zone. Here, we show that this morphogenetic transformation, from the bipolar to the mutipolar and then back to bipolar again, is associated with expression of connexin 43 (Cx43) and, that knockdown of Cx43 retards, whereas its overexpression enhances, this morphogenetic process. In addition, we have observed that knockdown of Cx43 reduces expression of p27, whereas overexpression of p27 rescues the effect of Cx43 knockdown in the multipolar neurons. Furthermore, functional gap junction/hemichannel domain, and the C-terminal domain of Cx43, independently enhance the expression of p27 and promote the morphological transformation and migration of the multipolar neurons in the SVZ/IZ. Collectively, these results indicate that Cx43 regulates the passage of migrating neurons through their multipolar stage via p27 signaling and that interference with this process, by either genetic and/or environmental factors, may cause cortical malformations. PMID:22566616

  1. Stem/progenitor cells in the cerebral cortex of the human preterm: a resource for an endogenous regenerative neuronal medicine?

    Directory of Open Access Journals (Sweden)

    Laura Vinci

    2016-04-01

    Full Text Available The development of the central nervous system represents a very delicate period of embryogenesis. Premature interruption of neurogenesis in human preterm newborns can lead to motor deficits, including cerebral palsy, and significant cognitive, behavioral or sensory deficits in childhood. Preterm infants also have a higher risk of developing neurodegenerative diseases later in life. In the last decade, great importance has been given to stem/progenitor cells and their possible role in the development and treatment of several neurological disorders. Several studies, mainly carried out on experimental models, evidenced that immunohistochemistry may allow the identification of different neural and glial precursors inside the developing cerebral cortex. However, only a few studies have been performed on markers of human stem cells in the embryonic period.This review aims at illustrating the importance of stem/progenitor cells in cerebral cortex during pre- and post-natal life. Defining the immunohistochemical markers of stem/progenitor cells in the human cerebral cortex during development may be important to develop an “endogenous” target therapy in the perinatal period. Proceedings of the 2nd International Course on Perinatal Pathology (part of the 11th International Workshop on Neonatology · October 26th-31st, 2015 · Cagliari (Italy · October 31st, 2015 · Stem cells: present and future Guest Editors: Gavino Faa, Vassilios Fanos, Antonio Giordano

  2. Zbtb20-Induced CA1 Pyramidal Neuron Development and Area Enlargement in the Cerebral Midline Cortex of Mice

    DEFF Research Database (Denmark)

    Nielsen, Jakob V; Blom, Jonas B; Noraberg, Jens;

    2010-01-01

    Expression of the transcriptional repressor Zbtb20 is confined to the hippocampal primordium of the developing dorsal midline cortex in mice. Here, we show that misexpression of Zbtb20 converts projection neurons of the subiculum and postsubiculum (dorsal presubiculum) to CA1 pyramidal neurons...... that are innervated by Schaffer collateral projections in ectopic strata oriens and radiatum. The Zbtb20-transformed neurons express Bcl11B, Satb2, and Calbindin-D28k, which are markers of adult CA1 pyramidal neurons. Downregulation of Zbtb20 expression by RNA interference impairs the normal maturation of CA1...... pyramidal neurons resulting in deficiencies in Calbindin-D28k expression and in reduced apical dendritic arborizations in stratum lacunosum moleculare. Overall, the results show that Zbtb20 is required for various aspects of CA1 pyramidal neuron development such as the postnatal extension of apical...

  3. Wnt signaling regulates multipolar-to-bipolar transition of migrating neurons in the cerebral cortex.

    Science.gov (United States)

    Boitard, Michael; Bocchi, Riccardo; Egervari, Kristof; Petrenko, Volodymyr; Viale, Beatrice; Gremaud, Stéphane; Zgraggen, Eloisa; Salmon, Patrick; Kiss, Jozsef Z

    2015-03-01

    The precise timing of pyramidal cell migration from the ventricular germinal zone to the cortical plate is essential for establishing cortical layers, and migration errors can lead to neurodevelopmental disorders underlying psychiatric and neurological diseases. Here, we report that Wnt canonical as well as non-canonical signaling is active in pyramidal precursors during radial migration. We demonstrate using constitutive and conditional genetic strategies that transient downregulation of canonical Wnt/β-catenin signaling during the multipolar stage plays a critical role in polarizing and orienting cells for radial migration. In addition, we show that reduced canonical Wnt signaling is triggered cell autonomously by time-dependent expression of Wnt5A and activation of non-canonical signaling. We identify ephrin-B1 as a canonical Wnt-signaling-regulated target in control of the multipolar-to-bipolar switch. These findings highlight the critical role of Wnt signaling activity in neuronal positioning during cortical development. PMID:25732825

  4. Cognitive phase transitions in the cerebral cortex enhancing the neuron doctrine by modeling neural fields

    CERN Document Server

    Kozma, Robert

    2016-01-01

    This intriguing book was born out of the many discussions the authors had in the past 10 years about the role of scale-free structure and dynamics in producing intelligent behavior in brains. The microscopic dynamics of neural networks is well described by the prevailing paradigm based in a narrow interpretation of the neuron doctrine. This book broadens the doctrine by incorporating the dynamics of neural fields, as first revealed by modeling with differential equations (K-sets).  The book broadens that approach by application of random graph theory (neuropercolation). The book concludes with diverse commentaries that exemplify the wide range of mathematical/conceptual approaches to neural fields. This book is intended for researchers, postdocs, and graduate students, who see the limitations of network theory and seek a beachhead from which to embark on mesoscopic and macroscopic neurodynamics.

  5. Wnt Signaling Regulates Multipolar-to-Bipolar Transition of Migrating Neurons in the Cerebral Cortex

    Directory of Open Access Journals (Sweden)

    Michael Boitard

    2015-03-01

    Full Text Available The precise timing of pyramidal cell migration from the ventricular germinal zone to the cortical plate is essential for establishing cortical layers, and migration errors can lead to neurodevelopmental disorders underlying psychiatric and neurological diseases. Here, we report that Wnt canonical as well as non-canonical signaling is active in pyramidal precursors during radial migration. We demonstrate using constitutive and conditional genetic strategies that transient downregulation of canonical Wnt/β-catenin signaling during the multipolar stage plays a critical role in polarizing and orienting cells for radial migration. In addition, we show that reduced canonical Wnt signaling is triggered cell autonomously by time-dependent expression of Wnt5A and activation of non-canonical signaling. We identify ephrin-B1 as a canonical Wnt-signaling-regulated target in control of the multipolar-to-bipolar switch. These findings highlight the critical role of Wnt signaling activity in neuronal positioning during cortical development.

  6. The human cerebral cortex is neither one nor many: Neuronal distribution reveals two quantitatively different zones in the grey matter, three in the white matter, and explains local variations in cortical folding

    Directory of Open Access Journals (Sweden)

    Pedro F. M. Ribeiro

    2013-09-01

    Full Text Available The human prefrontal cortex has been considered different in several aspects and relatively enlarged compared to the rest of the cortical areas. Here we determine whether the white and gray matter of the prefrontal portion of the human cerebral cortex have similar or different cellular compositions relative to the rest of the cortical regions by applying the Isotropic Fractionator to analyze the distribution of neurons along the entire anteroposterior axis of the cortex, and its relationship with the degree of gyrification, number of neurons under the cortical surface, and other parameters. The prefrontal region shares with the remainder of the cerebral cortex (except for occipital cortex the same relationship between cortical volume and number of neurons. In contrast, both occipital and prefrontal areas vary from other cortical areas in their connectivity through the white matter, with a systematic reduction of cortical connectivity through the white matter and an increase of the mean axon caliber along the anteroposterior axis. These two parameters explain local differences in the distribution of neurons underneath the cortical surface. We also show that local variations in cortical folding are neither a function of local numbers of neurons nor of cortical thickness, but correlate with properties of the white matter, and are best explained by the folding of the white matter surface. Our results suggest that the human cerebral cortex is divided in two zones (occipital and non-occipital that differ in how neurons distributed across their grey matter volume and in three zones (prefrontal, occipital, and non-occipital that differ in how neurons are connected through the white matter. Thus, the human prefrontal cortex has the largest fraction of neuronal connectivity through the white matter and the smallest average axonal caliber in the white matter within the cortex, although its neuronal composition fits the pattern found for other, non

  7. Cerebral cortex modulation of pain

    Institute of Scientific and Technical Information of China (English)

    Yu-feng XIE; Fu-quan HUO; Jing-shi TANG

    2009-01-01

    Pain is a complex experience encompassing sensory-discriminative, affective-motivational and cognitiv e-emotional com-ponents mediated by different mechanisms. Contrary to the traditional view that the cerebral cortex is not involved in pain perception, an extensive cortical network associated with pain processing has been revealed using multiple methods over the past decades. This network consistently includes, at least, the anterior cingulate cortex, the agranular insular cortex, the primary (SⅠ) and secondary somatosensory (SⅡ) cortices, the ventrolateral orbital cortex and the motor cortex. These corti-cal structures constitute the medial and lateral pain systems, the nucleus submedius-ventrolateral orbital cortex-periaque-ductal gray system and motor cortex system, respectively. Multiple neurotransmitters, including opioid, glutamate, GABA and dopamine, are involved in the modulation of pain by these cortical structures. In addition, glial cells may also be in-volved in cortical modulation of pain and serve as one target for pain management research. This review discusses recent studies of pain modulation by these cerebral cortical structures in animals and human.

  8. Experimental study on alteration of adrenergic receptors activity in neuronal membranes protein of cerebral cortex following brain trauma in rats

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xin-wei; XU Ru-xiang; QI Yi-long; CHEN Chang-cai

    2001-01-01

    Objective: To define the course of changes taken by α1 and β adrenergic receptors (AR) activity after traumatic brain injury (TBI) and explore the approach for secondary brain injury (SBI) management. Methods: The neuronal membrane protein of cortex were extracted from the rats subject to traumatic brain injury, and the changes of α1- and β-AR activities in the neuronal membranes were examined by radio ligand binding assay (RLBA). Results: α1- and β-AR activities underwent obvious changes, reaching their peak values at 24 h after TBI. α1-AR binding density (Bmax) reduced by 22.6%while the ligand affinity increased by 66.7%, and for β-AR, however, Bmax increased by 116.9% and the ligand affinity reduced by 50.7%. Their antagonists could counteract the changes ofα1- and β-AR activity. Conclusion: The patterns of changes varies between α1- and β-AR activity after TBI, suggesting their different roles in the neuronal membranes after brain trauma, and timely administration of AR antagonists is potentially beneficial in TBI management.

  9. The Role of Neonatal Carnitine Palmitoyl Transferase Deficiency Type II on Proliferation of Neuronal Progenitor Cells and Layering of the Cerebral Cortex in the Developing Brain

    Directory of Open Access Journals (Sweden)

    Heepeel Chang

    2007-06-01

    Full Text Available Neonatal Carnitine Palmitoyl Transferase Deficiency Type II, characterized by the absence of CPT II enzyme, is one of the lethal disorders of mitochondrial fatty acid oxidation. CPT II regulates the conversion of long chain fatty acids, so that its product, acyl-CoA esters, can enter the Krebs cycle and generate energy. Neonatal mutations of CPT II lead to severe disruption of the metabolism of long-chain fatty acids and result in dysmorphic features, cystic renal dysplasia, and neuronal migration defects. Examination of the brain from an approximately 15-week gestation human fetus with CPT II deficiency revealed premature formation of cerebral cortical gyri and sulci and significantly lower levels of neuronal cell proliferation in the ventricular and subventricular zones as compared to the reference cases. We used immunohistochemical markers to further characterize the effect of CPT II deficiency on progenitor cell proliferation and layering of neurons. These studies demonstrated a premature generation of layer 5 cortical neurons. In addition, both the total number and percentage of progenitor cells proliferating in the ventricular zone were markedly reduced in the CPT II case in comparison to a reference case. Our results indicate that CPT II deficiency alters the normal program of cellular proliferation and differentiation in the cortex, with early differentiation of progenitor cells associated with premature cortical maturation.

  10. Alterations in cortical thickness and neuronal density in the frontal cortex of Albert Einstein.

    Science.gov (United States)

    Anderson, B; Harvey, T

    1996-06-01

    Neuronal density, neuron size, and the number of neurons under 1 mm2 of cerebral cortical surface area were measured in the right pre-frontal cortex of Albert Einstein and five elderly control subjects. Measurement of neuronal density used the optical dissector technique on celloidin-embedded cresyl violet-stained sections. The neurons counted provided a systematic random sample for the measurement of cell body cross-sectional area. Einstein's cortex did not differ from the control subjects in the number of neurons under 1 mm2 of cerebral cortex or in mean neuronal size. Because Einstein's cortex was thinner than the controls he had a greater neuronal density.

  11. Early GABAergic circuitry in the cerebral cortex.

    Science.gov (United States)

    Luhmann, Heiko J; Kirischuk, Sergei; Sinning, Anne; Kilb, Werner

    2014-06-01

    In the cerebral cortex GABAergic signaling plays an important role in regulating early developmental processes, for example, neurogenesis, migration and differentiation. Transient cell populations, namely Cajal-Retzius in the marginal zone and thalamic input receiving subplate neurons, are integrated as active elements in transitory GABAergic circuits. Although immature pyramidal neurons receive GABAergic synaptic inputs already at fetal stages, they are integrated into functional GABAergic circuits only several days later. In consequence, GABAergic synaptic transmission has only a minor influence on spontaneous network activity during early corticogenesis. Concurrent with the gradual developmental shift of GABA action from excitatory to inhibitory and the maturation of cortical synaptic connections, GABA becomes more important in synchronizing neuronal network activity.

  12. Mutual regulation between Satb2 and Fezf2 promotes subcerebral projection neuron identity in the developing cerebral cortex.

    Science.gov (United States)

    McKenna, William L; Ortiz-Londono, Christian F; Mathew, Thomas K; Hoang, Kendy; Katzman, Sol; Chen, Bin

    2015-09-15

    Generation of distinct cortical projection neuron subtypes during development relies in part on repression of alternative neuron identities. It was reported that the special AT-rich sequence-binding protein 2 (Satb2) is required for proper development of callosal neuron identity and represses expression of genes that are essential for subcerebral axon development. Surprisingly, Satb2 has recently been shown to be necessary for subcerebral axon development. Here, we unravel a previously unidentified mechanism underlying this paradox. We show that SATB2 directly activates transcription of forebrain embryonic zinc finger 2 (Fezf2) and SRY-box 5 (Sox5), genes essential for subcerebral neuron development. We find that the mutual regulation between Satb2 and Fezf2 enables Satb2 to promote subcerebral neuron identity in layer 5 neurons, and to repress subcerebral characters in callosal neurons. Thus, Satb2 promotes the development of callosal and subcerebral neurons in a cell context-dependent manner.

  13. Spindle Bursts in Neonatal Rat Cerebral Cortex

    Directory of Open Access Journals (Sweden)

    Jenq-Wei Yang

    2016-01-01

    Full Text Available Spontaneous and sensory evoked spindle bursts represent a functional hallmark of the developing cerebral cortex in vitro and in vivo. They have been observed in various neocortical areas of numerous species, including newborn rodents and preterm human infants. Spindle bursts are generated in complex neocortical-subcortical circuits involving in many cases the participation of motor brain regions. Together with early gamma oscillations, spindle bursts synchronize the activity of a local neuronal network organized in a cortical column. Disturbances in spindle burst activity during corticogenesis may contribute to disorders in cortical architecture and in the activity-dependent control of programmed cell death. In this review we discuss (i the functional properties of spindle bursts, (ii the mechanisms underlying their generation, (iii the synchronous patterns and cortical networks associated with spindle bursts, and (iv the physiological and pathophysiological role of spindle bursts during early cortical development.

  14. Spindle Bursts in Neonatal Rat Cerebral Cortex.

    Science.gov (United States)

    Yang, Jenq-Wei; Reyes-Puerta, Vicente; Kilb, Werner; Luhmann, Heiko J

    2016-01-01

    Spontaneous and sensory evoked spindle bursts represent a functional hallmark of the developing cerebral cortex in vitro and in vivo. They have been observed in various neocortical areas of numerous species, including newborn rodents and preterm human infants. Spindle bursts are generated in complex neocortical-subcortical circuits involving in many cases the participation of motor brain regions. Together with early gamma oscillations, spindle bursts synchronize the activity of a local neuronal network organized in a cortical column. Disturbances in spindle burst activity during corticogenesis may contribute to disorders in cortical architecture and in the activity-dependent control of programmed cell death. In this review we discuss (i) the functional properties of spindle bursts, (ii) the mechanisms underlying their generation, (iii) the synchronous patterns and cortical networks associated with spindle bursts, and (iv) the physiological and pathophysiological role of spindle bursts during early cortical development.

  15. [Macro- and microscopic systematization of cerebral cortex malformations in children].

    Science.gov (United States)

    Milovanov, A P; Milovanova, O A

    2011-01-01

    For the first time in pediatric pathologicoanatomic practice the complete systematization of cerebral cortex malformations is represented. Organ, macroscopic forms: microencephaly, macroencephaly, micropolygyria, pachygyria, schizencephaly, porencephaly, lissencephaly. Histic microdysgenesis of cortex: type I includes isolated abnormalities such as radial (IA) and tangential (I B) subtypes of cortical dislamination; type II includes sublocal cortical dislamination with immature dysmorphic neurons (II A) and balloon cells (II B); type III are the combination focal cortical dysplasia with tuberous sclerosis of the hippocampus (III A), tumors (III B) and malformations of vessels, traumatic and hypoxic disorders (III C). Band heterotopias. Subependimal nodular heterotopias. Tuberous sclerosis. Cellular typification of cortical dysplasia: immature neurons and balloon cells.

  16. [Changes in the intragastric contents during sleep affect the statistical characteristics of the neuronal activity in cerebral cortex].

    Science.gov (United States)

    Pigarev, I N; Bibikov, N G; Busygina, I I

    2014-06-01

    Firing activity in somatosensory cortical area was analyzed in cats during slow wave sleep. Statistical characteristics of the background activity were calculated before and after changes of the intragastric contents (introduction of 50 ml of water into stomach). This procedure did not affect the depth of sleep. There were no changes of the mean firing frequency and the local variation coefficients. To evaluate the degree of chaos in neuronal firing before and after changes of the intragastric contents, the dependence of the Fano factor from the length of the intervals of analysis was calculated. This dependence before water infusion for 40 neurons expressed as a power function with index of power > 0.2 what indicated on fractal nature of the background activity. The changes of the gastric contents in 18 neurons lead to considerable changes of the indexes of power of this function. It is known that in wakefulness for cortical neurons these indexes are dependent on the specific sensory stimulation. Thus, our results can be considered as an indication that during slow wave sleep signals from stomach are included in the afferent flow to the cortical areas, which in wakefulness are involved in somatosensory functions. PMID:25665397

  17. Emergence of Complex Wave Patterns in Primate Cerebral Cortex

    OpenAIRE

    Townsend, Rory G.; Solomon, Selina S.; Chen, Spencer C.; Pietersen, Alexander N.J.; Martin, Paul R.; Solomon, Samuel G.; Gong, Pulin

    2015-01-01

    Slow brain rhythms are attributed to near-simultaneous (synchronous) changes in activity in neuron populations in the brain. Because they are slow and widespread, synchronous rhythms have not been considered crucial for information processing in the waking state. Here we adapted methods from turbulence physics to analyze δ-band (1–4 Hz) rhythms in local field potential (LFP) activity, in multielectrode recordings from cerebral cortex in anesthetized marmoset monkeys. We found that synchrony c...

  18. Sleep-active cells in the cerebral cortex and their role in slow-wave activity

    OpenAIRE

    Gerashchenko, Dmitry; Wisor, Jonathan P.; Kilduff, Thomas S.

    2011-01-01

    We recently identified neurons in the cerebral cortex that become activated during sleep episodes with high slow-wave activity (SWA). The distinctive properties of these neurons are the ability to produce nitric oxide and their long-range projections within the cortex. In this review, we discuss how these characteristics of sleep-active cells could be relevant to SWA production in the cortex. We also discuss possible models of the role of nNOS cells in SWA production.

  19. Cellular scaling rules for the brain of Artiodactyla include a highly folded cortex with few neurons

    Directory of Open Access Journals (Sweden)

    Rodrigo eSiqueira Kazu

    2014-11-01

    Full Text Available Quantitative analysis of the cellular composition of rodent, primate, insectivore and afrotherian brains has shown that nonneuronal scaling rules are similar across these mammalian orders that diverged about 95 million years ago, and therefore appear to be conserved in evolution, while neuronal scaling rules appear to be free to vary in a clade-specific manner. Here we analyze the cellular scaling rules that apply to the brain of artiodactyls, a group within the order Cetartiodactyla, believed to be a relatively recent radiation from the common Eutherian ancestor. We find that artiodactyls share nonneuronal scaling rules with all groups analyzed previously. Artiodactyls share with afrotherians and rodents, but not with primates, the neuronal scaling rules that apply to the cerebral cortex and cerebellum. The neuronal scaling rules that apply to the remaining brain areas are however distinct in artiodactyls. Importantly, we show that the folding index of the cerebral cortex scales with the number of neurons in the cerebral cortex in distinct fashions across artiodactyls, afrotherians, rodents, and primates, such that the artiodactyl cerebral cortex is more convoluted than primate cortices of similar numbers of neurons. Our findings suggest that the scaling rules found to be shared across modern afrotherians, glires and artiodactyls applied to the common Eutherian ancestor, such as the relationship between the mass of the cerebral cortex as a whole and its number of neurons. In turn, the distribution of neurons along the surface of the cerebral cortex, which is related to its degree of gyrification, appears to be a clade-specific characteristic. If the neuronal scaling rules for artiodactyls extend to all cetartiodactyls, we predict that the large cerebral cortex of cetaceans will still have fewer neurons than the human cerebral cortex.

  20. Neuronal autophagy in cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Feng Xu; Jin-Hua Gu; Zheng-Hong Qin

    2012-01-01

    Autophagy has evolved as a conserved process for the bulk degradation and recycling of cytosolic components,such as long-lived proteins and organelles.In neurons,autophagy is important for homeostasis and protein quality control and is maintained at relatively low levels under normal conditions,while it is upregulated in response to pathophysiological conditions,such as cerebral ischemic injury.However,the role of autophagy is more complex.It depends on age or brain maturity,region,severity of insult,and the stage of ischemia.Whether autophagy plays a beneficial or a detrimental role in cerebral ischemia depends on various pathological conditions.In this review,we elucidate the role of neuronal autophagy in cerebral ischemia.

  1. High membrane protein oxidation in the human cerebral cortex

    Directory of Open Access Journals (Sweden)

    Matthias Granold

    2015-04-01

    Full Text Available Oxidative stress is thought to be one of the main mediators of neuronal damage in human neurodegenerative disease. Still, the dissection of causal relationships has turned out to be remarkably difficult. Here, we have analyzed global protein oxidation in terms of carbonylation of membrane proteins and cytoplasmic proteins in three different mammalian species: aged human cortex and cerebellum from patients with or without Alzheimer's disease, mouse cortex and cerebellum from young and old animals, and adult rat hippocampus and cortex subjected or not subjected to cerebral ischemia. Most tissues showed relatively similar levels of protein oxidation. However, human cortex was affected by severe membrane protein oxidation, while exhibiting lower than average cytoplasmic protein oxidation. In contrast, ex vivo autooxidation of murine cortical tissue primarily induced aqueous protein oxidation, while in vivo biological aging or cerebral ischemia had no major effect on brain protein oxidation. The unusually high levels of membrane protein oxidation in the human cortex were also not predicted by lipid peroxidation, as the levels of isoprostane immunoreactivity in human samples were considerably lower than in rodent tissues. Our results indicate that the aged human cortex is under steady pressure from specific and potentially detrimental membrane protein oxidation. The pronounced difference between humans, mice and rats regarding the primary site of cortical oxidation might have contributed to the unresolved difficulties in translating into therapies the wealth of data describing successful antioxidant neuroprotection in rodents.

  2. Regulation of cerebral cortex development by Rho GTPases: insights from in vivo studies

    Directory of Open Access Journals (Sweden)

    Roberta eAzzarelli

    2015-01-01

    Full Text Available The cerebral cortex is the site of higher human cognitive and motor functions. Histologically, it is organized into six horizontal layers, each containing unique populations of molecularly and functionally distinct excitatory projection neurons and inhibitory interneurons. The stereotyped cellular distribution of cortical neurons is crucial for the formation of functional neural circuits and it is predominantly established during embryonic development. Cortical neuron development is a multiphasic process characterized by sequential steps of neural progenitor proliferation, cell cycle exit, neuroblast migration and neuronal differentiation. This series of events requires an extensive and dynamic remodeling of the cell cytoskeleton at each step of the process. As major regulators of the cytoskeleton, the family of small Rho GTPases has been shown to play essential functions in cerebral cortex development. Here we review in vivo findings that support the contribution of Rho GTPases to cortical projection neuron development and we address their involvement in the etiology of cerebral cortex malformations.

  3. Corticofugal GABAergic projection neurons in the mouse frontal cortex

    Directory of Open Access Journals (Sweden)

    Ryohei eTomioka

    2015-10-01

    Full Text Available Cortical projection neurons are classified by hodology in corticocortical, commissural and corticofugal subtypes. Although cortical projection neurons had been regarded as only glutamatergic neurons, recently corticocortical GABAergic projection neurons has been also reported in several species. Here we demonstrate corticofugal GABAergic projection neurons in the mouse frontal cortex. We employed viral-vector-mediated anterograde tracing, classical retrograde tracing, and immunohistochemistry to characterize neocortical GABAergic projection neurons. Injections of the Cre-dependent adeno-associated virus into glutamate decarboxylase 67-Cre knock-in mice revealed neocortical GABAergic projections widely to the forebrain, including the cerebral cortices, caudate putamen, ventral pallidum, lateral globus pallidus, nucleus accumbens, and olfactory tubercle. Minor GABAergic projections were also found in the mediodorsal thalamic nucleus, diagonal band of Broca, medial globus pallidus, substantial nigra, and dorsal raphe nucleus. Retrograde tracing studies also demonstrated corticofugal GABAergic projection neurons in the mouse frontal cortex. Further immunohistochemical screening with neurochemical markers revealed the majority of corticostriatal GABAergic projection neurons were positive for somatostatin-immunoreactivity. In contrast, corticothalamic GABAergic projection neurons were not identified by representative neurochemical markers for GABAergic neurons. These findings suggest that corticofugal GABAergic projection neurons are heterogeneous in terms of their neurochemical properties and target nuclei, and provide axonal innervations mainly to the nuclei in the basal ganglia.

  4. Does Cell Lineage in the Developing Cerebral Cortex Contribute to its Columnar Organization?

    OpenAIRE

    Costa, Marcos R.; Cecilia Hedin-Pereira

    2010-01-01

    Since the pioneer work of Lorente de Nó, Ramón y Cajal, Brodmann, Mountcastle, Hubel and Wiesel and others, the cerebral cortex has been seen as a jigsaw of anatomic and functional modules involved in the processing of different sets of information. In fact, a columnar distribution of neurons displaying similar functional properties throughout the cerebral cortex has been observed by many researchers. Although it has been suggested that much of the anatomical substrate for such ...

  5. Prenatal cocaine exposure decreases parvalbumin-immunoreactive neurons and GABA-to-projection neuron ratio in the medial prefrontal cortex.

    Science.gov (United States)

    McCarthy, Deirdre M; Bhide, Pradeep G

    2012-01-01

    Cocaine abuse during pregnancy produces harmful effects not only on the mother but also on the unborn child. The neurotransmitters dopamine and serotonin are known as the principal targets of the action of cocaine in the fetal and postnatal brain. However, recent evidence suggests that cocaine can impair cerebral cortical GABA neuron development and function. We sought to analyze the effects of prenatal cocaine exposure on the number and distribution of GABA and projection neurons (inhibitory interneurons and excitatory output neurons, respectively) in the mouse cerebral cortex. We found that the prenatal cocaine exposure decreased GABA neuron numbers and GABA-to-projection neuron ratio in the medial prefrontal cortex of 60-day-old mice. The neighboring prefrontal cortex did not show significant changes in either of these measures. However, there was a significant increase in projection neuron numbers in the prefrontal cortex but not in the medial prefrontal cortex. Thus, the effects of cocaine on GABA and projection neurons appear to be cortical region specific. The population of parvalbumin-immunoreactive GABA neurons was decreased in the medial prefrontal cortex following the prenatal cocaine exposure. The cocaine exposure also delayed the developmental decline in the volume of the medial prefrontal cortex. Thus, prenatal cocaine exposure produced persisting and region-specific effects on cortical cytoarchitecture and impaired the physiological balance between excitatory and inhibitory neurotransmission. These structural changes may underlie the electrophysiological and behavioral effects of prenatal cocaine exposure observed in animal models and human subjects.

  6. Cerebral cortex: a target and source of insulin?

    Science.gov (United States)

    Csajbók, Éva A; Tamás, Gábor

    2016-08-01

    Recent results suggest that insulin is synthesised by a subpopulation of neurons in the cerebral cortex and neural progenitor cells of the hippocampus. Supplementing the slow supply of insulin to the brain by pancreatic beta cells, the insulin locally released by neurons provides a rapid means of regulating local microcircuits, effectively modulating synaptic transmission and on-demand energy homeostasis of neural networks. Modulation of insulin production by brain neurons via glucagon-like peptide 1 (GLP-1) agonists might be useful in counteracting diabetes, obesity and neurodegenerative diseases. Replacement of lost pancreatic beta cells by autologous transplantation of insulin-producing neural progenitor cells could be a viable therapy for diabetes. PMID:27207082

  7. Alpha-actinin expression at different differentiating time points from temporal lobe cerebral cortex neural stem cells to neuron-like cells using energy dispersive X-ray analysis

    Institute of Scientific and Technical Information of China (English)

    Bo YU; Hua Li; Zhe Du; Yang Hong; Meng Sang; Yuxiu Shi

    2009-01-01

    BACKGROUND: Alpha-actinin (a-actinin) plays a key role in neuronal growth cone migration during directional differentiation from neural stem cells (NSCs) to neurons.OBJECTIVE: To detect in situ microdistribution and quantitative expression of a-actinin during directional differentiation of NSCs to neurons in the temporal lobe cerebral cortex of neonatal rats.DESIGN, TIME AND SETTING: Between January 2006 and December 2008, culture and directional differentiation of NSCs were performed at Department of Histology and Embryology, Preclinical Medical College, China Medical University. Immune electron microscopy was performed at Department of Histology and Embryology and Department of Electron Micrology, Preclinical Medical College, China Medical University. Spectrum analysis was performed at Laboratory of Electron Microscopy, Mental Research Institute, Chinese Academy of Sciences.MATERIALS: Basic fibroblast growth factor, epidermal growth factor, brain-derived nerve growth factor, type-1 insulin like growth factor, and a-actinin antibody were provided by Gibco BRL, USA; rabbit-anti-rat nestin monoclonal antibody, rabbit-anti-rat neuron specific enolase polyclonal antibody, and EDAX-9100 energy dispersive X-ray analysis were provided by PHILIPS Company, Netherlands.METHODS: NSCs, following primary and passage culture, were differentiated with serum culture medium (DMEM/F12+10% fetal bovine serum+2 ng/mL brain-derived nerve growth factor+2 ng/mL type-1 insulin like growth factor).MAIN OUTCOME MEASURES: Expression of a-actinin in neuron-like cells was quantitatively and qualitatively detected with immunocytochemistry using energy dispersive X-ray analysis. RESULTS: Immunocytochemistry, combined with electron microscopy, indicated that positive a-actinin expression was like a spheroid particle with high electron density. In addition, the expression was gradually concentrated from the nuclear edge to the cytoplasm and expanded into developing neurites, during

  8. Cerebral cortical neurons with activity linked to central neurogenic spontaneous and evoked elevations in cerebral blood flow

    Science.gov (United States)

    Golanov, E. V.; Reis, D. J.

    1996-01-01

    We recorded neurons in rat cerebral cortex with activity relating to the neurogenic elevations in regional cerebral blood flow (rCBF) coupled to stereotyped bursts of EEG activity, burst-cerebrovascular wave complexes, appearing spontaneously or evoked by electrical stimulation of rostral ventrolateral medulla (RVL) or fastigial nucleus (FN). Of 333 spontaneously active neurons only 15 (5%), in layers 5-6, consistently (P neurons in deep cortical laminae whose activity correlates with neurogenic elevations of rCBF. These neurons may function to transduce afferent neuronal signals into vasodilation.

  9. Cultivation of Cerebral Cortex Neuronal Cells of Newborn BALB/c Mice%新生BALB/c小鼠大脑皮质神经元细胞培养方法的建立

    Institute of Scientific and Technical Information of China (English)

    辛岗; 苏芸; 王革非; 许燕璇; 李康生

    2011-01-01

    Objective: To establish a method for cultivation of cerebral cortex neuronal cells of newborn BALB/c mice. Methods: The cortexes from newborn(less than 24 h) BALB/c mice were obtained and digested by 0.25% trypsin, and then dissociated into single cell suspension. About 1×106 cells were seeded onto each 35 mm dish which was coated by poly-L-lysine overnight previously. After cultivated in seeding medium for 6 h, the neuron cells were cultured in neurobasal medium containing B27, FBS, and glutamine. Cytosine arabinofurannside was added to the cultures at a final concentration of 5 mg/mL on 40 h. Results: The neuron cells showed a typical morphorlogy at day 5. As indicated by indirect immunofluorescence using antibodies against neuron specific βⅢ tubulin, the purity of the neuronal cultures was 93%. Conlusion: The optimized method to culture neuron from BALB/c mice was established.%目的:经改良和优化,建立高纯度BALB/c小鼠大脑皮质神经元培养的方法.方法:采用L-多聚赖氨酸包被细胞培养板,取新生BALB/c小鼠(出生24 h内)大脑皮质组织,经0.25%胰酶消化后吹打成单个细胞,按1×106/孔接种于35 mm的六孔板中,用神经元细胞培养种植液培养6 h后换神经元细胞培养饲养液,培养40 h时加入阿糖胞苷抑制神经胶质细胞的生长,随时观察神经元培养情况.结果:培养5 d的神经元细胞形态最为典型;经免疫荧光方法鉴定,神经元细胞纯度为93%.结论:经方法改良与优化,获得了高纯度的原代培养小鼠大脑皮质神经元细胞.

  10. Ethanol induces heterotopias in organotypic cultures of rat cerebral cortex.

    Science.gov (United States)

    Mooney, Sandra M; Siegenthaler, Julie A; Miller, Michael W

    2004-10-01

    Abnormalities in the migration of cortical neurons to ectopic sites can be caused by prenatal exposure to ethanol. In extreme cases, cells migrate past the pial surface and form suprapial heterotopias or 'warts'. We used organotypic slice cultures from 17-day-old rat fetuses to examine structural and molecular changes that accompany wart formation. Cultures were exposed to ethanol (0, 200, 400 or 800 mg/dl) and maintained for 2-32 h. Fixed slices were sectioned and immunolabeled with antibodies directed against calretinin, reelin, nestin, GFAP, doublecortin, MAP-2 and NeuN. Ethanol promoted the widespread infiltration of the marginal zone (MZ) with neurons and the focal formation of warts. The appearance of warts is time- and concentration-dependent. Heterotopias comprised migrating neurons and were not detected in control slices. Warts were associated with breaches in the array of Cajal-Retzius cells and with translocation of reelin-immunoexpression from the MZ to the outer limit of the wart. Ethanol also altered the morphology of the radial glia. Thus, damage to the integrity of superficial cortex allows neurons to infiltrate the MZ, and if the pial-subpial glial barrier is also compromised these ectopic neurons can move beyond the normal cerebral limit to form a wart.

  11. Salient features of synaptic organisation in the cerebral cortex.

    Science.gov (United States)

    Somogyi, P; Tamás, G; Lujan, R; Buhl, E H

    1998-05-01

    The neuronal and synaptic organisation of the cerebral cortex appears exceedingly complex, and the definition of a basic cortical circuit in terms of defined classes of cells and connections is necessary to facilitate progress of its analysis. During the last two decades quantitative studies of the synaptic connectivity of identified cortical neurones and their molecular dissection revealed a number of general rules that apply to all areas of cortex. In this review, first the precise location of postsynaptic GABA and glutamate receptors is examined at cortical synapses, in order to define the site of synaptic interactions. It is argued that, due to the exclusion of G protein-coupled receptors from the postsynaptic density, the presence of extrasynaptic receptors and the molecular compartmentalisation of the postsynaptic membrane, the synapse should include membrane areas beyond the membrane specialisation. Subsequently, the following organisational principles are examined: 1. The cerebral cortex consists of: (i) a large population of principal neurones reciprocally connected to the thalamus and to each other via axon collaterals releasing excitatory amino acids, and, (ii) a smaller population of mainly local circuit GABAergic neurones. 2. Differential reciprocal connections are also formed amongst GABAergic neurones. 3. All extrinsic and intracortical glutamatergic pathways terminate on both the principal and the GABAergic neurones, differentially weighted according to the pathway. 4. Synapses of multiple sets of glutamatergic and GABAergic afferents subdivide the surface of cortical neurones and are often co-aligned on the dendritic domain. 5. A unique feature of the cortex is the GABAergic axo-axonic cell, influencing principal cells through GABAA receptors at synapses located exclusively on the axon initial segment. The analysis of these salient features of connectivity has revealed a remarkably selective array of connections, yet a highly adaptable design of

  12. Dynamic changes of apoptosis in rat cerebral cortex neurons after hypoxia%大鼠大脑皮层神经元缺氧后细胞凋亡情况的动态观察

    Institute of Scientific and Technical Information of China (English)

    邹哲华; 陶陶; 徐坚; 刘智; 罗开俭

    2012-01-01

    Objective To observe the dynamic changes of apoptosis in rat cerebral cortex neurons after hypoxia. Methods Rat cerebral cortex neurons were primarily cultured from SD rats born within 24 h and then identified by immunocytochemical assay. Then the identified cells were cultured in the medium containing 100 μmol/L CoCl2 to simulate hypoxic condition. The cells cultivated in normal condition served as normal control ( normoxia group). Ultrastructural changes of the neurons were observed by transmission electron microscopy (TEM) . Neuronal apoptosis were observed by TUNEL assay. Results TEM displayed that the morphology of neurons was normal, so was the structure of chromatin, endoplasmic reticulum and mitochondria in normoxia group, while, cellular edema, organelle damage or disappearance were seen in the hypoxia group. TUNEL showed that obvious apoptosis were found in hypoxic cells, with significant difference with normoxia group ( P < 0. 01). The apoptosis reached its peak in 48 h after hypoxia (0. 187 ±0. 007) , significantly higher than those in 12, 24 and 72 h (P <0. 01). Conclusion Apoptosis is a dynamic process in hypoxic-ischemic brain injury, and an important pattern of neuronal death. Intervention for neuronal apoptosis should be performed in an appropriate time window to effectively treat hypoxic-ischemic encephalopathy.%目的 观察大鼠大脑皮层神经元缺氧后细胞凋亡动态变化.方法 制备大鼠大脑皮层神经元体外原代培养模型,免疫细胞化学鉴定大鼠大脑皮层神经元,透射电镜下观察不同时间点各实验组神经元超微结构的变化,TUNEL法观察不同时间点各实验组神经元凋亡情况.结果 正常对照组神经元透射电镜下形态及染色质正常、内质网、线粒体等结构正常,缺氧组神经元水肿,细胞器破坏或消失;TUNEL法检测神经元凋亡:缺氧后各组神经元凋亡明显增加,与相应正常对照组相比有显著差异(P<0.01),缺氧48 h

  13. 脑缺血后大脑皮质神经生长因子和脑源性神经营养因子的改变%The Change of Nerve Growth Factor and Brain Derived Neurotrophic Factor in Neurons of Cerebral Cortex of Adult Rat Following Local Ischemia

    Institute of Scientific and Technical Information of China (English)

    曾兢; 王廷华; 张晓; 米兰兰; 高礼

    2001-01-01

    【内容摘要】目的探讨脑缺血后大脑皮质神经生长因子(NGF)、脑源性神经营养因子(BDNF)的变化。方法采用免疫组织化学ABC法观察NGF和BDNF的改变。结果 NGF、BDNF样免疫阳性反应物主要分布于大脑皮质第3、5层的神经元。脑缺血1小时后,NGF、BDNF在皮质神经元的表达明显增加。结论 NGF、BDNF与脑缺血后大脑皮质神经细胞的损伤修复有关。%Objective To acquire knowledge about the change of nerve growth factor (NGF) and brain derived neurotrophic factor (BDNF) in neurons of cerebral cortex of adult rat following local ischemia. Methods Using specific antiserums of NGF and BDNF by immunohistochemical ABC method. Results NGF-like and BDNF-like immunoreactions distributed mainly in the neurons of the third and fifth layers in cerebral cortex. After local ischemia, the average gray degrees of NGF and BDNF in neurons of cerebral cortex both decreased on the operated side more than on the un-operated side. Conclusion This experiment demonstrated that the levels of NGF and BDNF in neurons of cerebral cortex following ischemia were upregulated apparently, suggesting that NGF and BDNF may play an important role in the process of neurons' reaction after ischemia.

  14. Berberine Inhibits the Release of Glutamate in Nerve Terminals from Rat Cerebral Cortex

    OpenAIRE

    Tzu-Yu Lin; Yu-Wan Lin; Cheng-Wei Lu; Shu-Kuei Huang; Su-Jane Wang

    2013-01-01

    Berberine, an isoquinoline plant alkaloid, protects neurons against neurotoxicity. An excessive release of glutamate is considered to be one of the molecular mechanisms of neuronal damage in several neurological diseases. In this study, we investigated whether berberine could affect endogenous glutamate release in nerve terminals of rat cerebral cortex (synaptosomes) and explored the possible mechanism. Berberine inhibited the release of glutamate evoked by the K(+) channel blocker 4-aminopyr...

  15. Inhibitory effect of acupuncture on neuronal apoptosis in rats after cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Bangyu Ju; Jing Zhang; Guohua Jiang

    2007-01-01

    ; neuronal apoptosis was observed with TUNEL staining; manifestations of neuronal apoptosis in cerebral cortex and hippocampal CA1 area were observed with electron microscope.MAIN OUTCOME MEASURES: Neuronal injuries in hippocampal CA1 area after cerebral ischemia;neuronal apoptosis in cerebral cortex and hippocampal CA1 area after cerebral ischemia; morphological changes under electron microscope.RESULTS: Among 30 Wistar rats, 24 rats were involved in the final analysis. ① Expression of positive urons in cerebral cortex and hippocampal CA1 area with Nissl body staining: Neuronal defect was obvious in cerebral cortex and hippocampal CA1 area in the cerebral ischemia group as compared with that in the sham operation group (P < 0.05), and neuronal defect was decreased in hippocampal CA1 area in the cerebral ischemia group as compared with that in the acupuncture group (P < 0.05). ② Expression of positive neurons in cerebral cortex and hippocampal CA1 area with TUNEL staining: Positive neurons with TUNEL staining were not observed in the sham operation group, but positive neurons were increased in the cerebral ischemia group as compared with those in the acupuncture group (P <0.05). ③ Observational results of electron microscope: Neuronal apoptosis was not found in the sham operation group; neuronal apoptosis was rarely found in the acupuncture group; neuronal apoptosis was typical in the cerebral ischemia group.CONCLUSION: Delayed neuronal death after total cerebral ischemia may accompany ith apoptosis, but acupuncture may play a certain role in protecting nerve through inhibiting ischemic neuronal apoptosis.

  16. [Investigation of the Cerebral Cortex Using Magnetoencephalography(MEG)].

    Science.gov (United States)

    Kakigi, Ryusuke

    2015-04-01

    Cortical neurons are excited by signals from the thalamus that are conducted via thalamocortical fibers. As the cortex receives these signals, electric currents are conducted through the apical dendrites of pyramidal cells in the cerebral cortex. These electric currents generate magnetic fields. These electric and magnetic currents can be recorded by electroencephalography (EEG) and magnetoencephalography (MEG), respectively. The spatial resolution of MEG is higher than that of EEG because magnetic fields, unlike electric fields, are not affected by current conductivity. MEG also has several advantages over functional magnetic resonance imaging (fMRI). It (1) is completely non-invasive; (2) measures neuronal activity rather than blood flow or metabolic changes; (3) has a higher temporal resolution than fMRI on the order of milliseconds; (4) enables the measurement of stimulus-evoked and event-related responses; (5) enables the analysis of frequency (i.e., brain rhythm) response, which means that physiological changes can be analyzed spatiotemporally; and (6) enables the detailed analysis of results from an individual subject, which eliminates the need to average results over several subjects. This latter advantage of MEG therefore enables the analysis of inter-individual differences.

  17. 额叶皮层神经干细胞定向诱导分化类神经元的超微结构观察%Study on the ultrastructure of directional differentiation neuron-like cells of temporal lobe cerebral cortex neuron stem cell (NSC)

    Institute of Scientific and Technical Information of China (English)

    喻博; 刘云会; 刘冬娟; 石玉秀; 刘跃华; 杨蓓; 杜喆

    2008-01-01

    目的 研究大鼠额叶皮层神经干细胞(NSC)定向诱导分化类神经元细胞过程中的超微结构变化.方法 取Wistar出生24h新生鼠额叶脑组织加入神经生长因子进行干细胞的原代及继代培养SABC Nestin鉴定并定向培养,于1、3、7d进行扫描电镜观察.结果 神经干细胞诱导分化第7天的类神经元细胞扫描电镜观察可见胞体饱满,有树枝状分支,末端见鸭蹼状膨大的生长;透射电镜下观察可见细胞胞质中有大量的粗面内质网、线粒体与高尔基复体,脂滴糖原颗粒及微丝、微管,核膜、核仁清楚.结论 大脑额叶皮层神经干细胞经定向诱导分化形态学上能够分化成类神经元细胞结构.%Objective To evaluate the ultrastructure on frontal lobe cerebral cortex neuron stem cell ( NSC)in the process of directional differentiation neuron-like cells.Method Newborn Wistar animal in 24 hour was used,and the frontal lobe cerebral cortex tissue was scraped,primary generation and secondary culture with nerve nutrition factor were conducted.Immunochemistry SABC method was used to identify Nestin.Scan electron microscope(SEM)sample was prepared and observed on cover glass which taken from the raise board contain directional differentiation neuron at 1,3,7 day.Results Nearly mature,full soma,dendritic branches,duck palm shape apical cone on the terminal were obviously observed on SEM at 7 days.Some synapse type structure appeared on the cell surface.Organelles,massive RER,Golgi apparatus and the fat drop glycogen pellet was rich on TEM at 7 days.Microfilament and microtubule were in line,big and round nucleolus were clear.All these neuron-like cells characteristic were obvious and easy to see.Conclusions This study indicates that the frontal lobe cerebral cortex nerve stem cell can be directional induced differentiate to neuron-like cells.

  18. Cholinergic Mechanisms in the Cerebral Cortex: Beyond Synaptic Transmission.

    Science.gov (United States)

    Ovsepian, Saak V; O'Leary, Valerie B; Zaborszky, Laszlo

    2016-06-01

    Functional overviews of cholinergic mechanisms in the cerebral cortex have traditionally focused on the release of acetylcholine with modulator and transmitter effects. Recently, however, data have emerged that extend the role of acetylcholine and cholinergic innervations to a range of housekeeping and metabolic functions. These include regulation of amyloid precursor protein (APP) processing with production of amyloid β (Aβ) and other APP fragments and control of the phosphorylation of microtubule-associated protein (MAP) tau. Evidence has been also presented for receptor-ligand like interactions of cholinergic receptors with soluble Aβ peptide and MAP tau, with modulator and signaling effects. Moreover, high-affinity binding of Aβ to the neurotrophin receptor p75 (p75NTR) enriched in basalo-cortical cholinergic projections has been implicated in clearance of Aβ and nucleation of amyloid plaques. Here, we critically evaluate these unorthodox cholinergic mechanisms and discuss their role in neuronal physiology and the biology of Alzheimer's disease. PMID:26002948

  19. Mouse embryos and chimera cloned from neural cells in the postnatal cerebral cortex.

    Science.gov (United States)

    Makino, Hatsune; Yamazaki, Yukiko; Hirabayashi, Takahiro; Kaneko, Ryosuke; Hamada, Shun; Kawamura, Yoshimi; Osada, Tomoharu; Yanagimachi, Ryuzo; Yagi, Takeshi

    2005-01-01

    Cloning of mice has been achieved by transferring nuclei of various types of somatic cell nuclei into enucleated oocytes. However, all attempts to produce live cloned offspring using the nuclei of neurons from adult cerebral cortex have failed. Previously we obtained cloned mice using the nuclei of neural cells collected from fetal cerebral cortex. Here, we attempted to generate cloned mice using differentiated neurons from the cerebral cortex of postnatal (day 0-4) mice. Although we were unable to obtain live cloned pups, many fetuses reached day 10.5 days of development. These fetuses showed various abnormalities such as spherical omission of the neuroepithelium, collapsed lumen of neural tube, and aberrant expressions of marker proteins of neurons. We produced chimeric mice in which some hair cells and kidney cells were originated from differentiated neurons. In chimeric fetuses, LacZ-positive donor cells were in all three germ cell layers. However, chimeras with large contribution of donor-derived cells were not obtained. These results indicate that nuclei of differentiated neurons have lost their developmental totipotency. In other words, the conventional nuclear transfer technique does not allow nuclei of differentiated neurons to undergo complete genomic reprogramming required for normal embryonic development.

  20. Impaired cerebral cortex development and blood pressure regulation in FGF-2-deficient mice.

    Science.gov (United States)

    Dono, R; Texido, G; Dussel, R; Ehmke, H; Zeller, R

    1998-08-01

    Fibroblast growth factor-2 (FGF-2) has been implicated in various signaling processes which control embryonic growth and differentiation, adult physiology and pathology. To analyze the in vivo functions of this signaling molecule, the FGF-2 gene was inactivated by homologous recombination in mouse embryonic stem cells. FGF-2-deficient mice are viable, but display cerebral cortex defects at birth. Bromodeoxyuridine pulse labeling of embryos showed that proliferation of neuronal progenitors is normal, whereas a fraction of them fail to colonize their target layers in the cerebral cortex. A corresponding reduction in parvalbumin-positive neurons is observed in adult cortical layers. Neuronal defects are not limited to the cerebral cortex, as ectopic parvalbumin-positive neurons are present in the hippocampal commissure and neuronal deficiencies are observed in the cervical spinal cord. Physiological studies showed that FGF-2-deficient adult mice are hypotensive. They respond normally to angiotensin II-induced hypertension, whereas neural regulation of blood pressure by the baroreceptor reflex is impaired. The present genetic study establishes that FGF-2 participates in controlling fates, migration and differentiation of neuronal cells, whereas it is not essential for their proliferation. The observed autonomic dysfunction in FGF-2-deficient adult mice uncovers more general roles in neural development and function. PMID:9687490

  1. Fezf2 expression in layer 5 projection neurons of mature mouse motor cortex.

    Science.gov (United States)

    Tantirigama, Malinda L S; Oswald, Manfred J; Clare, Alison J; Wicky, Hollie E; Day, Robert C; Hughes, Stephanie M; Empson, Ruth M

    2016-03-01

    The mature cerebral cortex contains a wide diversity of neuron phenotypes. This diversity is specified during development by neuron-specific expression of key transcription factors, some of which are retained for the life of the animal. One of these key developmental transcription factors that is also retained in the adult is Fezf2, but the neuron types expressing it in the mature cortex are unknown. With a validated Fezf2-Gfp reporter mouse, whole-cell electrophysiology with morphology reconstruction, cluster analysis, in vivo retrograde labeling, and immunohistochemistry, we identify a heterogeneous population of Fezf2(+) neurons in both layer 5A and layer 5B of the mature motor cortex. Functional electrophysiology identified two distinct subtypes of Fezf2(+) neurons that resembled pyramidal tract projection neurons (PT-PNs) and intratelencephalic projection neurons (IT-PNs). Retrograde labeling confirmed the former type to include corticospinal projection neurons (CSpPNs) and corticothalamic projection neurons (CThPNs), whereas the latter type included crossed corticostriatal projection neurons (cCStrPNs) and crossed-corticocortical projection neurons (cCCPNs). The two Fezf2(+) subtypes expressed either CTIP2 or SATB2 to distinguish their physiological identity and confirmed that specific expression combinations of key transcription factors persist in the mature motor cortex. Our findings indicate a wider role for Fezf2 within gene expression networks that underpin the diversity of layer 5 cortical projection neurons.

  2. 3-N-butylphthalide improves neuronal morphology after chronic cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Wanhong Zhao; Chao Luo; Jue Wang; Jian Gong; Bin Li; Yingxia Gong; Jun Wang; Hanqin Wang

    2014-01-01

    3-N-butylphthalide is an effective drug for acute ischemic stroke. However, its effects on chronic cerebral ischemia-induced neuronal injury remain poorly understood. Therefore, this study li-gated bilateral carotid arteries in 15-month-old rats to simulate chronic cerebral ischemia in aged humans. Aged rats were then intragastrically administered 3-n-butylphthalide. 3-N-butylphtha-lide administration improved the neuronal morphology in the cerebral cortex and hippocampus of rats with chronic cerebral ischemia, increased choline acetyltransferase activity, and decreased malondialdehyde and amyloid beta levels, and greatly improved cognitive function. These findings suggest that 3-n-butylphthalide alleviates oxidative stress caused by chronic cerebral ischemia, improves cholinergic function, and inhibits amyloid beta accumulation, thereby im-proving cerebral neuronal injury and cognitive deifcits.

  3. Increased density of neurons containing NADPH diaphorase and nitric oxide synthase in the cerebral cortex of patients with HIV-1 infection and drug abuse.

    Science.gov (United States)

    Kuljis, Rodrigo O; Shapshak, Paul; Alcabes, Philip; Rodríguez de la Vega, Pura; Fujimura, Robert; Petito, Carol K

    2002-01-01

    To determine whether nitrogen monoxide (nitric oxide; NO) synthase (NOS) and NADPH diaphorase (NDP) co-containing cerebrocortical neurons (NOSN) neurons are affected in patients infected with human immunodeficiency virus type 1 (HIV-1) with and without associated intake of drugs of abuse, we examined the temporal neocortex of 24 individuals: 12 HIV-1 positive (including 3 drug users, 9 non-drug users) and 12 HIV-1 negative (including 6 drug users, and 6 non-drug users). Histochemical labeling for NDP-an enzymatic domain co-expressed in the NOS enzyme-was employed to visualize NOSN. Drug abuse and HIV-1 infection cause independently an increase in NOSN density, but combined they result in up to a 38-fold increase in NOSN density, suggesting that the combination of these factors induces NOS expression powerfully in neurons that normally do not synthesize NDP/NOS. This is associated with an increase in the proportion of NOSN displaying dystrophic changes, indicating that NOSN undergo massive degeneration in association with NOS synthesis induction. The increase in density of NOSN in HIV-1 infected drug abusers may be among the important sources of NO mediating cerebrocortical dysfunction, and the degeneration of NOS-containing local circuit neurons in patients with HIV-1 infection or drug abuse may underlie in part their neuropsychiatric manifestations. PMID:16873197

  4. Cerebellar vermis is a target of projections from the motor areas in the cerebral cortex.

    Science.gov (United States)

    Coffman, Keith A; Dum, Richard P; Strick, Peter L

    2011-09-20

    The cerebellum has a medial, cortico-nuclear zone consisting of the cerebellar vermis and the fastigial nucleus. Functionally, this zone is concerned with whole-body posture and locomotion. The vermis classically is thought to be included within the "spinocerebellum" and to receive somatic sensory input from ascending spinal pathways. In contrast, the lateral zone of the cerebellum is included in the "cerebro-cerebellum" because it is densely interconnected with the cerebral cortex. Here we report the surprising result that a portion of the vermis receives dense input from the cerebral cortex. We injected rabies virus into lobules VB-VIIIB of the vermis and used retrograde transneuronal transport of the virus to define disynaptic inputs to it. We found that large numbers of neurons in the primary motor cortex and in several motor areas on the medial wall of the hemisphere project to the vermis. Thus, our results challenge the classical view of the vermis and indicate that it no longer should be considered as entirely isolated from the cerebral cortex. Instead, lobules VB-VIIIB represent a site where the cortical motor areas can influence descending control systems involved in the regulation of whole-body posture and locomotion. We argue that the projection from the cerebral cortex to the vermis is part of the neural substrate for anticipatory postural adjustments and speculate that dysfunction of this system may underlie some forms of dystonia. PMID:21911381

  5. Roles of taurine-mediated tonic GABAA receptor activation in the radial migration of neurons in the fetal mouse cerebral cortex

    Directory of Open Access Journals (Sweden)

    Tomonori eFurukawa

    2014-03-01

    Full Text Available γ-Aminobutyric acid (GABA depolarizes embryonic cerebrocortical neurons and continuous activation of the GABAA receptor (GABAAR contributes to their tonic depolarization. Although multiple reports have demonstrated a role of GABAAR activation in neocortical development, including in migration, most of these studies have used pharmacological blockers. Herein, we performed in utero electroporation in GABA synthesis-lacking homozygous GAD67-GFP knock-in mice (GAD67GFP/GFP to label neurons born in the ventricular zone. Three days after electroporation, there were no differences in the distribution of labeled cells between the genotypes. The dose-response properties of cells labeled to detect GABA were equivalent among genotypes. However, continuous blockade of GABAAR with the GABAAR antagonist SR95531 accelerated radial migration. This effect of GABAAR blockade in GAD67GFP/GFP mice suggested a role for alternative endogenous GABAAR agonists. Thus, we tested the role of taurine, which is derived from maternal blood but is abundant in the fetal brain. The taurine-evoked currents in labeled cells were mediated by GABAAR. Taurine uptake was blocked by a taurine transporter inhibitor, 2-(guanidinoethanesulfonic acid (GES, and taurine release was blocked by a volume-sensitive anion channel blocker, 4-(2-butyl-6,7-dichlor-2-cyclopentylindan-1-on-5-yl oxobutyric acid (DCPIB, as examined through high-performance liquid chromatography (HPLC. GES increased the extracellular taurine concentration and induced an inward shift of the holding current, which was reversed by SR95531. In a taurine-deficient mouse model, the GABAAR-mediated tonic currents were greatly reduced, and radial migration was accelerated. As the tonic currents were equivalent among the genotypes of GAD67-GFP knock-in mice, taurine, rather than GABA, might play a major role as an endogenous agonist of embryonic tonic GABAAR conductance, regulating the radial migration of neurons in the

  6. Amygdala kindling potentiates seizure-stimulated immediate-early gene expression in rat cerebral cortex.

    Science.gov (United States)

    Duman, R S; Craig, J S; Winston, S M; Deutch, A Y; Hernandez, T D

    1992-11-01

    Kindling induces long-term adaptations in neuronal function that lead to a decreased threshold for induction of seizures. In the present study, the influence of amygdala kindling on levels of mRNA for the immediate-early genes (IEGs) c-fos, c-jun, and NGF1-A were examined both before and after an acute electroconvulsive seizure (ECS). Although amygdala kindling did not significantly influence resting levels of c-fos mRNA in cerebral cortex, ECS-stimulated levels of c-fos mRNA (examined 45 min after ECS) were approximately twofold greater in the cerebral cortex of kindled rats relative to sham-treated controls. The influence of kindling on IEG expression was dependent on the time course of kindling, as ECS-stimulated levels of c-fos mRNA were not significantly increased in stage 2 kindled animals. ECS-stimulated levels of c-jun and NGF1-A mRNA were also significantly increased in cerebral cortex of kindled rats relative to sham-treated controls. The influence of kindling on IEG expression was long-lasting because an acute ECS stimulus significantly elevated levels of c-fos and c-jun mRNA in the cerebral cortex of animals that were kindled 5 months previously. In contrast to these effects in cerebral cortex, kindling did not influence ECS-stimulated levels of c-fos mRNA in hippocampus. Finally, immunohistochemical studies revealed lamina-specific changes in the cerebral cortex.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Neuronal messengers in the human cerebral circulation

    DEFF Research Database (Denmark)

    Gulbenkian, S; Uddman, R; Edvinsson, L

    2001-01-01

    neuronal regulation of cerebral blood flow. Although little is known about the physiological actions and inter-relationships among all these putative neurotransmitters, their presence within cerebrovascular nerve fibers will make it necessary to revise our view on the mechanisms of cerebrovascular...

  8. Stimulus selectivity and response latency in putative inhibitory and excitatory neurons of the primate inferior temporal cortex

    OpenAIRE

    Mruczek, Ryan E. B.; David L Sheinberg

    2012-01-01

    The cerebral cortex is composed of many distinct classes of neurons. Numerous studies have demonstrated corresponding differences in neuronal properties across cell types, but these comparisons have largely been limited to conditions outside of awake, behaving animals. Thus the functional role of the various cell types is not well understood. Here, we investigate differences in the functional properties of two widespread and broad classes of cells in inferior temporal cortex of macaque monkey...

  9. Effect of propofol pretreatment on apoptosis in rat brain cortex after focal cerebral ischemia and reperfusion

    Institute of Scientific and Technical Information of China (English)

    Haiyan Xu; Chengwei Zhang; Chunxiao Zhang

    2011-01-01

    The present study aimed to observe cortical expression of Bcl-2 and Bax, cysteine-dependent aspartate directed proteases-3 activity and apoptotic cell death in a rat model of middle cerebral artery occlusion pretreated with propofol. Results showed that, propofol pretreatment significantly reduced oxidative stress levels and attenuated neuronal apoptosis in the cortex of rats. Propofol pretreatment upregulated Bcl-2 expression, and downregulated Bax expression and cysteine-dependent aspartate directed proteases-3 activity. These findings indicate that propofol pretreatment inhibits cell apoptosis during focal cerebral ischemia/reperfusion injury. This neuroprotective effect is most likely achieved through the Bcl-2/Bax/cysteine-dependent aspartate directed proteases-3 pathway.

  10. Immuno-localisation of anti-thyroid antibodies in adult human cerebral cortex.

    Science.gov (United States)

    Moodley, Kogie; Botha, Julia; Raidoo, Deshandra Munsamy; Naidoo, Strinivasen

    2011-03-15

    Expression of thyroid-stimulating hormone receptor (TSH-R) has been demonstrated in adipocytes, lymphocytes, bone, kidney, heart, intestine and rat brain. Immuno-reactive TSH-R has been localised in rat brain and human embryonic cerebral cortex but not in adult human brain. We designed a pilot study to determine whether anti-thyroid auto-antibodies immuno-localise in normal adult human cerebral cortex. Forensic samples from the frontal, motor, sensory, occipital, cingulate and parieto-occipito-temporal association cortices were obtained from five individuals who had died of trauma. Although there were no head injuries, the prior psychiatric history of patients was unknown. The tissues were probed with commercial antibodies against both human TSH-R and human thyroglobulin (TG). Anti-TSH-R IgG immuno-localised to cell bodies and axons of large neurones in all 6 regions of all 5 brains. The intensity and percentage of neurones labelled were similar in all tissue sections. TSH-R immuno-label was also observed in vascular endothelial cells in the cingulate gyrus. Although also found in all 5 brains and all six cortical regions, TG localised exclusively in vascular smooth muscle cells and not on neurones. Although limited by the small sample size and number of brain areas examined, this is the first study describing the presence of antigenic targets for anti-TSH-R IgG on human cortical neurons, and anti-TG IgG in cerebral vasculature. PMID:21196016

  11. Alteration of rat fetal cerebral cortex development after prenatal exposure to polychlorinated biphenyls.

    Directory of Open Access Journals (Sweden)

    Elise Naveau

    Full Text Available Polychlorinated biphenyls (PCBs are environmental contaminants that persist in environment and human tissues. Perinatal exposure to these endocrine disruptors causes cognitive deficits and learning disabilities in children. These effects may involve their ability to interfere with thyroid hormone (TH action. We tested the hypothesis that developmental exposure to PCBs can concomitantly alter TH levels and TH-regulated events during cerebral cortex development: progenitor proliferation, cell cycle exit and neuron migration. Pregnant rats exposed to the commercial PCB mixture Aroclor 1254 ended gestation with reduced total and free serum thyroxine levels. Exposure to Aroclor 1254 increased cell cycle exit of the neuronal progenitors and delayed radial neuronal migration in the fetal cortex. Progenitor cell proliferation, cell death and differentiation rate were not altered by prenatal exposure to PCBs. Given that PCBs remain ubiquitous, though diminishing, contaminants in human systems, it is important that we further understand their deleterious effects in the brain.

  12. Reduced Numbers of Somatostatin Receptors in the Cerebral Cortex in Alzheimer's Disease

    Science.gov (United States)

    Flint Beal, M.; Mazurek, Michael F.; Tran, Vinh T.; Chattha, Geetinder; Bird, Edward D.; Martin, Joseph B.

    1985-07-01

    Somatostatin receptor concentrations were measured in patients with Alzheimer's disease and controls. In the frontal cortex (Brodmann areas 6, 9, and 10) and temporal cortex (Brodmann area 21), the concentrations of somatostatin in receptors in the patients were reduced to approximately 50 percent of control values. A 40 percent reduction was seen in the hippocampus, while no significant changes were found in the cingulate cortex, postcentral gyrus, temporal pole, and superior temporal gyrus. Scatchard analysis showed a reduction in receptor number rather than a change in affinity. Somatostatin-like immunoreactivity was significantly reduced in both the frontal and temporal cortex. Somatostatin-like immunoreactivity was linearly related to somatostatin-receptor binding in the cortices of Alzheimer's patients. These findings may reflect degeneration of postsynaptic neurons or cortical afferents in the patients' cerebral cortices. Alternatively, decreased somatostatinlike immunoreactivity in Alzheimer's disease might indicate increased release of somatostatin and down regulation of postsynaptic receptors.

  13. Effect of Batroxobin on Neuronal Apoptosis During Focal Cerebral Ischemia and Reperfusion in Rats

    Institute of Scientific and Technical Information of China (English)

    吴卫平; 匡培根; 李振洲

    2001-01-01

    We have found that Batroxobin plays a protactive role in ischemic brain injury, which attracted us to investigate the effect of Batroxobin on apoptosis of neurons during cerebral ischemia and reperfusion. The apoptotic cells in ischemic rat brains at different reperfusion intervals were tested with method of TdT-mediated dUTP-DIG nick end labeling (TUNEL) and the effect of Batroxobin on the apoptosis of neurons was studied in left middle cerebral artery (LMCA) occlusion and reperfusion in rat models (n=18). The results showed that few scattered apoptosis cells were observed in right cerebral hemispheres after LMCA occlusion and reperfusion, and that a lot of apoptosis cells were found in left ischemic cortex and caudoputamen at 12h reperfusion, and they reached peak at 24h~48h reperfusion. However, in the rats pretreated with Batroxobin, the number of apoptosis cells in left cerebral cortex and caudoputamen reduced significantly and the neuronal damage was much milder at 24h reperfusion than that of saline-treated rats. The results indicate that administration of Batroxobin may reduce the apoptosis of neurons induced by cerebral ischemia and reperfusion and afford significant cerebroprotection in the model of focal cerebral ischemia and reperfusion.

  14. Emprego dos gangliosidos do cortex cerebral nas neuropatias perifericas

    Directory of Open Access Journals (Sweden)

    James Pitagoras De Mattos

    1981-12-01

    Full Text Available Os autores registram a experiência pessoal com o emprego de gangliosídios do cortex cerebral nas neuropatias periféricas. O ensaio clínico e eletromiográfico revelou-se eficaz em 30 dos 40 casos tratados. Enfatizam os melhores resultados em casos de paralisias faciais periféricas.

  15. Effect of Electroacupuncture on Expression of p53 Protein in Cerebral Cortex of Rats with Global Cerebral Ischemia/Reperfusion Injury

    Institute of Scientific and Technical Information of China (English)

    卜渊; 耿德勤; 葛巍; 徐兴顺; 曾因明

    2004-01-01

    Objective: To observe the effect of electroacupuncture (EA) on expression of p53 protein in cerebral cortex of senile rats with global cerebral ischemia/reperfusion (IR) injury and to explore its mechanism. Methods: The cerebral IR injury rat model was established referring to Pulsinelli 4-vessel occlusion method. Thirty-six SD rats were randomly and evenly divided into the control group, the IR group and the IR plus EA (IR-EA) group. The animals in the control group were subjected to electrocauterization of vertebral arteries in bilateral flank orifice alone with the general carotid arteries unoccluded.To rats in the IR-EA group, immediately and 24h, 48h, 72h after cerebral IR, EA treatment on bilateral acupoint "Zusanli"(ST36) was applied once a day, lasting for 60 minutes. After the final treatment, all the rats were sacrificed and their brains were taken to examine p53 protein expression by the immunohistochemical method. Results: Cells with positive p53 immunoreactivity in the cerebral cortex of rats in the IR group was significantly higher than that in the control group ( P<0.05), while that in the IR-EA group was significantly lower than that in the IR group (P<0.05). Conclusion: EA could remarkably reduce expression of p53 protein in the cerebral cortex of senile rats with global cerebral IR injury, which might be one of the means for EA to inhibit neuronal apoptosis after cerebral IR injury.

  16. Microglia in the Cerebral Cortex in Autism

    Science.gov (United States)

    Tetreault, Nicole A.; Hakeem, Atiya Y.; Jiang, Sue; Williams, Brian A.; Allman, Elizabeth; Wold, Barbara J.; Allman, John M.

    2012-01-01

    We immunocytochemically identified microglia in fronto-insular (FI) and visual cortex (VC) in autopsy brains of well-phenotyped subjects with autism and matched controls, and stereologically quantified the microglial densities. Densities were determined blind to phenotype using an optical fractionator probe. In FI, individuals with autism had…

  17. Coding of Vocalizations by Single Neurons in Ventrolateral Prefrontal Cortex

    OpenAIRE

    Plakke, Bethany; Diltz, Mark D.; Romanski, Lizabeth M.

    2013-01-01

    Neuronal activity in single prefrontal neurons has been correlated with behavioral responses, rules, task variables and stimulus features. In the non-human primate, neurons recorded in ventrolateral prefrontal cortex (VLPFC) have been found to respond to species-specific vocalizations. Previous studies have found multisensory neurons which respond to simultaneously presented faces and vocalizations in this region. Behavioral data suggests that face and vocal information are inextricably linke...

  18. High membrane protein oxidation in the human cerebral cortex

    OpenAIRE

    Matthias Granold; Bernd Moosmann; Irina Staib-Lasarzik; Thomas Arendt; Adriana del Rey; Kristin Engelhard; Christian Behl; Parvana Hajieva

    2014-01-01

    Oxidative stress is thought to be one of the main mediators of neuronal damage in human neurodegenerative disease. Still, the dissection of causal relationships has turned out to be remarkably difficult. Here, we have analyzed global protein oxidation in terms of carbonylation of membrane proteins and cytoplasmic proteins in three different mammalian species: aged human cortex and cerebellum from patients with or without Alzheimer's disease, mouse cortex and cerebellum from young and old anim...

  19. Does Cell Lineage in the Developing Cerebral Cortex Contribute to its Columnar Organization?

    Science.gov (United States)

    Costa, Marcos R.; Hedin-Pereira, Cecilia

    2010-01-01

    Since the pioneer work of Lorente de Nó, Ramón y Cajal, Brodmann, Mountcastle, Hubel and Wiesel and others, the cerebral cortex has been seen as a jigsaw of anatomic and functional modules involved in the processing of different sets of information. In fact, a columnar distribution of neurons displaying similar functional properties throughout the cerebral cortex has been observed by many researchers. Although it has been suggested that much of the anatomical substrate for such organization would be already specified at early developmental stages, before activity-dependent mechanisms could take place, it is still unclear whether gene expression in the ventricular zone (VZ) could play a role in the development of discrete functional units, such as minicolumns or columns. Cell lineage experiments using replication-incompetent retroviral vectors have shown that the progeny of a single neuroepithelial/radial glial cell in the dorsal telencephalon is organized into discrete radial clusters of sibling excitatory neurons, which have a higher propensity for developing chemical synapses with each other rather than with neighboring non-siblings. Here, we will discuss the possibility that the cell lineage of single neuroepithelial/radial glia cells could contribute for the columnar organization of the neocortex by generating radial columns of sibling, interconnected neurons. Borrowing some concepts from the studies on cell–cell recognition and transcription factor networks, we will also touch upon the potential molecular mechanisms involved in the establishment of sibling-neuron circuits. PMID:20676384

  20. Does cell lineage in the developing cerebral cortex contribute to its columnar organization?

    Directory of Open Access Journals (Sweden)

    Marcos R Costa

    2010-06-01

    Full Text Available Since the pioneer work of Lorente de Nó, Ramón y Cajal, Brodmann, Mountcastle, Hubel and Wiesel and others, the cerebral cortex has been seen as a jigsaw of anatomic and functional modules involved in the processing of different sets of information. In fact, a columnar distribution of neurons displaying similar functional properties throughout the cerebral cortex has been observed by many researchers. Although it has been suggested that much of the anatomical substrate for such organization would be already specified at early developmental stages, before activity-dependent mechanisms could take place, it is still unclear whether gene expression in the ventricular zone could play a role in the development of discrete functional units, such as minicolumns or columns. Cell lineage experiments using replication-incompetent retroviral vectors have shown that the progeny of a single neuroepithelial/radial glial cell in the dorsal telencephalon is organized into discrete radial clusters of sibling excitatory neurons, which have a higher propensity for developing chemical synapses with each other rather than with neighbouring non-siblings. Here, we will discuss the possibility that the cell lineage of single neuroepithelial/radial glia cells could contribute for the columnar organization of the neocortex by generating radial columns of sibling, interconnected neurons. Borrowing some concepts from the studies on cell-cell recognition and transcription factor networks, we will also touch upon the potential molecular mechanisms involved in the establishment of sibling-neuron circuits.

  1. An approach to visual cortex operation: optical neuron model

    OpenAIRE

    Martín Pereda, José Antonio; González Marcos, Ana

    1994-01-01

    Several works have been published in the last years concerning the modelling and implementation of the visual cortex operation. Most of them present simple neurons with just two different responses, namely inhibitory and excitatory. Some of the different types of visual cortex cells are simulated in these configurations.

  2. Multiple distinct subtypes of GABAergic neurons in mouse visual cortex identified by triple immunostaining

    Directory of Open Access Journals (Sweden)

    Yuri Gonchar

    2008-03-01

    Full Text Available The majority of cortical interneurons use GABA (gamma amino butyric acid as inhibitory neurotransmitter. GABAergic neurons are morphologically, connectionally, electrically and chemically heterogeneous. In rat cerebral cortex three distinct groups of GABAergic interneurons have been identifi ed by the expression of parvalbumin (PV, calretinin (CR and somatostatin (SOM. Recent studies in mouse cerebral cortex have revealed a different organization in which the CR and SOM populations are partially overlapping. Because CR and SOM neurons derive from different progenitors located in different embryonic structures, the coexpression of CR + SOM suggests that the chemical differentiation of interneurons is regulated postmitotically. Here, we have taken an important fi rst step towards understanding this process by triple immunostaining mouse visual cortex with a panel of antibodies, which has been used extensively for classifying developing interneurons. We have found at least 13 distinct groups of GABAergic neurons which include PV, CR, SOM, CCK (cholecystokinin, CR + SOM, CR + NPY (neuropeptide Y, CR + VIP (vasointestinal polypeptide, SOM + NPY, SOM + VIP, VIP + ChAT (choline acetyltransferase, CCK + NPY, CR + SOM + NPY and CR + SOM + VIP expressing cells. Triple immunostaining with PV, CR and SOM antibodies during postnatal development further showed that PV is never colocalized with CR and SOM. Importantly, expression of SOM and CR + SOM developed after the percentage of CR cells that do not express SOM has reached the mature level, suggesting that the chemical differentiation of SOM and CR + SOM neurons is a postnatal event, which may be controlled by transcriptional regulation.

  3. Changes in Cerebral Cortex of Children Treated for Medulloblastoma

    International Nuclear Information System (INIS)

    Purpose: Children with medulloblastoma undergo surgery, radiotherapy, and chemotherapy. After treatment, these children have numerous structural abnormalities. Using high-resolution magnetic resonance imaging, we measured the thickness of the cerebral cortex in a group of medulloblastoma patients and a group of normally developing children. Methods and Materials: We obtained magnetic resonance imaging scans and measured the cortical thickness in 9 children after treatment of medulloblastoma. The measurements from these children were compared with the measurements from age- and gender-matched normally developing children previously scanned. For additional comparison, the pattern of thickness change was compared with the cortical thickness maps from a larger group of 65 normally developing children. Results: In the left hemisphere, relatively thinner cortex was found in the perirolandic region and the parieto-occipital lobe. In the right hemisphere, relatively thinner cortex was found in the parietal lobe, posterior superior temporal gyrus, and lateral temporal lobe. These regions of cortical thinning overlapped with the regions of cortex that undergo normal age-related thinning. Conclusion: The spatial distribution of cortical thinning suggested that the areas of cortex that are undergoing development are more sensitive to the effects of treatment of medulloblastoma. Such quantitative methods may improve our understanding of the biologic effects that treatment has on the cerebral development and their neuropsychological implications

  4. A role for PDGF-C/PDGFRα signaling in the formation of the meningeal basement membranes surrounding the cerebral cortex.

    Science.gov (United States)

    Andrae, Johanna; Gouveia, Leonor; Gallini, Radiosa; He, Liqun; Fredriksson, Linda; Nilsson, Ingrid; Johansson, Bengt R; Eriksson, Ulf; Betsholtz, Christer

    2016-01-01

    Platelet-derived growth factor-C (PDGF-C) is one of three known ligands for the tyrosine kinase receptor PDGFRα. Analysis ofPdgfcnull mice has demonstrated roles for PDGF-C in palate closure and the formation of cerebral ventricles, but redundancy with other PDGFRα ligands might obscure additional functions. In search of further developmental roles for PDGF-C, we generated mice that were double mutants forPdgfc(-/-)andPdgfra(GFP/+) These mice display a range of severe phenotypes including spina bifida, lung emphysema, abnormal meninges and neuronal over-migration in the cerebral cortex. We focused our analysis on the central nervous system (CNS), where PDGF-C was identified as a critical factor for the formation of meninges and assembly of the glia limitans basement membrane. We also present expression data onPdgfa,PdgfcandPdgfrain the cerebral cortex and microarray data on cerebral meninges. PMID:26988758

  5. Exercise increases mitochondrial glutamate oxidation in the mouse cerebral cortex.

    Science.gov (United States)

    Herbst, Eric A F; Holloway, Graham P

    2016-07-01

    The present study investigated the impact of acute exercise on stimulating mitochondrial respiratory function in mouse cerebral cortex. Where pyruvate-stimulated respiration was not affected by acute exercise, glutamate respiration was enhanced following the exercise bout. Additional assessment revealed that this affect was dependent on the presence of malate and did not occur when substituting glutamine for glutamate. As such, our results suggest that glutamate oxidation is enhanced with acute exercise through activation of the malate-aspartate shuttle. PMID:27184881

  6. Enhanced metabolic capacity of the frontal cerebral cortex after Pavlovian conditioning.

    Science.gov (United States)

    Bruchey, A K; Gonzalez-Lima, F

    2008-03-18

    While Pavlovian conditioning alters stimulus-evoked metabolic activity in the cerebral cortex, less is known about the effects of Pavlovian conditioning on neuronal metabolic capacity. Pavlovian conditioning may increase prefrontal cortical metabolic capacity, as suggested by evidence of changes in cortical synaptic strengths, and evidence for a shift in memory initially processed in subcortical regions to more distributed prefrontal cortical circuits. Quantitative cytochrome oxidase histochemistry was used to measure cumulative changes in brain metabolic capacity associated with both cued and contextual Pavlovian conditioning in rats. The cued conditioned group received tone-foot-shock pairings to elicit a conditioned freezing response to the tone conditioned stimulus, while the contextually conditioned group received pseudorandom tone-foot-shock pairings in an excitatory context. Untrained control group was handled daily, but did not receive any tone presentations or foot shocks. The cued conditioned group had higher cytochrome oxidase activity in the infralimbic and anterior cingulate cortex, and lower cytochrome oxidase activity in dorsal hippocampus than the other two groups. A significant increase in cytochrome oxidase activity was found in anterior cortical areas (medial, dorsal and lateral frontal cortex; agranular insular cortex; lateral and medial orbital cortex and prelimbic cortex) in both conditioned groups, as compared with the untrained control group. In addition, no differences in cytochrome oxidase activity in the somatosensory regions and the amygdala were detected among all groups. The findings indicate that cued and contextual Pavlovian conditioning induces sustained increases in frontal cortical neuronal metabolic demand resulting in regional enhancement in the metabolic capacity of anterior cortical regions. Enhanced metabolic capacity of these anterior cortical areas after Pavlovian conditioning suggests that the frontal cortex may play a

  7. Serine racemase expression in mouse cerebral cortex after permanent focal cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Li-zhen WANG; Xing-zu ZHU

    2004-01-01

    AIM: To study the alterations of the expressions of serine racemase in C57BL/6 mouse brain after permanent focal cerebral ischemia. METHODS: The mRNA level and the protein level of serine racemase were assayed by semiquantitative reverse transcription polymerase chain reaction (RT-PCR) and Western blot, respectively. The amount of D-serine and L-serine were measured by HPLC. RESULTS: High levels of serine racemase were constitutively expressed in the normal cortex of mouse. At early stage after middle cerebral artery occlusion (MCAO), no significant change in expression of serine racemase was observed in temporoparietal cortex in ipsilateral hemisphere. However,delayed transient decreases of serine racemase in both mRNA and protein levels were detected from d 6 to d 10 after ischemia. Correspondingly, D-serine concentration also declined in the ipsilateral cortex during this period when compared with the D-serine level in the contralateral cortex. CONCLUSION:Delayed decreases in serine racemase expression and D-serine level occurred in the temporoparietal cortex at the late stage after focal cerebral ischemia.

  8. Activity-Dependent Callosal Axon Projections in Neonatal Mouse Cerebral Cortex

    Directory of Open Access Journals (Sweden)

    Yoshiaki Tagawa

    2012-01-01

    Full Text Available Callosal axon projections are among the major long-range axonal projections in the mammalian brain. They are formed during the prenatal and early postnatal periods in the mouse, and their development relies on both activity-independent and -dependent mechanisms. In this paper, we review recent findings about the roles of neuronal activity in callosal axon projections. In addition to the well-documented role of sensory-driven neuronal activity, recent studies using in utero electroporation demonstrated an essential role of spontaneous neuronal activity generated in neonatal cortical circuits. Both presynaptic and postsynaptic neuronal activities are critically involved in the axon development. Studies have begun to reveal intracellular signaling pathway which works downstream of neuronal activity. We also review several distinct patterns of neuronal activity observed in the developing cerebral cortex, which might play roles in activity-dependent circuit construction. Such neuronal activity during the neonatal period can be disrupted by genetic factors, such as mutations in ion channels. It has been speculated that abnormal activity caused by such factors may affect activity-dependent circuit construction, leading to some developmental disorders. We discuss a possibility that genetic mutation in ion channels may impair callosal axon projections through an activity-dependent mechanism.

  9. RTTN Mutations Link Primary Cilia Function to Organization of the Human Cerebral Cortex

    Science.gov (United States)

    Kheradmand Kia, Sima; Verbeek, Elly; Engelen, Erik; Schot, Rachel; Poot, Raymond A.; de Coo, Irenaeus F.M.; Lequin, Maarten H.; Poulton, Cathryn J.; Pourfarzad, Farzin; Grosveld, Frank G.; Brehm, António; de Wit, Marie Claire Y.; Oegema, Renske; Dobyns, William B.; Verheijen, Frans W.; Mancini, Grazia M.S.

    2012-01-01

    Polymicrogyria is a malformation of the developing cerebral cortex caused by abnormal organization and characterized by many small gyri and fusion of the outer molecular layer. We have identified autosomal-recessive mutations in RTTN, encoding Rotatin, in individuals with bilateral diffuse polymicrogyria from two separate families. Rotatin determines early embryonic axial rotation, as well as anteroposterior and dorsoventral patterning in the mouse. Human Rotatin has recently been identified as a centrosome-associated protein. The Drosophila melanogaster homolog of Rotatin, Ana3, is needed for structural integrity of centrioles and basal bodies and maintenance of sensory neurons. We show that Rotatin colocalizes with the basal bodies at the primary cilium. Cultured fibroblasts from affected individuals have structural abnormalities of the cilia and exhibit downregulation of BMP4, WNT5A, and WNT2B, which are key regulators of cortical patterning and are expressed at the cortical hem, the cortex-organizing center that gives rise to Cajal-Retzius (CR) neurons. Interestingly, we have shown that in mouse embryos, Rotatin colocalizes with CR neurons at the subpial marginal zone. Knockdown experiments in human fibroblasts and neural stem cells confirm a role for RTTN in cilia structure and function. RTTN mutations therefore link aberrant ciliary function to abnormal development and organization of the cortex in human individuals. PMID:22939636

  10. Spindle neurons of the human anterior cingulate cortex

    Science.gov (United States)

    Nimchinsky, E. A.; Vogt, B. A.; Morrison, J. H.; Hof, P. R.; Bloom, F. E. (Principal Investigator)

    1995-01-01

    The human anterior cingulate cortex is distinguished by the presence of an unusual cell type, a large spindle neuron in layer Vb. This cell has been noted numerous times in the historical literature but has not been studied with modern neuroanatomic techniques. For instance, details regarding the neuronal class to which these cells belong and regarding their precise distribution along both ventrodorsal and anteroposterior axes of the cingulate gyrus are still lacking. In the present study, morphological features and the anatomic distribution of this cell type were studied using computer-assisted mapping and immunocytochemical techniques. Spindle neurons are restricted to the subfields of the anterior cingulate cortex (Brodmann's area 24), exhibiting a greater density in anterior portions of this area than in posterior portions, and tapering off in the transition zone between anterior and posterior cingulate cortex. Furthermore, a majority of the spindle cells at any level is located in subarea 24b on the gyral surface. Immunocytochemical analysis revealed that the neurofilament protein triple was present in a large percentage of these neurons and that they did not contain calcium-binding proteins. Injections of the carbocyanine dye DiI into the cingulum bundle revealed that these cells are projection neurons. Finally, spindle cells were consistently affected in Alzheimer's disease cases, with an overall loss of about 60%. Taken together, these observations indicate that the spindle cells of the human cingulate cortex represent a morphological subpopulation of pyramidal neurons whose restricted distribution may be associated with functionally distinct areas.

  11. Metabolic effects of perinatal asphyxia in the rat cerebral cortex.

    Science.gov (United States)

    Souza, Samir Khal; Martins, Tiago Leal; Ferreira, Gustavo Dias; Vinagre, Anapaula Sommer; Silva, Roselis Silveira Martins da; Frizzo, Marcos Emilio

    2013-03-01

    We reported previously that intrauterine asphyxia acutely affects the rat hippocampus. For this reason, the early effects of this injury were studied in the cerebral cortex, immediately after hysterectomy (acute condition) or following a recovery period at normoxia (recovery condition). Lactacidemia and glycemia were determined, as well as glycogen levels in the muscle, liver and cortex. Cortical tissue was also used to assay the ATP levels and glutamate uptake. Asphyxiated pups exhibited bluish coloring, loss of movement, sporadic gasping and hypertonia. However, the appearance of the controls and asphyxiated pups was similar at the end of the recovery period. Lactacidemia and glycemia were significantly increased by asphyxia in both the acute and recovery conditions. Concerning muscle and hepatic glycogen, the control group showed significantly higher levels than the asphyxic group in the acute condition and when compared with groups of the recovery period. In the recovery condition, the control and asphyxic groups showed similar glycogen levels. However, in the cortex, the control groups showed significantly higher glycogen levels than the asphyxic group, in both the acute and recovery conditions. In the cortical tissue, asphyxia reduced ATP levels by 70 % in the acute condition, but these levels increased significantly in asphyxic pups after the recovery period. Asphyxia did not affect glutamate transport in the cortex of both groups. Our results suggest that the cortex uses different energy resources to restore ATP after an asphyxia episode followed by a reperfusion period. This strategy could sustain the activity of essential energy-dependent mechanisms. PMID:23196669

  12. Effect of orphanin FQ and morphine on sodium channel current in somatosensory area of rat cerebral cortex

    Institute of Scientific and Technical Information of China (English)

    Lei Yang; Yurong Li; Shuwei Jia; Yunhong Zhang; Lanwei Cui; Lihui Qu

    2007-01-01

    BACKGROUND: Some experiments have demonstrated that injecting orphanin FQ (OFQ) into lateral ventricle, which can obviously decrease the pain threshold. It is indicated that OFQ is an anti-opiate substance. However, whether OFQ has effects on sensory neuron ion channel in cerebral cortex needs to be further studied.OBJECTIVE: To investigate the effects of OFQ, morphine or their combination on sodium channel current of somatosensory neurons in rat cerebral cortex.DESIGN: Repeated measurement trial.SETTING: Department of Physiology, Harbin Medical University.MATERIALS: Fifty healthy Wistar rats, aged 12-16 days, of either gender, were provided by the Experimental Animal Center, Second Hospital Affiliated to Harbin Medical University. OFQ was purchased from Sigma-Aldrich Company, and morphine was provided by the Shenyang First Pharmaceutical Factory.PC2C patch clamp amplifier and LabmasterTLlwere purchased from Yibo Life Science Instrument Co.,Ltd.of Huazhong University of Science and Techgnology.METHODS: This experiment was carried out in the Department of Physiology (provincial laboratory),Harbin Medical University between January 2005 and May 2006. Cortical neurons were acutely isolated from rats, and prepared into cell suspension following culture. ①Sodium channel current of somatosensory neurons in rat cerebral cortex was recorded before and after administration by whole-cell Patch clamptechnique after 50 nmol/L OFQ being added to extracellular fluid.②The amplitude of sodium channel current of somatosensory neurons in rat cerebral cortex was recorded before and after administration by the same method after 20 I mol/L morphine being added to extracellular fluid, and then the change of sodium channel current was recorded after 50 nmol/L OFQ being added.MAIN OUTCOME MEASURES: The amplitude of sodium channel current of somatosensory neurons in rat cerebral cortex following the administration of OFQ, morphine separately or their combination

  13. Occurrence of new neurons in the piriform cortex

    Directory of Open Access Journals (Sweden)

    Ti-Fei eYuan

    2015-01-01

    Full Text Available Adult neurogenesis has been well studied in hippocampus and subventricular zone; while this is much less appreciated in other brain regions, including amygdala, hypothalamus and piriform cortex. The present review aims at summarizing recent advances on the occurrence of new neurons in the piriform cortex, their potential origin and migration route from the subventricular zone. We further discuss the relevant implications in olfactory dysfunction accompanying the neuro-degenerative diseases.

  14. Small scale module of the rat granular retrosplenial cortex: an example of minicolumn-like structure of the cerebral cortex

    Directory of Open Access Journals (Sweden)

    Noritaka eIchinohe

    2012-01-01

    Full Text Available Structures associated with the small scale module called minicolumn can be observed frequently in the cerebral cortex. However, the description of functional characteristics remains obscure. A significant confounding factor is the marked variability both in the definition of a minicolumn and in the diagnostic markers for identifying a minicolumn (see for review, Jones, 2000, DeFelipe et al., 2003; Rockland and Ichinohe, 2004. Within a minicolumn, cell columns are easily visualized by conventional Nissl staining. Dendritic bundles were first discovered with Golgi methods, but are more easily seen with MAP2-immunohistochemisty. Myelinated axon bundles can be seen by Tau-immunohistochemistry or myelin staining. Axon bundles of double bouquet cell can be seen by calbindin-immunohistochemistry. The spatial interrelationship among these morphological elements is more complex than expected and is neither clear nor unanimously agreed upon. In this review, I would like to focus first on the minicolumnar structure found in layers 1 and 2 of the rat granular retrosplenial cortex (GRS. This modular structure was first discovered as a combination of prominent apical dendritic bundles from layer 2 pyramidal neurons and spatially-matched thalamocortical patchy inputs (Wyss et al., 2000. Further examination showed more intricate components of this modular structure, which will be reviewed in this paper. Second, the postnatal development of this structure and potential molecular players for its formation will be reviewed. Thirdly, I will discuss how this modular organization is transformed in mutant rodents with a disorganized layer structure in the cerebral cortex (i.e., reeler mouse and Shaking Rat Kawasaki. Lastly, the potential significance of this type of module will be discussed.

  15. Neuronal correlate of pictorial short-term memory in the primate temporal cortexYasushi Miyashita

    Science.gov (United States)

    Miyashita, Yasushi; Chang, Han Soo

    1988-01-01

    It has been proposed that visual-memory traces are located in the temporal lobes of the cerebral cortex, as electric stimulation of this area in humans results in recall of imagery1. Lesions in this area also affect recognition of an object after a delay in both humans2,3 and monkeys4-7 indicating a role in short-term memory of images8. Single-unit recordings from the temporal cortex have shown that some neurons continue to fire when one of two or four colours are to be remembered temporarily9. But neuronal responses selective to specific complex objects10-18 , including hands10,13 and faces13,16,17, cease soon after the offset of stimulus presentation10-18. These results led to the question of whether any of these neurons could serve the memory of complex objects. We report here a group of shape-selective neurons in an anterior ventral part of the temporal cortex of monkeys that exhibited sustained activity during the delay period of a visual short-term memory task. The activity was highly selective for the pictorial information to be memorized and was independent of the physical attributes such as size, orientation, colour or position of the object. These observations show that the delay activity represents the short-term memory of the categorized percept of a picture.

  16. Network and external perturbation induce burst synchronisation in cat cerebral cortex

    Science.gov (United States)

    Lameu, Ewandson L.; Borges, Fernando S.; Borges, Rafael R.; Batista, Antonio M.; Baptista, Murilo S.; Viana, Ricardo L.

    2016-05-01

    The brain of mammals are divided into different cortical areas that are anatomically connected forming larger networks which perform cognitive tasks. The cat cerebral cortex is composed of 65 areas organised into the visual, auditory, somatosensory-motor and frontolimbic cognitive regions. We have built a network of networks, in which networks are connected among themselves according to the connections observed in the cat cortical areas aiming to study how inputs drive the synchronous behaviour in this cat brain-like network. We show that without external perturbations it is possible to observe high level of bursting synchronisation between neurons within almost all areas, except for the auditory area. Bursting synchronisation appears between neurons in the auditory region when an external perturbation is applied in another cognitive area. This is a clear evidence that burst synchronisation and collective behaviour in the brain might be a process mediated by other brain areas under stimulation.

  17. Neuropeptide Y protects cerebral cortical neurons by regulating microglial immune function

    Institute of Scientific and Technical Information of China (English)

    Qijun Li; Changzheng Dong; Wenling Li; Wei Bu; Jiang Wu; Wenqing Zhao

    2014-01-01

    Neuropeptide Y has been shown to inhibit the immunological activity of reactive microglia in the rat cerebral cortex, to reduce N-methyl-D-aspartate current (INMDA) in cortical neurons, and protect neurons. In this study, after primary cultured microglia from the cerebral cortex of rats were treated with lipopolysaccharide, interleukin-1β and tumor necrosis factor-α levels in the cell culture medium increased, and mRNA expression of these cytokines also increased. After primary cultured cortical neurons were incubated with the lipopolysaccharide-treated microg-lial conditioned medium, peak INMDA in neurons increased. These effects of lipopolysaccharide were suppressed by neuropeptide Y. After addition of the neuropeptide Y Y1 receptor antago-nist BIBP3226, the effects of neuropeptide Y completely disappeared. These results suggest that neuropeptide Y prevents excessive production of interleukin-1β and tumor necrosis factor-α by inhibiting microglial reactivity. This reduces INMDA in rat cortical neurons, preventing excitotoxic-ity, thereby protecting neurons.

  18. Alterations of the cerebral cortex in sporadic small vessel disease: A systematic review of in vivo MRI data.

    Science.gov (United States)

    Peres, Roxane; De Guio, François; Chabriat, Hugues; Jouvent, Eric

    2016-04-01

    Cerebral small vessel diseases of the brain are a major determinant of cognitive impairment in the elderly. In small vessel diseases, the most easily identifiable lesions, both at post-mortem evaluation and magnetic resonance imaging, lie in subcortical areas. However, recent results obtained post-mortem, particularly in severe cases, have highlighted the burden of cortex lesions such as microinfarcts and diffuse neuronal loss. The recent development of image post-processing methods allows now assessing in vivo multiple aspects of the cerebral cortex. This systematic review aimed to analyze in vivo magnetic resonance imaging studies evaluating cortex alterations at different stages of small vessel diseases. Studies assessing the relationships between small vessel disease magnetic resonance imaging markers obtained at the subcortical level and cortex estimates were reviewed both in community-dwelling elderly and in patients with symptomatic small vessel diseases. Thereafter, studies analyzing cortex estimates in small vessel disease patients compared with healthy subjects were evaluated. The results support that important cortex alterations develop along the course of small vessel diseases independently of concomitant neurodegenerative processes. Easy detection and quantification of cortex changes in small vessel diseases as well as understanding their underlying mechanisms are challenging tasks for better understanding cognitive decline in small vessel diseases. PMID:26787108

  19. Neuronal injury in the motor cortex after chronic stroke and lower limb motor impairment:a voxel-based lesion symptom mapping study

    Institute of Scientific and Technical Information of China (English)

    Alexandria M. Reynolds; Denise M. Peters; Jennifer M. C. Vendemia; Lenwood P. Smith; Raymond C. Sweet; Gordon C. Baylis; Debra Krotish; Stacy L Fritz

    2014-01-01

    Many studies have examined motor impairments using voxel-based lesion symptom mapping, but few are reported regarding the corresponding relationship between cerebral cortex injury and lower limb motor impairment analyzed using this technique. This study correlated neuro-nal injury in the cerebral cortex of 16 patients with chronic stroke based on a voxel-based lesion symptom mapping analysis. Neuronal injury in the corona radiata, caudate nucleus and putamen of patients with chronic stroke could predict walking speed. The behavioral measure scores were consistent with motor deifcits expected after damage to the cortical motor system due to stroke. These ifndings suggest that voxel-based lesion symptom mapping may provide a more accurate prognosis of motor recovery from chronic stroke according to neuronal injury in cerebral motor cortex.

  20. Expression of bone morphogenetic protein 7 in the cerebral cortex of rats after ischemic-hypoxic injury

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    cerebral ischemia, expression of BMP-7 in cerebral cortex on ischemic side was stronger than that on non-ischemic side in adult rats; meanwhile, numbers of cell expression were increased. However, expression of BMP-7 was not detected in bilateral cerebral cortex of adult rats in both control group and sham operation group. ② After hypoxia of cerebral cortex in primary culture, positive products of BMP-7 were observed in plasma of neuron, but expression of BMP-7 was not found in normal cerebral cortex.CONCLUSION: Endogenous BMP-7 has protective effects on nerve tissue induced by ischemic-hypoxic injury.

  1. Decreased GABA receptor in the cerebral cortex of epileptic rats: effect of Bacopa monnieri and Bacoside-A

    Directory of Open Access Journals (Sweden)

    Mathew Jobin

    2012-02-01

    Full Text Available Abstact Background Gamma amino butyric acid (GABA, the principal inhibitory neurotransmitter in the cerebral cortex, maintains the inhibitory tones that counter balances neuronal excitation. When this balance is perturbed, seizures may ensue. Methods In the present study, alterations of the general GABA, GABAA and GABAB receptors in the cerebral cortex of the epileptic rat and the therapeutic application of Bacopa monnieri were investigated. Results Scatchard analysis of [3H]GABA, [3H]bicuculline and [3H]baclofen in the cerebral cortex of the epileptic rat showed significant decrease in Bmax (P Aά1, GABAAγ, GABAAδ, GABAB and GAD where down regulated (P Aά5 subunit and Cyclic AMP responsible element binding protein were up regulated. Confocal imaging study confirmed the decreased GABA receptors in epileptic rats. Epileptic rats have deficit in radial arm and Y maze performance. Conclusions Bacopa monnieri and Bacoside-A treatment reverses epilepsy associated changes to near control suggesting that decreased GABA receptors in the cerebral cortex have an important role in epileptic occurrence; Bacopa monnieri and Bacoside-A have therapeutic application in epilepsy management.

  2. Mapping the human cerebral cortex using 3-D medial manifolds

    Science.gov (United States)

    Szekely, Gabor; Brechbuehler, Christian; Kuebler, Olaf; Ogniewicz, Robert; Budinger, Thomas F.

    1992-09-01

    Novel imaging technologies provide a detailed look at structure and function of the tremendously complex and variable human brain. Optimal exploitation of the information stored in the rapidly growing collection of acquired and segmented MRI data calls for robust and reliable descriptions of the individual geometry of the cerebral cortex. A mathematical description and representation of 3-D shape, capable of dealing with form of variable appearance, is at the focus of this paper. We base our development on the Medial Axis Transformation (MAT) customarily defined in 2-D although the concept generalizes to any number of dimensions. Our implementation of the 3-D MAT combines full 3-D Voronoitesselation generated by the set of all border points with regularization procedures to obtain geometrically and topologically correct medial manifolds. The proposed algorithm was tested on synthetic objects and has been applied to 3-D MRI data of 1 mm isotropic resolution to obtain a description of the sulci in the cerebral cortex. Description and representation of the cortical anatomy is significant in clinical applications, medical research, and instrumentation developments.

  3. A multi-modal parcellation of human cerebral cortex.

    Science.gov (United States)

    Glasser, Matthew F; Coalson, Timothy S; Robinson, Emma C; Hacker, Carl D; Harwell, John; Yacoub, Essa; Ugurbil, Kamil; Andersson, Jesper; Beckmann, Christian F; Jenkinson, Mark; Smith, Stephen M; Van Essen, David C

    2016-08-11

    Understanding the amazingly complex human cerebral cortex requires a map (or parcellation) of its major subdivisions, known as cortical areas. Making an accurate areal map has been a century-old objective in neuroscience. Using multi-modal magnetic resonance images from the Human Connectome Project (HCP) and an objective semi-automated neuroanatomical approach, we delineated 180 areas per hemisphere bounded by sharp changes in cortical architecture, function, connectivity, and/or topography in a precisely aligned group average of 210 healthy young adults. We characterized 97 new areas and 83 areas previously reported using post-mortem microscopy or other specialized study-specific approaches. To enable automated delineation and identification of these areas in new HCP subjects and in future studies, we trained a machine-learning classifier to recognize the multi-modal 'fingerprint' of each cortical area. This classifier detected the presence of 96.6% of the cortical areas in new subjects, replicated the group parcellation, and could correctly locate areas in individuals with atypical parcellations. The freely available parcellation and classifier will enable substantially improved neuroanatomical precision for studies of the structural and functional organization of human cerebral cortex and its variation across individuals and in development, aging, and disease. PMID:27437579

  4. Monoclonal antibody identification of subpopulations of cerebral cortical neurons affected in Alzheimer's disease

    International Nuclear Information System (INIS)

    Neuronal degeneration is one of the hallmarks of Alzheimer's disease (AD). Given the paucity of molecular markers available for the identification of neuronal subtypes, the specificity of neuronal loss within the cerebral cortex has been difficult to evaluate. With a panel of four monoclonal antibodies (mAbs) applied to central nervous system tissues from AD patients, the authors have immunocytochemically identified a population of vulnerable cortical neurons; a subpopulation of pyramidal neurons is recognized by mAbs 3F12 and 44.1 in the hippocampus and neocortex, and clusters of multipolar neurons in the entorhinal cortex reactive with mAb 44.1 show selective degeneration. Closely adjacent stellate-like neurons in these regions, identified by mAb 6A2, show striking preservation in AD. The neurons recognized by mAbs 3F12 and 44.1 do not comprise a single known neurotransmitter system. mAb 3A4 identifies a phosphorylated antigen that is undetectable in normal brain but accumulates early in the course of AD in somas of vulnerable neurons. Antigen 3A4 is distinct from material reactive with thioflavin S or antibody generated against paired helical filaments. Initially, antigen 3A4 is localized to neurons in the entorhinal cortex and subiculum, later in the association neocortex, and, ultimately in cases of long duration, in primary sensory cortical regions. mAb 3F12 recognizes multiple bands of immunoblots of homogenates of normal and AD cortical tissues, whereas mAb 3A4 does not bind to immunoblots containing neurofilament proteins or brain homogenates from AD patients. Ultrastructurally, antigen 3A4 is localized to paired-helical filaments. Using these mAbs, further molecular characterization of the affected cortical neurons is now possible

  5. Dab2IP Regulates Neuronal Positioning, Rap1 Activity and Integrin Signaling in the Developing Cortex.

    Science.gov (United States)

    Qiao, Shuhong; Homayouni, Ramin

    2015-01-01

    Dab2IP (DOC-2/DAB2 interacting protein) is a GTPase-activating protein which is involved in various aspects of brain development in addition to its roles in tumor formation and apoptosis in other systems. In this study, we carefully examined the expression profile of Dab2IP and investigated its physiological role during brain development using a Dab2IP-knockdown (KD) mouse model created by retroviral insertion of a LacZ-encoding gene-trapping cassette. LacZ staining revealed that Dab2IP is expressed in the ventricular zone as well as the cortical plate and the intermediate zone. Immunohistochemical analysis showed that Dab2IP protein is localized in the leading process and proximal cytoplasmic regions of migrating neurons in the intermediate zone. Bromodeoxyuridine birth dating experiments in combination with immunohistochemical analysis using layer-specific markers showed that Dab2IP is important for proper positioning of a subset of layer II-IV neurons in the developing cortex. Notably, neuronal migration was not completely disrupted in the cerebral cortex of Dab2IP-KD mice and disruption of migration was not strictly layer specific. Previously, we found that Dab2IP regulates multipolar transition in cortical neurons. Others have shown that Rap1 regulates the transition from multipolar to bipolar morphology in migrating postmitotic neurons through N-cadherin signaling and somal translocation in the superficial layer of the cortical plate through integrin signaling. Therefore, we examined whether Rap1 and integrin signaling were affected in Dab2IP-KD brains. We found that Dab2IP-KD resulted in higher levels of activated Rap1 and integrin in the developing cortex. Taken together, our results suggest that Dab2IP plays an important role in the migration and positioning of a subpopulation of later-born (layers II-IV) neurons, likely through the regulation of Rap1 and integrin signaling. PMID:25721469

  6. Point application with Angong Niuhuang sticker protects hippocampal and cortical neurons in rats with cerebral ischemia

    Directory of Open Access Journals (Sweden)

    Dong-shu Zhang

    2015-01-01

    Full Text Available Angong Niuhuang pill, a Chinese materia medica preparation, can improve neurological functions after acute ischemic stroke. Because of its inconvenient application and toxic components (Cinnabaris and Realgar, we used transdermal enhancers to deliver Angong Niuhuang pill by modern technology, which expanded the safe dose range and clinical indications. In this study, Angong Niuhuang stickers administered at different point application doses (1.35, 2.7, and 5.4 g/kg were administered to the Dazhui (DU14, Qihai (RN6 and Mingmen (DU4 of rats with chronic cerebral ischemia, for 4 weeks. The Morris water maze was used to determine the learning and memory ability of rats. Hematoxylin-eosin staining and Nissl staining were used to observe neuronal damage of the cortex and hippocampal CA1 region in rats with chronic cerebral ischemia. The middle- and high-dose point application of Angong Niuhuang stickers attenuated neuronal damage in the cortex and hippocampal CA1 region, and improved the memory of rats with chronic cerebral ischemia with an efficacy similar to interventions by electroacupuncture at Dazhui (DU14, Qihai (RN6 and Mingmen (DU4. Our experimental findings indicate that point application with Angong Niuhuang stickers can improve cognitive function after chronic cerebral ischemia in rats and is neuroprotective with an equivalent efficacy to acupuncture.

  7. Neuronal correlate of visual associative long-term memory in the primate temporal cortex

    Science.gov (United States)

    Miyashita, Yasushi

    1988-10-01

    In human long-term memory, ideas and concepts become associated in the learning process1. No neuronal correlate for this cognitive function has so far been described, except that memory traces are thought to be localized in the cerebral cortex; the temporal lobe has been assigned as the site for visual experience because electric stimulation of this area results in imagery recall,2 and lesions produce deficits in visual recognition of objects3-9. We previously reported that in the anterior ventral temporal cortex of monkeys, individual neurons have a sustained activity that is highly selective for a few of the 100 coloured fractal patterns used in a visual working-memory task10. Here I report the development of this selectivity through repeated trials involving the working memory. The few patterns for which a neuron was conjointly selective were frequently related to each other through stimulus-stimulus association imposed during training. The results indicate that the selectivity acquired by these cells represents a neuronal correlate of the associative long-term memory of pictures.

  8. Neurons controlling voluntary vocalization in the macaque ventral premotor cortex.

    Directory of Open Access Journals (Sweden)

    Gino Coudé

    Full Text Available The voluntary control of phonation is a crucial achievement in the evolution of speech. In humans, ventral premotor cortex (PMv and Broca's area are known to be involved in voluntary phonation. In contrast, no neurophysiological data are available about the role of the oro-facial sector of nonhuman primates PMv in this function. In order to address this issue, we recorded PMv neurons from two monkeys trained to emit coo-calls. Results showed that a population of motor neurons specifically fire during vocalization. About two thirds of them discharged before sound onset, while the remaining were time-locked with it. The response of vocalization-selective neurons was present only during conditioned (voluntary but not spontaneous (emotional sound emission. These data suggest that the control of vocal production exerted by PMv neurons constitutes a newly emerging property in the monkey lineage, shedding light on the evolution of phonation-based communication from a nonhuman primate species.

  9. Tyrosine promotes oxidative stress in cerebral cortex of young rats.

    Science.gov (United States)

    Sgaravatti, Angela M; Vargas, Bethânia A; Zandoná, Bernardo R; Deckmann, Kátia B; Rockenbach, Francieli J; Moraes, Tarsila B; Monserrat, José M; Sgarbi, Mirian B; Pederzolli, Carolina D; Wyse, Angela T S; Wannmacher, Clóvis M D; Wajner, Moacir; Dutra-Filho, Carlos Severo

    2008-10-01

    Tyrosine accumulates in inborn errors of tyrosine catabolism, especially in tyrosinemia type II, where tyrosine levels are highly elevated in tissues and physiological fluids of affected patients. In tyrosinemia type II, high levels of tyrosine are correlated with eyes, skin and central nervous system disturbances. Considering that the mechanisms of brain damage in these disorders are poorly known, in the present study, we investigated whether oxidative stress is elicited by l-tyrosine in cerebral cortex homogenates of 14-day-old Wistar rats. The in vitro effect of 0.1-4.0mM l-tyrosine was studied on the following oxidative stress parameters: total radical-trapping antioxidant potential (TRAP), total antioxidant reactivity (TAR), ascorbic acid content, reduced glutathione (GSH) content, spontaneous chemiluminescence, thiobarbituric acid-reactive substances (TBA-RS), thiol-disulfide redox state (SH/SS ratio), protein carbonyl content, formation of DNA-protein cross-links, and the activities of the enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glucose-6-phosphate dehydrogenase (G6PDH). TRAP, TAR, ascorbic acid content, SH/SS ratio and CAT activity were significantly diminished, while formation of DNA-protein cross-link was significantly enhanced by l-tyrosine in vitro. In contrast, l-tyrosine did not affect the other parameters of oxidative stress evaluated. These results indicate that l-tyrosine decreases enzymatic and non-enzymatic antioxidant defenses, changes the redox state and stimulates DNA damage in cerebral cortex of young rats in vitro. This suggests that oxidative stress may represent a pathophysiological mechanism in tyrosinemic patients, in which this amino acid accumulates.

  10. Exposure to brominated flame retardant PBDE-99 affects cytoskeletal protein expression in the neonatal mouse cerebral cortex

    DEFF Research Database (Denmark)

    Alm, Henrik; Kultima, Kim; Scholz, Birger;

    2008-01-01

    Polybrominated diphenyl ethers (PBDEs) are environmental contaminants found in human and animal tissues worldwide. Neonatal exposure to the flame retardant 2,2', 4,4',5-pentabromodiphenyl ether (PBDE-99) disrupts normal brain development in mice, and results in disturbed spontaneous behavior in the...... adult. The mechanisms underlying the late effects of early exposure are not clear. To gain insight into the initial neurodevelopmental damage inflicted by PBDE-99, we investigated the short-term effects of PBDE-99 on protein expression in the developing cerebral cortex of neonatal mice, and the......-3 activity. These results indicate that the permanent neurological damage induced by PBDE-99 during the brain growth spurt involve detrimental effects on cytoskeletal regulation and neuronal maturation in the developing cerebral cortex....

  11. Neuron Types in the Presumptive Primary Somatosensory Cortex of the Florida Manatee (Trichechus manatus latirostris).

    Science.gov (United States)

    Reyes, Laura D; Stimpson, Cheryl D; Gupta, Kanika; Raghanti, Mary Ann; Hof, Patrick R; Reep, Roger L; Sherwood, Chet C

    2015-01-01

    Within afrotherians, sirenians are unusual due to their aquatic lifestyle, large body size and relatively large lissencephalic brain. However, little is known about the neuron type distributions of the cerebral cortex in sirenians within the context of other afrotherians and aquatic mammals. The present study investigated two cortical regions, dorsolateral cortex area 1 (DL1) and cluster cortex area 2 (CL2), in the presumptive primary somatosensory cortex (S1) in Florida manatees (Trichechus manatus latirostris) to characterize cyto- and chemoarchitecture. The mean neuron density for both cortical regions was 35,617 neurons/mm(3) and fell within the 95% prediction intervals relative to brain mass based on a reference group of afrotherians and xenarthrans. Densities of inhibitory interneuron subtypes labeled against calcium-binding proteins and neuropeptide Y were relatively low compared to afrotherians and xenarthrans and also formed a small percentage of the overall population of inhibitory interneurons as revealed by GAD67 immunoreactivity. Nonphosphorylated neurofilament protein-immunoreactive (NPNFP-ir) neurons comprised a mean of 60% of neurons in layer V across DL1 and CL2. DL1 contained a higher percentage of NPNFP-ir neurons than CL2, although CL2 had a higher variety of morphological types. The mean percentage of NPNFP-ir neurons in the two regions of the presumptive S1 were low compared to other afrotherians and xenarthrans but were within the 95% prediction intervals relative to brain mass, and their morphologies were comparable to those found in other afrotherians and xenarthrans. Although this specific pattern of neuron types and densities sets the manatee apart from other afrotherians and xenarthrans, the manatee isocortex does not appear to be explicitly adapted for an aquatic habitat. Many of the features that are shared between manatees and cetaceans are also shared with a diverse array of terrestrial mammals and likely represent highly conserved

  12. Morphological Heterogeneity of Layer VI Neurons in Mouse Barrel Cortex

    OpenAIRE

    Chen, Chia-Chien; Abrams, Svetlana; Pinhas, Alex; Brumberg, Joshua C.

    2009-01-01

    Understanding the basic neuronal building blocks of the neocortex is a necessary first step toward comprehending the composition of cortical circuits. Neocortical layer VI is the most morphologically diverse layer and plays a pivotal role in gating information to the cortex via its feedback connection to the thalamus and other ipsilateral and callosal corticocortical connections. The heterogeneity of function within this layer is presumably linked to its varied morphological composition. Howe...

  13. Embedding Task-Based Neural Models into a Connectome-Based Model of the Cerebral Cortex

    Science.gov (United States)

    Ulloa, Antonio; Horwitz, Barry

    2016-01-01

    A number of recent efforts have used large-scale, biologically realistic, neural models to help understand the neural basis for the patterns of activity observed in both resting state and task-related functional neural imaging data. An example of the former is The Virtual Brain (TVB) software platform, which allows one to apply large-scale neural modeling in a whole brain framework. TVB provides a set of structural connectomes of the human cerebral cortex, a collection of neural processing units for each connectome node, and various forward models that can convert simulated neural activity into a variety of functional brain imaging signals. In this paper, we demonstrate how to embed a previously or newly constructed task-based large-scale neural model into the TVB platform. We tested our method on a previously constructed large-scale neural model (LSNM) of visual object processing that consisted of interconnected neural populations that represent, primary and secondary visual, inferotemporal, and prefrontal cortex. Some neural elements in the original model were “non-task-specific” (NS) neurons that served as noise generators to “task-specific” neurons that processed shapes during a delayed match-to-sample (DMS) task. We replaced the NS neurons with an anatomical TVB connectome model of the cerebral cortex comprising 998 regions of interest interconnected by white matter fiber tract weights. We embedded our LSNM of visual object processing into corresponding nodes within the TVB connectome. Reciprocal connections between TVB nodes and our task-based modules were included in this framework. We ran visual object processing simulations and showed that the TVB simulator successfully replaced the noise generation originally provided by NS neurons; i.e., the DMS tasks performed with the hybrid LSNM/TVB simulator generated equivalent neural and fMRI activity to that of the original task-based models. Additionally, we found partial agreement between the functional

  14. Embedding Task-Based Neural Models into a Connectome-Based Model of the Cerebral Cortex.

    Science.gov (United States)

    Ulloa, Antonio; Horwitz, Barry

    2016-01-01

    A number of recent efforts have used large-scale, biologically realistic, neural models to help understand the neural basis for the patterns of activity observed in both resting state and task-related functional neural imaging data. An example of the former is The Virtual Brain (TVB) software platform, which allows one to apply large-scale neural modeling in a whole brain framework. TVB provides a set of structural connectomes of the human cerebral cortex, a collection of neural processing units for each connectome node, and various forward models that can convert simulated neural activity into a variety of functional brain imaging signals. In this paper, we demonstrate how to embed a previously or newly constructed task-based large-scale neural model into the TVB platform. We tested our method on a previously constructed large-scale neural model (LSNM) of visual object processing that consisted of interconnected neural populations that represent, primary and secondary visual, inferotemporal, and prefrontal cortex. Some neural elements in the original model were "non-task-specific" (NS) neurons that served as noise generators to "task-specific" neurons that processed shapes during a delayed match-to-sample (DMS) task. We replaced the NS neurons with an anatomical TVB connectome model of the cerebral cortex comprising 998 regions of interest interconnected by white matter fiber tract weights. We embedded our LSNM of visual object processing into corresponding nodes within the TVB connectome. Reciprocal connections between TVB nodes and our task-based modules were included in this framework. We ran visual object processing simulations and showed that the TVB simulator successfully replaced the noise generation originally provided by NS neurons; i.e., the DMS tasks performed with the hybrid LSNM/TVB simulator generated equivalent neural and fMRI activity to that of the original task-based models. Additionally, we found partial agreement between the functional

  15. Effect of acute and repeated restraint stress on glucose oxidation to CO2 in hippocampal and cerebral cortex slices

    Directory of Open Access Journals (Sweden)

    Torres I.L.S.

    2001-01-01

    Full Text Available It has been suggested that glucocorticoids released during stress might impair neuronal function by decreasing glucose uptake by hippocampal neurons. Previous work has demonstrated that glucose uptake is reduced in hippocampal and cerebral cortex slices 24 h after exposure to acute stress, while no effect was observed after repeated stress. Here, we report the effect of acute and repeated restraint stress on glucose oxidation to CO2 in hippocampal and cerebral cortex slices and on plasma glucose and corticosterone levels. Male adult Wistar rats were exposed to restraint 1 h/day for 50 days in the chronic model. In the acute model there was a single exposure. Immediately or 24 h after stress, the animals were sacrificed and the hippocampus and cerebral cortex were dissected, sliced, and incubated with Krebs buffer, pH 7.4, containing 5 mM glucose and 0.2 µCi D-[U-14C] glucose. CO2 production from glucose was estimated. Trunk blood was also collected, and both corticosterone and glucose were measured. The results showed that corticosterone levels after exposure to acute restraint were increased, but the increase was smaller when the animals were submitted to repeated stress. Blood glucose levels increased after both acute and repeated stress. However, glucose utilization, measured as CO2 production in hippocampal and cerebral cortex slices, was the same in stressed and control groups under conditions of both acute and chronic stress. We conclude that, although stress may induce a decrease in glucose uptake, this effect is not sufficient to affect the energy metabolism of these cells.

  16. [The modulation of cerebral cortex and subcortical nuclei on NRM and their role in acupuncture analgesia].

    Science.gov (United States)

    Liu, X

    1996-01-01

    The vast research have demonstrated that the acupuncture analgesia is effected through a physiological mechanism brought about by the nervous system, particularly the central nervous system. We combined the acupuncture effects and theory of channels and collaterals with the new advance of pain neurophysiology, and centred attention on nucleus raphe magnus (NRM), that is one of the origins of the important descending inhibitory pathways of the intrinsic analgesic systems in brain. The unit discharges of NRM neurons and their nociceptors/ph responses were recorded extracellularly with glass microelectrode at 1495 neurons on 634 wastar rats. The modulation of cerebral cortex, the head of N. caudatum (NCa), N. Accumbens (N. Ac), N lateral habenular (NHa) and Periaquaeductal gray matter (PAG) on NRM and their role in acupuncture analgesia were studied by central locational stimulation, lesion and microinjection. The result were as follows: 1. The most NRM neurons could respond to noxious stimulation of tail tip with increasing or decreasing firing rate. Electroacupuncture (EA) at "Zusanli" could activate the NRM neuron, increasing discharges, and inhibit their nociceptive responses, producing analgesia. 2. The activity of NRM neuron was modulated by PAG, NAc, and NCa. Stimulation at one of them can activate neuron of NRM, increasing firing rate, and induce analgesia. When the lesion or microinjection naloxone were made in PAG, NAc or NCa, EA analgesia could be weakened or lost, even the nociceptive responses might be increased. It is suggest that the nuclei participated in EA analgesia with their endogenous opiate like substance, and were playing an important role. It is also indicated that the electroacupuncture was used on the patients with some nuclei lesion or pathological changes should be careful to avoid making patients feel more painful. 3. Somatosensory area II (Sm II) of cerebral cortex participated in EA analgesia. The analgesic effects of EA at "Zusanli

  17. The complexity of the calretinin-expressing progenitors in the human cerebral cortex

    Directory of Open Access Journals (Sweden)

    Nevena V Radonjic

    2014-08-01

    Full Text Available The complex structure and function of the cerebral cortex critically depend on the balance of excitation and inhibition provided by the pyramidal projection neurons and GABAergic interneurons, respectively. The calretinin-expressing (CalR+ cell is a subtype of GABAergic cortical interneurons that is more prevalent in humans than in rodents. In rodents, CalR+ interneurons originate in the caudal ganglionic eminence (CGE from Gsx2+ progenitors, but in humans it has been suggested that a subpopulation of CalR+ cells can also be generated in the cortical ventricular/subventricular zone (VZ/SVZ. The progenitors for cortically generated CalR+ subpopulation in primates are not yet characterized. Hence, the aim of this study was to identify patterns of expression of the transcription factors (TFs that commit cortical stem cells to the CalR fate, with a focus on Gsx2. First, we studied the expression of Gsx2 and its downstream effectors, Ascl1 and Sp8 in the cortical regions of the fetal human forebrain at midgestation. Next, we established that a subpopulation of cells expressing these TFs are proliferating in the cortical SVZ, and can be co-labeled with CalR. The presence and proliferation of Gsx2+ cells, not only in the ventral telencephalon (GE as previously reported, but also in the cerebral cortex suggests cortical origin of a subpopulation of CalR+ neurons in humans. In vitro treatment of human cortical progenitors with Sonic hedgehog (Shh, an important morphogen in the specification of interneurons, decreased levels of Ascl1 and Sp8 proteins, but did not affect Gsx2 levels. Taken together, our ex-vivo and in vitro results on human fetal brain suggest complex endogenous and exogenous regulation of TFs implied in the specification of different subtypes of CalR+ cortical interneurons.

  18. Neuroprotection of 17β-estradiol on neurons and effects on expression of BDNF in cerebral cortex of rat after forebrain ischemia reperfusion%17β-雌二醇对前脑缺血-再灌注大鼠大脑皮层神经元保护作用及BDNF表达的影响

    Institute of Scientific and Technical Information of China (English)

    李正仪; 李志伟; 郭金涛

    2011-01-01

    Objective To observe the neuroprotection of 17β-estradiol on neurons and effects on expression of Brain Derived Neurotrophic Factor in cerebral cortex of rat after forebrain ischemia reperfusion. Methods 40 ovariectomized female SD rats were divided into four groups randomdy: saline + sham; 17β-estradiol + sham; 17β-estradiol + forebrain ischemia; saline + forebrain ischemia. Forebrain ischemia was induced by bilateral occlusion of the common caroid arteries for ten minutes combined with hypotension. The sham only uncovered the common arteries. Rats were treated with 17β-estradiol or saline by subabdnomimal injection for four weeks. 24 hours after forebrain ischemia or sham the rat was killed, brain was removed and paraffin-embedded. Sectioned for HE and BDNF stain, countering the number of necrosis and BDNF immunopositive neurons, T test and two-way classification ANOVA were used to analysis. Results 17β-estradiol could abviously reduce the number of necrosis neurons and increase the number of BDNF immunopositive neurons in cerebal cortex of rat ( not consider the effect of ischemia reperfusion,all p < 0.01 ). Conclusion 17β-estradiol can upregulate the expression of BDNF in cerebral cortex of rat after forebrain ischemia reperfusion, which may be one of the nueroprotection mechanism of 17β-estradiol.%目的 观察17β-雌二醇对前脑缺血-再灌注大鼠大脑皮层神经元保护作用及脑源性神经生长因子(BDNF)表达的影响.方法 双侧卵巢切除的雌性SD大鼠随机分为四组:生理盐水+假手术组;17β-雌二醇+假手术组;17β-雌二醇+短暂性前脑缺血模型组;生理盐水+短暂性前脑缺血模型组.以低血压联合双侧颈总动脉夹闭10min的方法造前脑缺血模型,只暴露双侧颈总动脉为假手术,17β-雌二醇为药物干预,生理盐水为安慰剂,腹腔注射应用4周.在造模术或假手术后24h处死大鼠,用HE染色检测大脑皮层坏死神经元数目,免疫组织化学染色

  19. Electroacupuncture effects on cortical neurons, as well as Janus kinase 2-signal transducer and activator of transcription 3 signal transduction pathway, in a rat model of cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Rong Liu; Nenggui Xu; Wei Yi; Kangbai Huang

    2012-01-01

    The present study established a model of focal cerebral ischemia through heat-coagulation induced occlusion of the middle cerebral artery. Following electroacupuncture at Baihui (GV20) and Dazhui (GV14), or intracerebroventricular infusion of AG490, a Janus kinase 2 phosphorylation inhibitor, the amount of necrotic or degenerated neurons in the ischemic cerebral cortex decreased, neuronal swelling was ameliorated, and expression of phosphorylated Janus kinase 2 and signal transducer and activator of transcription 3 decreased. Results confirmed that electroacupuncture promoted neuronal repair in the cerebral cortex by reducing expression of phosphorylated Janus kinase 2 and signal transducer and activator of transcription 3, as well as weakening the phosphorylated activation, thereby blocking abnormal activation of the Janus kinase 2- signal transducer and activator of transcription 3 signal transduction pathway.

  20. Pyramidal cells in prefrontal cortex: comparative observations reveal unparalleled specializations in neuronal structure among primate species.

    Directory of Open Access Journals (Sweden)

    Guy eElston

    2011-02-01

    Full Text Available The most ubiquitous neuron in the cerebral cortex, the pyramidal cell, is characterised by markedly different dendritic structure among different cortical areas. The complex pyramidal cell phenotype in granular prefrontal cortex (gPFC of higher primates endows specific biophysical properties and patterns of connectivity, which differ to those in other cortical regions. However, within the gPFC, data have been sampled from only a select few cortical areas. The gPFC of species such as human and macaque monkey includes more than 10 cortical areas. It remains unknown as to what degree pyramidal cell structure may vary among these cortical areas. Here we undertook a survey of pyramidal cells in the dorsolateral, medial and orbital gPFC of cercopethicid primates. We found marked heterogeneity in pyramidal cell structure within and between these regions. Moreover, trends for gradients in neuronal complexity varied among species. As neuron structure determines it’s computational abilities and memory storage capacity and connectivity, we propose that these specializations in the pyramidal cell phenotype are an important determinant of species specific executive cortical functions in primates.

  1. Chronic cerebral hypoperfusion induces vascular plasticity and hemodynamics but also neuronal degeneration and cognitive impairment

    Science.gov (United States)

    Jing, Zhen; Shi, Changzheng; Zhu, Lihui; Xiang, Yonghui; Chen, Peihao; Xiong, Zhilin; Li, Wenxian; Ruan, Yiwen; Huang, Li'an

    2015-01-01

    Chronic cerebral hypoperfusion (CCH) induces cognitive impairment, but the compensative mechanism of cerebral blood flow (CBF) is not fully understood. The present study mainly investigated dynamic changes in CBF, angiogenesis, and cellular pathology in the cortex, the striatum, and the cerebellum, and also studied cognitive impairment of rats induced by bilateral common carotid artery occlusion (BCCAO). Magnetic resonance imaging (MRI) techniques, immunochemistry, and Morris water maze were employed to the study. The CBF of the cortex, striatum, and cerebellum dramatically decreased after right common carotid artery occlusion (RCCAO), and remained lower level at 2 weeks after BCCAO. It returned to the sham level from 3 to 6 weeks companied by the dilation of vertebral arteries after BCCAO. The number of microvessels declined at 2, 3, and 4 weeks but increased at 6 weeks after BCCAO. Neuronal degeneration occurred in the cortex and striatum from 2 to 6 weeks, but the number of glial cells dramatically increased at 4 weeks after BCCAO. Cognitive impairment of ischemic rats was directly related to ischemic duration. Our results suggest that CCH induces a compensative mechanism attempting to maintain optimal CBF to the brain. However, this limited compensation cannot prevent neuronal loss and cognitive impairment after permanent ischemia. PMID:25853908

  2. Development of the human cerebral cortex: a histochemical study.

    Science.gov (United States)

    Tiu, Sau Cheung; Yew, David T; Chan, Wood Yee

    2003-01-01

    In recent years, improvement in diagnostic techniques has led to better recognition of "disorders of cortical development". These disorders constitute a significant cause of epilepsy, mental retardation, developmental delay and neurological deficits in childhood, and may also contribute to the pathogenesis of psychological and neurodegenerative diseases in adults. Hitherto, however, few systematic studies of the human fetal cortex have been performed, and little is known about the ontogenetic processes of the neocortex in man. The aim of the study is to establish an understanding of the developmental events that occur in the second and third trimesters of gestation, by investigating the biochemical patterns of development of the human neocortex during this period. The temporal and spatial patterns of expression of the neuronal markers gamma-aminobutyric acid (GABA), choline acetyltransferase (ChAT), dopamine beta hydroxylase (DBH), dopamine receptor DR1 and synaptophysin, as well as the glial cell markers glial fibrillary acidic protein (GFAP), S100B and excitatory amino acid transporter protein GLT-1 are delineated in the fetal cortex using immunohistochemistry. Results of this study showed that different neuronal and glial cell proteins follow different developmental patterns and many show inter- or intra-regional variations in expression. Details of these patterns are described and discussed. The early expression of these proteins suggests that they play important roles in the developmental processes of cell proliferation, migration and differentiation. Both neurotransmitters and glial cell proteins probably function outside the confines of synapses in the fetal brain, as paracrine/autocrine factors. Early developmental events seem to be dictated by an innate programme, whereas late events may be more susceptible to extrinsic influences. It is hoped that knowledge of the normal developmental process can lead to better understanding of the causes and mechanisms

  3. Sonic hedgehog signaling regulates mode of cell division of early cerebral cortex progenitors and increases astrogliogenesis

    Directory of Open Access Journals (Sweden)

    Geissy LL Araújo

    2014-03-01

    Full Text Available The morphogen Sonic Hedgehog (SHH plays a critical role in the development of different tissues. In the central nervous system, SHH is well known to contribute to the patterning of the spinal cord and separation of the brain hemispheres. In addition, it has recently been shown that SHH signaling also contributes to the patterning of the telencephalon and establishment of adult neurogenic niches. In this work, we investigated whether SHH signaling influences the behavior of neural progenitors isolated from the dorsal telencephalon, which generate excitatory neurons and macroglial cells in vitro. We observed that SHH increases proliferation of cortical progenitors and generation of astrocytes, whereas blocking SHH signaling with cyclopamine has opposite effects. In both cases, generation of neurons did not seem to be affected. However, cell survival was broadly affected by blockade of SHH signaling. SHH effects were related to three different cell phenomena: mode of cell division, cell cycle length and cell growth. Together, our data in vitro demonstrate that SHH signaling controls cell behaviors that are important for proliferation of cerebral cortex progenitors, as well as differentiation and survival of neurons and astroglial cells.

  4. Spiny Neurons of Amygdala, Striatum and Cortex Use Dendritic Plateau Potentials to Detect Network UP States

    Directory of Open Access Journals (Sweden)

    Katerina D Oikonomou

    2014-09-01

    Full Text Available Spiny neurons of amygdala, striatum, and cerebral cortex share four interesting features: [1] they are the most abundant cell type within their respective brain area, [2] covered by thousands of thorny protrusions (dendritic spines, [3] possess high levels of dendritic NMDA conductances, and [4] experience sustained somatic depolarizations in vivo and in vitro (UP states. In all spiny neurons of the forebrain, adequate glutamatergic inputs generate dendritic plateau potentials (dendritic UP states characterized by (i fast rise, (ii plateau phase lasting several hundred milliseconds and (iii abrupt decline at the end of the plateau phase. The dendritic plateau potential propagates towards the cell body decrementally to induce a long-lasting (longer than 100 ms, most often 200 – 800 ms steady depolarization (~20 mV amplitude, which resembles a neuronal UP state. Based on voltage-sensitive dye imaging, the plateau depolarization in the soma is precisely time-locked to the regenerative plateau potential taking place in the dendrite. The somatic plateau rises after the onset of the dendritic voltage transient and collapses with the breakdown of the dendritic plateau depolarization. We hypothesize that neuronal UP states in vivo reflect the occurrence of dendritic plateau potentials (dendritic UP states. We propose that the somatic voltage waveform during a neuronal UP state is determined by dendritic plateau potentials. A mammalian spiny neuron uses dendritic plateau potentials to detect and transform coherent network activity into a ubiquitous neuronal UP state. The biophysical properties of dendritic plateau potentials allow neurons to quickly attune to the ongoing network activity, as well as secure the stable amplitudes of successive UP states.

  5. Golgi Analysis of Neuron Morphology in the Presumptive Somatosensory Cortex and Visual Cortex of the Florida Manatee (Trichechus manatus latirostris).

    Science.gov (United States)

    Reyes, Laura D; Harland, Tessa; Reep, Roger L; Sherwood, Chet C; Jacobs, Bob

    2016-01-01

    The current study investigates neuron morphology in presumptive primary somatosensory (S1) and primary visual (V1) cortices of the Florida manatee (Trichechus manatus latirostris) as revealed by Golgi impregnation. Sirenians, including manatees, have an aquatic lifestyle, a large body size, and a relatively large lissencephalic brain. The present study examines neuron morphology in 3 cortical areas: in S1, dorsolateral cortex area 1 (DL1) and cluster cortex area 2 (CL2) and in V1, dorsolateral cortex area 4 (DL4). Neurons exhibited a variety of morphological types, with pyramidal neurons being the most common. The large variety of neuron types present in the manatee cortex was comparable to that seen in other eutherian mammals, except for rodents and primates, where pyramid-shaped neurons predominate. A comparison between pyramidal neurons in S1 and V1 indicated relatively greater dendritic branching in S1. Across all 3 areas, the dendritic arborization pattern of pyramidal neurons was also similar to that observed previously in the afrotherian rock hyrax, cetartiodactyls, opossums, and echidnas but did not resemble the widely bifurcated dendrites seen in the large-brained African elephant. Despite adaptations for an aquatic environment, manatees did not share specific neuron types such as tritufted and star-like neurons that have been found in cetaceans. Manatees exhibit an evolutionarily primitive pattern of cortical neuron morphology shared with most other mammals and do not appear to have neuronal specializations for an aquatic niche.

  6. Golgi Analysis of Neuron Morphology in the Presumptive Somatosensory Cortex and Visual Cortex of the Florida Manatee (Trichechus manatus latirostris).

    Science.gov (United States)

    Reyes, Laura D; Harland, Tessa; Reep, Roger L; Sherwood, Chet C; Jacobs, Bob

    2016-01-01

    The current study investigates neuron morphology in presumptive primary somatosensory (S1) and primary visual (V1) cortices of the Florida manatee (Trichechus manatus latirostris) as revealed by Golgi impregnation. Sirenians, including manatees, have an aquatic lifestyle, a large body size, and a relatively large lissencephalic brain. The present study examines neuron morphology in 3 cortical areas: in S1, dorsolateral cortex area 1 (DL1) and cluster cortex area 2 (CL2) and in V1, dorsolateral cortex area 4 (DL4). Neurons exhibited a variety of morphological types, with pyramidal neurons being the most common. The large variety of neuron types present in the manatee cortex was comparable to that seen in other eutherian mammals, except for rodents and primates, where pyramid-shaped neurons predominate. A comparison between pyramidal neurons in S1 and V1 indicated relatively greater dendritic branching in S1. Across all 3 areas, the dendritic arborization pattern of pyramidal neurons was also similar to that observed previously in the afrotherian rock hyrax, cetartiodactyls, opossums, and echidnas but did not resemble the widely bifurcated dendrites seen in the large-brained African elephant. Despite adaptations for an aquatic environment, manatees did not share specific neuron types such as tritufted and star-like neurons that have been found in cetaceans. Manatees exhibit an evolutionarily primitive pattern of cortical neuron morphology shared with most other mammals and do not appear to have neuronal specializations for an aquatic niche. PMID:27166161

  7. Peroxisome proliferator-activated receptor-γ agonist 15d-prostaglandin J2 mediates neuronal autophagy after cerebral ischemia-reperfusion injury.

    Directory of Open Access Journals (Sweden)

    Feng Xu

    Full Text Available Peroxisome proliferator-activated receptor-γ (PPAR-γ has recently emerged as potential therapeutic agents for cerebral ischemia-reperfusion (I/R injury because of anti-neuronal apoptotic actions. However, whether PPAR-γ activation mediates neuronal autophagy in such conditions remains unclear. Therefore, in this study, we investigated the role of PPAR-γ agonist 15-PGJ(2 on neuronal autophagy induced by I/R. The expression of autophagic-related protein in ischemic cortex such as LC3-II, Beclin 1, cathepsin-B and LAMP1 increased significantly after cerebral I/R injury. Furthermore, increased punctate LC3 labeling and cathepsin-B staining occurred in neurons. Treatment with PPAR-γ agonist 15d-PGJ(2 decreased not only autophagic-related protein expression in ischemic cortex, but also immunoreactivity of LC3 and cathepsin-B in neurons. Autophagic inhibitor 3-methyladenine (3-MA decreased LC3-II levels, reduced the infarct volume, and mimicked some protective effect of 15d-PGJ(2 against cerebral I/R injury. These results indicate that PPAR-γ agonist 15d-PGJ(2 exerts neuroprotection by inhibiting neuronal autophagy after cerebral I/R injury. Although the molecular mechanisms underlying PPAR-γ agonist in mediating neuronal autophagy remain to be determined, neuronal autophagy may be a new target for PPAR-γ agonist treatment in cerebral I/R injury.

  8. Chandelier and interfascicular neurons in the adult mouse piriform cortex

    Directory of Open Access Journals (Sweden)

    Jorge A Larriva-Sahd

    2010-12-01

    Full Text Available The structure of two neuron types native to the adult mouse piriform cortex (PC is described. The first cell, termed an interfascicular neuron (IFN, lies between the axon fascicles of layer I. The IFN axon divides dichotomously and daughter fibrils run horizontally in the domain of layer Ia. The frequent apposition of the IFN axon to distal denrites of the underlying pyramidal cells suggests an en passage synaptic interaction with them. A second neuron observed in layer II, or less frequently in layer III, matched in most respects the structure of the chandelier cell described elsewhere in the neo- and archi-cortex. In the PC, chandelier cells (PC-CC display the following peculiarities. First, the PC-CC axonal field distributes in the neuropil of layers II and III and candlesticks are in close apposition to the initial axonal segment of the pyramidal cell, although somatic interactions cannot be rule out. Second, the PC-CC ascending dendrites pierce layer I, receiving short collaterals and boutons en passage from the olfactory axons therein. The possible role of IFN´s and PC-CC and their interactions with the adjacent cells is discussed in the broad context of the cellular organization of the PC.

  9. Receptive field plasticity of neurons in rat auditory cortex

    Institute of Scientific and Technical Information of China (English)

    YANG Wenwei; GAO Lixia; SUN Xinde

    2004-01-01

    Using conventional electrophysiological technique, we investigated the plasticity of the frequency receptive fields (RF) of auditory cortex (AC) neurons in rats. In the AC, when the frequency difference between conditioning stimulus frequency (CSF) and the best frequency (BF) was in the range of 1-4 kHz, the frequency RF of AC neurons shifted. The smaller the differences between CSF and BF, the higher the probability of the RF shift and the greater the degree of the RF shift. To some extent, the plasticity of RF was dependent on the duration of the session of conditioning stimulus (CS). When the frequency difference between CSF and BF was bigger, the duration of the CS session needed to induce the plasticity was longer. The recovery time course of the frequency RF showed opposite changes after CS cessation.The RF shift could be induced by the frequency that was either higher or lower than the control BF, demonstrating no clear directional preference. The frequency RF of some neurons showed bidirectional shift, and the RF of other neurons showed single directional shift. The results suggest that the frequency RF plasticity of AC neurons could be considered as an ideal model for studying plasticity mechanism. The present study also provides important evidence for further study of learning and memory in auditory system.

  10. Htr2a gene and 5-HT2A receptor expression in the cerebral cortex studied using genetically modified mice

    Directory of Open Access Journals (Sweden)

    Rodrigo Andrade

    2010-08-01

    Full Text Available Serotonin receptors of the 5-HT2A subtype are robustly expressed in the cerebral cortex where they have been implicated in the pathophysiology and therapeutics of mental disorders and the actions of hallucinogens. Much less is known, however, about the specific cell types expressing 5-HT2A receptors in cortex. In the current study we use immunohistochemical and electrophysiological approaches in genetically modified mice to address the expression of the Htr2a gene and 5-HT2A receptors in cortex. We first use an EGFP expressing BAC transgenic mice and identify three main Htr2A gene expressing neuronal populations in cortex. The largest of these cell populations corresponds to layer V pyramidal cells of the anterior cortex, followed by GABAergic interneurons of the middle layers, and nonpyramidal cells of the subplate/Layer VIb. We then use 5-HT2A receptor knockout mice to identify an antibody capable of localizing 5-HT2A receptors in brain and use it to map these receptors. We find strong laminar expression of 5-HT2A receptors in cortex, especially along a diffuse band overlaying layer Va. This band exhibits a strong anteroposterior gradient that closely matches the localization of Htr2A expressing pyramidal cells of layer V. Finally we use electrophysiological and immunohistochemical approaches to show that most, but not all, GABAergic interneurons of the middle layers are parvalbumin expressing Fast-spiking interneurons and that these cells are depolarized and excited by serotonin, most likely through the activation of 5-HT2A receptors. These results clarify and extend our understanding of the cellular distribution of 5-HT2A receptors in the cerebral cortex.

  11. Surface Reconstruction and Optimization of Cerebral Cortex for Application Use.

    Science.gov (United States)

    Shin, Dong Sun; Park, Sang Kyu

    2016-03-01

    For the purposes of virtual surgery, medical education, medical communication, and realistic surface models of anatomic structures are required. In the most involved method, surface models can be made using segmentation and three-dimensional reconstruction procedures. Such models, however, are computationally expensive, and can be difficult to use. Therefore, optimization is often performed manually, but this is a time-consuming job that requires considerable artistic talent. In this article, the authors describe a method that uses Maya and ZBrush to construct optimized surface models of anatomic structures. The authors take 235 anatomic images generated from a cadaver, and perform segmentation and surface reconstruction using Photoshop and Mimics. Reconstructed surface models of the cerebral cortex are then optimized and divided by a morphing technique in Maya and ZBrush for use in medical applications. The optimized surface models do not require significant storage space, and are easily manufactured and modified. The resulting surface models can be displayed off-line and on-line in real time, as well as on smart phones. Using commercial software with the specialized functions described in this study, it is expected that the efficiencies produced by the proposed method will enable researchers to conveniently create surface models from serially sectioned images such as computed tomographs and magnetic resonance images. The surface models created in this research will also have widespread applications in both medical education and communication. PMID:26854785

  12. Laser speckle contrast reveals cerebral blood flow dynamics evoked by optogenetically controlled neuronal activity

    Science.gov (United States)

    Li, Nan; Thakor, Nitish V.; Pelled, Galit

    2013-03-01

    As a critical basis of functional brain imaging, neurovascular coupling describes the link between neuronal and hemodynamic changes. The majority of in vivo neurovascular coupling studies was performed by inducing sensory stimulation via afferent inputs. Unfortunately such an approach results in recruiting of multiple types of cells, which confounds the explanation of neuronal roles in stimulus evoked hemodynamic changes. Recently optogenetics has emerged to provide immediate control of neurons by exciting or inhibiting genetically engineered neurons expressing light sensitive proteins. However, there is a need for optical methods capable of imaging the concurrent hemodynamic changes. We utilize laser speckle contrast imaging (LSCI) to obtain high resolution display of cerebral blood flow (CBF) in the vicinity of the targeted neural population. LSCI is a minimally invasive method for imaging CBF in microvessels through thinned skull, and produces images with high spatiotemporal resolution, wide field of view. In the integrated system light sources with different wavelengths and band-passing/blocking filters were used to allow simultaneous optical manipulation of neuronal activities and optical imaging of corresponding CBF. Experimental studies were carried out in a rodent model expressing channalrhodopsin (ChR2) in excitatory neurons in the somatosensory cortex (S1). The results demonstrated significant increases of CBF in response to ChR2 stimulation (exciting neuronal firing) comparable to the CBF response to contralateral forepaw stimulation. The approach promises to be an exciting minimally invasive method to study neurovascular coupling. The complete system provides a novel approach for broad neuroscience applications.

  13. Protective effect and its mechanism of curcumin on ischemia-reperfusion injury of cerebral cortex in rats

    Directory of Open Access Journals (Sweden)

    Li LIU

    2013-03-01

    Full Text Available Objective  To investigate the effect of curcumin pretreatment on the expression of uncoupling protein 2 (UCP2 and mitochondrial transcription factor A (MTFA in rats' cerebral cortex against focal ischemia reperfusion injury. Methods  Eighty male SD rats weighed 220g–300g were randomly divided into 4 groups: sham-operated group, ischemia/reperfusion (I/R group, curcumine 50mg/kg+I/R (low dose group, and curcumine 100mg/kg+I/R (high dose group. The common carotid artery, external carotid artery and internal carotid artery on the right side were exposed in the sham-operated group. Animals of the other groups were subjected to a 2-hour period of right middle cerebral artery occlusion, followed by 24 hours of reperfusion, and then they were sacrificed. Curcumin was administered (ip in a dose of 50mg/kg (low dose group or 100mg/kg (high dose group for 5 days, respectively, prior to arterial occlusion. The pathological changes in neurons and their mitochondria in the cerebral cortex supplied by middle cerebral artery were observed with Nissl staining and electron microscope, respectively. The expressions of UCP2 and MTFA in corresponding cotex were assessed by immunohistochemistry and RT-PCR. Results  Compared with sham-operated group, animals in I/R group presented edema of neurons in the corresponding cortex, reduction in the number of Nissl bodies, and swelling of mitochondria with broken, even lysis of cristae. Low dose and high dose of curcumin pretreatment before brain ischemia significantly alleviated the loss of neurons and the damage of mitochondria, accompanied with an increase in the expression of UCP2 and TFAM (P<0.05, and the changes appeared a dose-dependent manner (P<0.05. Conclusions  Curcumin may prevent neurons from focal cerebral ischemia reperfusion injury by up-regulating UCP2 and MTFA. Regulation of mitochondrial biogenesis may probably be a potential target of curcumin as a neuroprotective drug.

  14. Lettuce glycoside B ameliorates cerebral ischemia reperfusion injury by increasing nerve growth factor and neurotrophin-3 expression of cerebral cortex in rats

    Directory of Open Access Journals (Sweden)

    Heqin Zhan

    2014-01-01

    Full Text Available Aims: The aim of the study was to investigate the effects of LGB on cerebral ischemia-reperfusion (I/R injury in rats and the mechanisms of action of LGB. Materials and Methods: The study involved extracting LGB from P. laciniata, exploring affects of LGB on brain ischemia and action mechanism at the molecular level. The cerebral ischemia reperfusion injury of middle cerebral artery occlusion was established. We measured brain histopathology and brain infarct rate to evaluate the effects of LGB on brain ischemia injury. The expressions of nerve growth factor (NGF and neurotrophin-3 (NT-3 were also measured to investigate the mechanisms of action by the real-time polymerase chain reaction and immunohistochemistry. Statistical analysis: All results were mentioned as mean ± standard deviation. One-way analysis of variance was used to determine statistically significant differences among the groups. Values of P < 0.05 were considered to be statistically significant. Results: Intraperitoneal injection of LGB at the dose of 12, 24, and 48 mg/kg after brain ischemia injury remarkably ameliorated the morphology of neurons and brain infarct rate (P < 0.05 , P < 0.01. LGB significantly increased NGF and NT-3 mRNA (messenger RNA and both protein expression in cerebral cortex at the 24 and 72 h after drug administration (P < 0.05, P < 0.01. Conclusions: LGB has a neuroprotective effect in cerebral I/R injury and this effect might be attributed to its upregulation of NGF and NT-3 expression ability in the brain cortex during the latter phase of brain ischemia.

  15. Proteomic analysis of rat cerebral cortex following subchronic acrolein toxicity

    International Nuclear Information System (INIS)

    Acrolein, a member of reactive α,β-unsaturated aldehydes, is a major environmental pollutant. Acrolein is also produced endogenously as a toxic by-product of lipid peroxidation. Because of high reactivity, acrolein may mediate oxidative damages to cells and tissues. It has been shown to be involved in a wide variety of pathological states including pulmonary, atherosclerosis and neurodegenerative diseases. In this study we employed proteomics approach to investigate the effects of subchronic oral exposures to 3 mg/kg of acrolein on protein expression profile in the brain of rats. Moreover effects of acrolein on malondialdehyde (MDA) levels and reduced glutathione (GSH) content were investigated. Our results revealed that treatment with acrolein changed levels of several proteins in diverse physiological process including energy metabolism, cell communication and transport, response to stimulus and metabolic process. Interestingly, several differentially over-expressed proteins, including β-synuclein, enolase and calcineurin, are known to be associated with human neurodegenerative diseases. Changes in the levels of some proteins were confirmed by Western blot. Moreover, acrolein increases the level of MDA, as a lipid peroxidation biomarker and decreased GSH concentrations, as a non-enzyme antioxidant in the brain of acrolein treated rats. These findings suggested that acrolein induces the oxidative stress and lipid peroxidation in the brain, and so that may contribute to the pathophysiology of neurological disorders. - Highlights: • Acrolein intoxication increased lipid peroxidation and deplete GSH in rat brain. • Effect of acrolein on protein levels of cerebral cortex was analyzed by 2DE-PAGE. • Levels of a number of proteins with different biological functions were increased

  16. Proteomic analysis of rat cerebral cortex following subchronic acrolein toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Rashedinia, Marzieh; Lari, Parisa [Department of Pharmacodynamics and Toxicology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad (Iran, Islamic Republic of); Abnous, Khalil, E-mail: Abnouskh@mums.ac.r [Pharmaceutical Research Center, Department of Medicinal Chemistry, Mashhad University of Medical Sciences, Mashhad (Iran, Islamic Republic of); Hosseinzadeh, Hossein, E-mail: Hosseinzadehh@mums.ac.ir [Pharmaceutical Research Center, Department of Pharmacodynamics and Toxicology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad (Iran, Islamic Republic of)

    2013-10-01

    Acrolein, a member of reactive α,β-unsaturated aldehydes, is a major environmental pollutant. Acrolein is also produced endogenously as a toxic by-product of lipid peroxidation. Because of high reactivity, acrolein may mediate oxidative damages to cells and tissues. It has been shown to be involved in a wide variety of pathological states including pulmonary, atherosclerosis and neurodegenerative diseases. In this study we employed proteomics approach to investigate the effects of subchronic oral exposures to 3 mg/kg of acrolein on protein expression profile in the brain of rats. Moreover effects of acrolein on malondialdehyde (MDA) levels and reduced glutathione (GSH) content were investigated. Our results revealed that treatment with acrolein changed levels of several proteins in diverse physiological process including energy metabolism, cell communication and transport, response to stimulus and metabolic process. Interestingly, several differentially over-expressed proteins, including β-synuclein, enolase and calcineurin, are known to be associated with human neurodegenerative diseases. Changes in the levels of some proteins were confirmed by Western blot. Moreover, acrolein increases the level of MDA, as a lipid peroxidation biomarker and decreased GSH concentrations, as a non-enzyme antioxidant in the brain of acrolein treated rats. These findings suggested that acrolein induces the oxidative stress and lipid peroxidation in the brain, and so that may contribute to the pathophysiology of neurological disorders. - Highlights: • Acrolein intoxication increased lipid peroxidation and deplete GSH in rat brain. • Effect of acrolein on protein levels of cerebral cortex was analyzed by 2DE-PAGE. • Levels of a number of proteins with different biological functions were increased.

  17. Lysine and arginine reduce the effects of cerebral ischemic insults and inhibit glutamate-induced neuronal activity in rats

    Directory of Open Access Journals (Sweden)

    Takashi Kondoh

    2010-06-01

    Full Text Available Intravenous administration of arginine was shown to be protective against cerebral ischemic insults via nitric oxide production and possibly via additional mechanisms. The present study aimed at evaluating the neuroprotective effects of oral administration of lysine (a basic amino acid, arginine, and their combination on ischemic insults (cerebral edema and infarction and hemispheric brain swelling induced by transient middle cerebral artery occlusion/reperfusion in rats. Magnetic resonance imaging and 2,3,5-triphenyltetrazolium chloride staining were performed two days after ischemia induction. In control animals, the major edematous areas were observed in the cerebral cortex and striatum. The volumes associated with cortical edema were significantly reduced by lysine (2.0 g/kg, arginine (0.6 g/kg, or their combined administration (0.6 g/kg each. Protective effects of these amino acids on infarction were comparable to the inhibitory effects on edema formation. Interestingly, these amino acids, even at low dose (0.6 g/kg, were effective to reduce hemispheric brain swelling. Additionally, the effects of in vivo microiontophoretic (juxtaneuronal applications of these amino acids on glutamate-evoked neuronal activity in the ventromedial hypothalamus were investigated in awake rats. Glutamate-induced neuronal activity was robustly inhibited by microiontophoretic applications of lysine or arginine onto neuronal membranes. Taken together, our results demonstrate the neuroprotective effects of oral ingestion of lysine and arginine against ischemic insults (cerebral edema and infarction, especially in the cerebral cortex, and suggest that suppression of glutamate-induced neuronal activity might be the primary mechanism associated with these neuroprotective effects.

  18. EFFECT OF ELECTROACUPUNCTURE ON NOREPINEPHRINE LEVEL AND APOPTOSIS IN CEREBRAL CORTEX TISSUE IN RATS WITH CEREBRAL ISCHEMIA-REPERFUSION

    Institute of Scientific and Technical Information of China (English)

    邹晓静; 施静; 刘敬; 李伶俐; 刘晓春

    2004-01-01

    Objective: To investigate the underlying neurobiological mechanism of the protective effect of electroacupuncture (EA) during cerebral ischemia-reperfusion (CI-R). Methods: In the first part of the study, 15 SD rats were evenly randomized into control group, CI-R-48h model group and CI-R-48h+EA group. The cortical apoptosis and expression of Bcl-2 and Bax proteins in each group were detected by flow cytometer (FCM). In the second part of the study, 75 SD rats were evenly randomized into control, CI-R-3min, CI-R-3min+EA, CI-R-48h and CI-R-48h+EA groups. Cortical norepinephrine (NE) concentration was detected by fluorescence spectrometer. CI-R model was established by occlusion of the bilateral common carotid arteries and reperfusion. EA (4~16 Hz, 1~3 V) was applied after reperfusion respectively. Results: In the first part of this study, results indicated that the number of the apoptotic neurons and the apoptosis rate of CI-R-48h group were significantly higher than those of control group; while comparison between CI-R-48h+EA and CI-R-48h groups showed that the number of the apoptotic neurons and the apoptosis rate of the former group were significantly lower than those of the later group (P<0.05). In comparison with control group, after CI-48h, Bax expression was up-regulated significantly and Bcl-2 down-regulated markedly (P<0.05). Comparison between CI-R-48h and CI-R-48h+EA group indicated that Bax expression of the later group was significantly lower than that of the former group, while Bcl-2 expression of CI-R-48h+EA group was significantly higher than that of CI-R-48h group (P<0.05), suggesting that EA could reverse CI induced reactions of these two indexes. In the second part of the study, in comparison with control group, NE concentration in cerebral cortex of CI-R-3min group increased significantly (P<0.05); while NE content of CI-R-3min+EA group was significantly lower than that of CI-R-3min group (P<0.05). No significant difference was found between

  19. Ultrastructural changes of rat cortical neurons following ligustrazine intervention for cerebral ischemia/reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    Hui Zhang; Jianfeng Dong; Qiuzhen Zhao; Wen Song; Aihua Bo

    2008-01-01

    BACKGROUND: Ligustrazine can reduce the production of free radicals and the content of malonaldehyde, and improve the enzymatic activity of adenosine-triphosphate in cerebral anoxia. It also can increase the expression of heat shock protein-70 and Bcl-2, thus alleviating brain tissue injury caused by cerebral ischemia/reperfusion. This study aimed to address the question of whether ligustrazine can protect the membrane structure of neurons.OBJECTIVE: To establish rat models of cerebral ischemia/reperfusion, observe the membrane structure and main organelles of neurons with electron microscope after ligustrazine intervention, and to analyze the dose-dependent effects of ligustrazine on neuronal changes.DESIGN: Arandomized controlled study.SETTING: Department of Anatomy Research and Electron Microscopy, Hebei North University. MATERIALS: Forty Wistar rats of SPS grade, weighing 180–250 g and equal proportion of female and male, were provided by Hebei Medical University Animal Center (No. 060126). The ligustrazine injection (40 g/L, No. 05012) was produced by Beijing Yongkang Yaoye. LKB4 Ultramicrotome was purchased from LKB Company in Sweden. JEM100CXII electron microscope was purchased from JEOL in Japan.METHODS: The experiment was performed in the Laboratory of the Department of Anatomy and Electron Microscopy, Hebei North University from June to August 2006. ① Wistar rats were allowed to adapt for 3 days, and were then randomly divided into four groups, according to the numeration table method: normal group, model group, low-dose ligustrazine group, and high-dose ligustrazine group. There were 10 rats in each group. ②Rats in the model group, low-dose ligustrazine group, and high-dose ligustrazine group un-derwent cerebral ischemia/reperfusion model, according to Bannister's method. The carotid artery was opened for reperfusion after 90 minutes of cerebral ischemia. Samples were collected from the cerebral cor-tex after 24 hours. Animals from the ligustrazine

  20. Spreading convulsions, spreading depolarization and epileptogenesis in human cerebral cortex.

    Science.gov (United States)

    Dreier, Jens P; Major, Sebastian; Pannek, Heinz-Wolfgang; Woitzik, Johannes; Scheel, Michael; Wiesenthal, Dirk; Martus, Peter; Winkler, Maren K L; Hartings, Jed A; Fabricius, Martin; Speckmann, Erwin-Josef; Gorji, Ali

    2012-01-01

    Spreading depolarization of cells in cerebral grey matter is characterized by massive ion translocation, neuronal swelling and large changes in direct current-coupled voltage recording. The near-complete sustained depolarization above the inactivation threshold for action potential generating channels initiates spreading depression of brain activity. In contrast, epileptic seizures show modest ion translocation and sustained depolarization below the inactivation threshold for action potential generating channels. Such modest sustained depolarization allows synchronous, highly frequent neuronal firing; ictal epileptic field potentials being its electrocorticographic and epileptic seizure its clinical correlate. Nevertheless, Leão in 1944 and Van Harreveld and Stamm in 1953 described in animals that silencing of brain activity induced by spreading depolarization changed during minimal electrical stimulations. Eventually, epileptic field potentials were recorded during the period that had originally seen spreading depression of activity. Such spreading convulsions are characterized by epileptic field potentials on the final shoulder of the large slow potential change of spreading depolarization. We here report on such spreading convulsions in monopolar subdural recordings in 2 of 25 consecutive aneurismal subarachnoid haemorrhage patients in vivo and neocortical slices from 12 patients with intractable temporal lobe epilepsy in vitro. The in vitro results suggest that γ-aminobutyric acid-mediated inhibition protects from spreading convulsions. Moreover, we describe arterial pulse artefacts mimicking epileptic field potentials in three patients with subarachnoid haemorrhage that ride on the slow potential peak. Twenty-one of the 25 subarachnoid haemorrhage patients (84%) had 656 spreading depolarizations in contrast to only three patients (12%) with 55 ictal epileptic events isolated from spreading depolarizations. Spreading depolarization frequency and depression

  1. Cellullar insights into cerebral cortical development: focusing on the locomotion mode of neuronal migration

    Directory of Open Access Journals (Sweden)

    Takeshi eKawauchi

    2015-10-01

    Full Text Available The mammalian brain consists of numerous compartments that are closely connected with each other via neural networks, comprising the basis of higher order brain functions. The highly specialized structure originates from simple pseudostratified neuroepithelium-derived neural progenitors located near the ventricle. A long journey by neurons from the ventricular side is essential for the formation of a sophisticated brain structure, including a mammalian-specific six-layered cerebral cortex. Neuronal migration consists of several contiguous steps, but the locomotion mode comprises a large part of the migration. The locomoting neurons exhibit unique features; a radial glial fiber-dependent migration requiring the endocytic recycling of N-cadherin and a neuron-specific migration mode with dilation/swelling formation that requires the actin and microtubule organization possibly regulated by cyclin-dependent kinase 5 (Cdk5, Dcx, p27kip1, Rac1 and POSH. Here I will introduce the roles of various cellular events, such as cytoskeletal organization, cell adhesion and membrane trafficking, in the regulation of the neuronal migration, with particular focus on the locomotion mode.

  2. Cerebral ischemia—induced neuronal apoptosis mediated by nitric oxide

    Institute of Scientific and Technical Information of China (English)

    NomuY

    2002-01-01

    To elucidate the cellular and molecular mechanism of cerebral ischemia-induced neuronal apoptosis mediated by nitric oxide (NO) in the brain,we investigated:(1)cell death in hippocampal CA1 neurons of rats after a rransient four vessel occlusion (4VO)/reperfusion and (2) apoptosis induced by NOC18(NO releaser) using SHSY5Y cells,a human neuroblastoma cell line.We found that 4VO caused expression of inducible type of NO synthase (iNOS) in glial cells and neuronal apoptosis in CA1 region of rats.Next we examined in vitro apoptotic effects of NOC18 on SHSY5Y cells and suggest that NO decrease mitochondrial membrane potential,release cytochrome C from mitochondria,activates caspase-3,degrade inhibitor of caspase-activated DNase(Icad),and activated DNase translocate into nucleus and induce DNA fragmentation.Thus we conclude that the excess amount of NO produced by glial iNOS at cerebral ischemia could be involved in neuronal apoptosis in CA1 region.Regarding NO action on neurons,we further obtained that NO propects neuronal apoptosis in PC12 cells perhaps by nitrosylation of caspase,subsequent reduction of proteolytic activity.Taken together,we suggest that NO seem to exert dual effects(toxic and beneficial) on neuronal apoptosis,the one (toxic);apoptosis-induction throuth the decrease in mitochondrial membrane potentials and cytochrome C release and the othe (beneficial);protection against apoptosis through the inhibition of caspase activity.

  3. Computational Image Analysis Reveals Intrinsic Multigenerational Differences between Anterior and Posterior Cerebral Cortex Neural Progenitor Cells

    Directory of Open Access Journals (Sweden)

    Mark R. Winter

    2015-10-01

    Full Text Available Time-lapse microscopy can capture patterns of development through multiple divisions for an entire clone of proliferating cells. Images are taken every few minutes over many days, generating data too vast to process completely by hand. Computational analysis of this data can benefit from occasional human guidance. Here we combine improved automated algorithms with minimized human validation to produce fully corrected segmentation, tracking, and lineaging results with dramatic reduction in effort. A web-based viewer provides access to data and results. The improved approach allows efficient analysis of large numbers of clones. Using this method, we studied populations of progenitor cells derived from the anterior and posterior embryonic mouse cerebral cortex, each growing in a standardized culture environment. Progenitors from the anterior cortex were smaller, less motile, and produced smaller clones compared to those from the posterior cortex, demonstrating cell-intrinsic differences that may contribute to the areal organization of the cerebral cortex.

  4. Linear coupling between cerebral blood flow and oxygen consumption in activated human cortex

    OpenAIRE

    Richard D. Hoge; Atkinson, Jeff; Gill, Brad; Crelier, Gérard R.; Marrett, Sean; Pike, G Bruce

    1999-01-01

    The aim of this study was to test the hypothesis that, within a specific cortical unit, fractional changes in cerebral blood flow (CBF) and cerebral metabolic rate of oxygen consumption (CMRO2) are coupled through an invariant relationship during physiological stimulation. This aim was achieved by simultaneously measuring relative changes in these quantities in human primary visual cortex (V1) during graded stimulation with patterns designed to selectively activate different populations of V1...

  5. THE EFFECT OF LIGUSTRAZINE ON NEUROGENESIS IN CORTEX AFTER FOCAL CEREBRAL ISCHEMIA IN RATS

    Institute of Scientific and Technical Information of China (English)

    Qiu Fen; Liu Yong; Zhang Pengbo; Kang Qianyan; Tian Yingfang; Chen Xinlin; Zhao Jianjun; Qi Cunfang

    2006-01-01

    Objective To explore the effect of Ligustrazine on neurogenesis in cortex after focal cerebral ischemia in rats. Methods Focal cerebral ischemia was induced by left middle cerebral arteryocclusion with asuture. Two hours later, injection of Ligustrazine (80 mg/kg, 1 time/d) was performed peritoneally. Four hours after the ischemia,5-bromodeoxyuridine (BrdU) (50 mg/kg, 1 time/d) was injected peritoneally. At 7 d, 14 d and 21 d after ischemia,BrdU positive cells in the cortex were observed by immunohistochemical staining. Results In ischemic model group, at 7 day, sparsely-distributed BrdU positive cells were observed in the Ⅱ - Ⅵ layers of the ipsilateral cortex, with a band-like distribution in ischemic penumbra. With the prolongation of ischemia, the number of BrdU positive cells increased.In Ligustrazine group, BrdU positive cells were also observed in the Ⅱ - Ⅵ layers of the cortex, with an intense distribution in ischemic penumbra. The numbers of BrdU positive cells at 7 d, 14 d and 21 d were more than those in ischemic model group respectively. Conclusion Ligustrazine increases the proliferated cells in cortex after focal cerebral ischemia in rats. The results suggest that it may be useful for promoting self-repair after ischemia.

  6. Motor, cognitive, and affective areas of the cerebral cortex influence the adrenal medulla.

    Science.gov (United States)

    Dum, Richard P; Levinthal, David J; Strick, Peter L

    2016-08-30

    Modern medicine has generally viewed the concept of "psychosomatic" disease with suspicion. This view arose partly because no neural networks were known for the mind, conceptually associated with the cerebral cortex, to influence autonomic and endocrine systems that control internal organs. Here, we used transneuronal transport of rabies virus to identify the areas of the primate cerebral cortex that communicate through multisynaptic connections with a major sympathetic effector, the adrenal medulla. We demonstrate that two broad networks in the cerebral cortex have access to the adrenal medulla. The larger network includes all of the cortical motor areas in the frontal lobe and portions of somatosensory cortex. A major component of this network originates from the supplementary motor area and the cingulate motor areas on the medial wall of the hemisphere. These cortical areas are involved in all aspects of skeletomotor control from response selection to motor preparation and movement execution. The second, smaller network originates in regions of medial prefrontal cortex, including a major contribution from pregenual and subgenual regions of anterior cingulate cortex. These cortical areas are involved in higher-order aspects of cognition and affect. These results indicate that specific multisynaptic circuits exist to link movement, cognition, and affect to the function of the adrenal medulla. This circuitry may mediate the effects of internal states like chronic stress and depression on organ function and, thus, provide a concrete neural substrate for some psychosomatic illness. PMID:27528671

  7. A comparison of the apoptotic effect of Delta(9)-tetrahydrocannabinol in the neonatal and adult rat cerebral cortex.

    Science.gov (United States)

    Downer, Eric J; Gowran, Aoife; Campbell, Veronica A

    2007-10-17

    The maternal use of cannabis during pregnancy results in a number of cognitive deficits in the offspring that persist into adulthood. The endocannabinoid system has a role to play in neurodevelopmental processes such as neurogenesis, migration and synaptogenesis. However, exposure to phytocannabinoids, such as Delta(9)-tetrahydrocannabinol, during gestation may interfere with these events to cause abnormal patterns of neuronal wiring and subsequent cognitive impairments. Aberrant cell death evoked by Delta(9)-tetrahydrocannabinol may also contribute to cognitive deficits and in cultured neurones Delta(9)-tetrahydrocannabinol induces apoptosis via the CB(1) cannabinoid receptor. In this study we report that Delta(9)-tetrahydrocannabinol (5-50 microM) activates the stress-activated protein kinase, c-jun N-terminal kinase, and the pro-apoptotic protease, caspase-3, in in vitro cerebral cortical slices obtained from the neonatal rat brain. The proclivity of Delta(9)-tetrahydrocannabinol to impact on these pro-apoptotic signalling molecules was not observed in in vitro cortical slices obtained from the adult rat brain. In vivo, subcutaneous administration of Delta(9)-tetrahydrocannabinol (1-30 mg/kg) activated c-jun N-terminal kinase, caspase-3 and cathepsin-D, and induced DNA fragmentation in the cerebral cortex of neonatal rats. In contrast, in vivo administration of Delta(9)-tetrahydrocannabinol to adult rats was not associated with the apoptotic pathway in the cerebral cortex. The data provide evidence which supports the hypothesis that the neonatal rat brain is more vulnerable to the neurotoxic influence of Delta(9)-tetrahydrocannabinol, suggesting that the cognitive deficits that are observed in humans exposed to marijuana during gestation may be due, in part, to abnormal engagement of the apoptotic cascade during brain development.

  8. Changes in synapse quantity and growth associated protein 43 expression in the motor cortex of focal cerebral ischemic rats following catalpol treatment

    Institute of Scientific and Technical Information of China (English)

    Dong Wan; Huifeng Zhu; Yong Luo; Peng Xie

    2011-01-01

    The present study investigated the effects of catalpol, the main constituent of the Chinese herb Rehmannia root, on neurons following brain ischemia. A rat model of focal permanent brain ischemia was established using electrocoagulation. The rats were intraperitoneally injected with catalpol, at a dose of 5 mg/kg, daily for 1 week. Results showed that the number of neuronal synapses in the motor cortex and growth associated protein 43 expression were increased following catalpol treatment, indicating that catalpol might contribute to neuroplasticity and ameliorate functional neurological deficits induced by cerebral ischemia.

  9. The effects of prefrontal cortex inactivation on object responses of single neurons in the inferotemporal cortex during visual search

    OpenAIRE

    Monosov, Ilya E.; David L Sheinberg; Thompson, Kirk G.

    2011-01-01

    Inferotemporal cortex (IT) is believed to be directly involved in object processing and necessary for accurate and efficient object recognition. The frontal eye field (FEF) is an area in the primate prefrontal cortex that is involved in visual spatial selection and is thought to guide spatial attention and eye movements. We show that object selective responses of IT neurons and behavioral performance are affected by changes in frontal eye field activity. This was found in monkeys performing a...

  10. Molecular pathways underlying projection neuron production and migration during cerebral cortical development

    Directory of Open Access Journals (Sweden)

    Chiaki eOhtaka-Maruyama

    2015-12-01

    Full Text Available Glutamatergic neurons of the mammalian cerebral cortex originate from the radial glia (RG progenitors in the ventricular zone (VZ. During corticogenesis, neuroblasts migrate toward the pial surface using two different migration modes. One is multipolar (MP migration with random directional movement, and the other is locomotion, which is a unidirectional movement guided by the RG fiber. After reaching their final destination, the neurons finalize their migration by terminal translocation, which is followed by maturation via dendrite extension to initiate synaptogenesis and thereby complete neural circuit formation. This switching of migration modes during cortical development is unique in mammals, which suggests that the RG-guided locomotion mode may contribute to the evolution of the mammalian neocortical 6-layer structure. Many factors have been reported to be involved in the regulation of this radial neuronal migration process. In general, the radial migration can be largely divided into four steps; (1 maintenance and departure from the VZ of neural progenitor cells, (2 MP migration and transition to bipolar cells, (3 RG-guided locomotion, and (4 terminal translocation and dendrite maturation. Among these, many different gene mutations or knockdown effects have resulted in failure of the MP to bipolar transition (step 2, suggesting that it is a critical step, particularly in radial migration. Moreover, this transition occurs at the subplate layer. In this review, we summarize recent advances in our understanding of the molecular mechanisms underlying each of these steps. Finally, we discuss the evolutionary aspects of neuronal migration in corticogenesis.

  11. Chemogenetic silencing of neurons in retrosplenial cortex disrupts sensory preconditioning.

    Science.gov (United States)

    Robinson, Siobhan; Todd, Travis P; Pasternak, Anna R; Luikart, Bryan W; Skelton, Patrick D; Urban, Daniel J; Bucci, David J

    2014-08-13

    An essential aspect of episodic memory is the formation of associations between neutral sensory cues in the environment. In light of recent evidence that this critical aspect of learning does not require the hippocampus, we tested the involvement of the retrosplenial cortex (RSC) in this process using a chemogenetic approach that allowed us to temporarily silence neurons along the entire rostrocaudal extent of the RSC. A viral vector containing the gene for a synthetic inhibitory G-protein-coupled receptor (hM4Di) was infused into RSC. When the receptor was later activated by systemic injection of clozapine-N-oxide, neural activity in RSC was transiently silenced (confirmed using a patch-clamp procedure). Rats expressing hM4Di and control rats were trained in a sensory preconditioning procedure in which a tone and light were paired on some trials and a white noise stimulus was presented alone on the other trials during the Preconditioning phase. Thus, rats were given the opportunity to form an association between a tone and a light in the absence of reinforcement. Later, the light was paired with food. During the test phase when the auditory cues were presented alone, controls exhibited more conditioned responding during presentation of the tone compared with the white noise reflecting the prior formation of a tone-light association. Silencing RSC neurons during the Preconditioning phase prevented the formation of an association between the tone and light and eliminated the sensory preconditioning effect. These findings indicate that RSC may contribute to episodic memory formation by linking essential sensory stimuli during learning.

  12. Upregulation of excitatory neurons and downregulation of inhibitory neurons in barrel cortex are associated with loss of whisker inputs

    Directory of Open Access Journals (Sweden)

    Zhang Guanjun

    2013-01-01

    Full Text Available Abstract Loss of a sensory input causes the hypersensitivity in other modalities. In addition to cross-modal plasticity, the sensory cortices without receiving inputs undergo the plastic changes. It is not clear how the different types of neurons and synapses in the sensory cortex coordinately change after input deficits in order to prevent loss of their functions and to be used for other modalities. We studied this subject in the barrel cortices from whiskers-trimmed mice vs. controls. After whisker trimming for a week, the intrinsic properties of pyramidal neurons and the transmission of excitatory synapses were upregulated in the barrel cortex, but inhibitory neurons and GABAergic synapses were downregulated. The morphological analyses indicated that the number of processes and spines in pyramidal neurons increased, whereas the processes of GABAergic neurons decreased in the barrel cortex. The upregulation of excitatory neurons and the downregulation of inhibitory neurons boost the activity of network neurons in the barrel cortex to be high levels, which prevent the loss of their functions and enhances their sensitivity to sensory inputs. These changes may prepare for attracting the innervations from sensory cortices and/or peripheral nerves for other modalities during cross-modal plasticity.

  13. Characterization of primary and secondary cultures of astrocytes prepared from mouse cerebral cortex

    DEFF Research Database (Denmark)

    Skytt, Dorte Marie; Madsen, Karsten Kirkegaard; Pajecka, Kamilla;

    2010-01-01

    Astrocyte cultures were prepared from cerebral cortex of new-born and 7-day-old mice and additionally, the cultures from new-born animals were passaged as secondary cultures. The cultures were characterized by immunostaining for the astrocyte markers glutamine synthetase (GS), glial fibrillary...

  14. Reorganization of neuronal circuits in growing visual cortex

    Science.gov (United States)

    Keil, Wolfgang; Loewel, Siegrid; Wolf, Fred; Kaschube, Matthias

    2009-03-01

    The dynamics of reorganization of large cortical circuits is rooted in plasticity of individual synapses, but rules governing the collective behavior of large networks of neurons are only poorly understood. The postnatal brain growth partly evoked by extensive formation of new synaptic connections may expose cortical areas to a 'natural perturbation' sufficiently strong to observe signatures of large scale reorganization. Quantifying large sets of imaging data from juvenile cat visual cortex, we observe a novel mode of reorganization of domains that prefer inputs from one eye or the other. Our theoretical analysis shows that this mode can be explained quantitatively by the so called Zigzag instability, a dynamical reorganization, well-known in the field of pattern formation in physics, by which 2D isotropic Turing patterns respond to an increase in their typical spatial scale with a zigzag-like bending of domains. We point out that this instability has in fact been predicted, albeit implicitly, by most models of visual cortical development that have been proposed so far. We conclude that cortical networks can undergo large scale reorganizations during normal postnatal development.

  15. An automated pipeline for cortical surface generation and registration of the cerebral cortex

    Science.gov (United States)

    Li, Wen; Ibanez, Luis; Gelas, Arnaud; Yeo, B. T. Thomas; Niethammer, Marc; Andreasen, Nancy C.; Magnotta, Vincent A.

    2011-03-01

    The human cerebral cortex is one of the most complicated structures in the body. It has a highly convoluted structure with much of the cortical sheet buried in sulci. Based on cytoarchitectural and functional imaging studies, it is possible to segment the cerebral cortex into several subregions. While it is only possible to differentiate the true anatomical subregions based on cytoarchitecture, the surface morphometry aligns closely with the underlying cytoarchitecture and provides features that allow the surface of the cortex to be parcellated based on the sulcal and gyral patterns that are readily visible on the MR images. We have developed a fully automated pipeline for the generation and registration of cortical surfaces in the spherical domain. The pipeline initiates with the BRAINS AutoWorkup pipeline. Subsequently, topology correction and surface generation is performed to generate a genus zero surface and mapped to a sphere. Several surface features are then calculated to drive the registration between the atlas surface and other datasets. A spherical diffeomorphic demons algorithm is used to co-register an atlas surface onto a subject surface. A lobar based atlas of the cerebral cortex was created from a manual parcellation of the cortex. The atlas surface was then co-registered to five additional subjects using a spherical diffeomorphic demons algorithm. The labels from the atlas surface were warped on the subject surface and compared to the manual raters. The average Dice overlap index was 0.89 across all regions.

  16. Response Selectivity Is Correlated to Dendritic Structure in Parvalbumin-Expressing Inhibitory Neurons in Visual Cortex

    OpenAIRE

    Runyan, Caroline A.; Sur, Mriganka

    2013-01-01

    Inhibitory neurons have been shown to perform a variety of functions within brain circuits, including shaping response functions in target cells. Still, how the properties of specific inhibitory neuron classes relate to their local circuits remains unclear. To better understand the distribution and origins of orientation selectivity in inhibitory neurons expressing the calcium binding protein parvalbumin (PV) in the mouse primary visual cortex, we labeled PV+ neurons with red fluorescent prot...

  17. Effects of Dimethyl Sulfoxide on Neuronal Response Characteristics in Deep Layers of Rat Barrel Cortex

    Science.gov (United States)

    Soltani, Narjes; Mohammadi, Elham; Allahtavakoli, Mohammad; Shamsizadeh, Ali; Roohbakhsh, Ali; Haghparast, Abbas

    2016-01-01

    Introduction: Dimethyl sulfoxide (DMSO) is a chemical often used as a solvent for water-insoluble drugs. In this study, we evaluated the effect of intracerebroventricular (ICV) administration of DMSO on neural response characteristics (in 1200–1500 μm depth) of the rat barrel cortex. Methods: DMSO solution was prepared in 10% v/v concentration and injected into the lateral ventricle of rats. Neuronal spontaneous activity and neuronal responses to deflection of the principal whisker (PW) and adjacent whisker (AW) were recorded in barrel cortex. A condition test ratio (CTR) was used to measure inhibitory receptive fields in barrel cortex. Results: The results showed that both PW and AW evoked ON and OFF responses, neuronal spontaneous activity and inhibitory receptive fields did not change following ICV administration of DMSO. Conclusion: Results of this study suggest that acute ICV administration of 10% DMSO did not modulate the electrophysiological characteristics of neurons in the l deep ayers of rat barrel cortex.

  18. In Utero Electroporation: Assay System for Migration of Cerebral Cortical Neurons

    Science.gov (United States)

    Tabata, Hidenori; Nakajima, Kazunori

    During the development of the cerebral cortex, the majority of cortical neurons are generated in the ventricular zone (VZ) facing the lateral ventricle and then migrate toward the pial surface to form the highly organized 6-layered cerebral cortex. Detailed profiles of these processes and their molecular mechanisms had been largely unknown because of the absence of an efficient assay system. The in vivo electroporation system was initially devised for use within chick embryos (Funahashi et al., 1999; Itasaki et al., 1999; Momose et al., 1999; Muramatsu et al., 1997), and we and other groups have used that system as a basis for developing an in utero electroporation system, which allows plasmid DNA to be introduced into cortical progenitor cells in developing mouse embryos in the uterus (Fukuchi-Shimogori and Grove, 2001; Saito and Nakatsuji, 2001; Tabata and Nakajima, 2001; Takahashi et al., 2002). In utero electroporation of other sites in the brain, including the hippocampus (Navarro-Quiroga et al., 2007), cerebral basal ganglia (Borrell et al., 2005; Nakahira et al., 2006), cortical hem (Takiguchi-Hayashi et al., 2004), and dorsal thalamus (Bonnin et al., 2007), has recently been reported. Introducing green fluorescent protein (GFP) enables the entire processes of migration and layer formation to be visualized (Ajioka and Nakajima, 2005; Sasaki et al., 2008; Tabata and Nakajima, 2002, 2003), and the role of any gene involved in these processes can be easily assessed by overexpressing the proteins or their mutants (Ohshima et al., 2007), or by knocking down the genes by the RNA interference technique (Bai et al., 2003). Furthermore, the Tet-On/Off system and/or other plasmid- vector-based technologies will expand the potential of the analyses. In this section we review the principles and methods of gene transfer into the cortical wall of mouse embryos by means of the in utero electroporation system.

  19. Centrophenoxine improves chronic cerebral ischemia induced cognitive deficit and neuronal degeneration in rats

    Institute of Scientific and Technical Information of China (English)

    Yun LIAO; Rui WANG; Xi-can TANG

    2004-01-01

    AIM: To study the effects of centrophenoxine (CPH, meclofenoxate) on chronic cerebral hypoperfusion induced deficits in rats. METHODS: Chronic hypoperfusion in rats was performed by permanent bilateral ligation of the common carotid arteries. Morris water maze was used to measure spatial memory performance. Spectrophotometrical techniques were used to assay SOD, GPx activities, MDA content, TXB2, and 6-keto-PGF1α levels. Morphological change was examined by HE staining. The expression of Bax and p53 protein were assayed by immunohistochemistry analysis. RESULTS: Chronic hypoperfusion in rats resulted in spatial memory impairments shown by longer escape latency and shorter time spent in the target quadrant. These behavioral dysfunction were accompanied by increase in SOD and GPx activities, the content of MDA, the levels of pro-inflammatory mediators (TXB2, 6-keto-PGF1α), overexpression of Bax and P53 protein, and delayed degeneration of neurons in cortex and hippocampus. Oral administration of CPH (100 mg/kg, once per day for 37 d) markedly improved the memory impairment, reduced the increase in antioxidant enzyme activities, MDA content and the levels of pro-inflammatory mediators to their normal levels, and attenuated neuronal damage. CONCLUSION: The abilities of CPH to attenuate memory deficits and neuronal damage after ischemia may be beneficial in cerebrovascular type dementia.

  20. Cerebellar networks with the cerebral cortex and basal ganglia.

    Science.gov (United States)

    Bostan, Andreea C; Dum, Richard P; Strick, Peter L

    2013-05-01

    The dominant view of cerebellar function has been that it is exclusively concerned with motor control and coordination. Recent findings from neuroanatomical, behavioral, and imaging studies have profoundly changed this view. Neuroanatomical studies using virus transneuronal tracers have demonstrated that cerebellar output reaches vast areas of the neocortex, including regions of prefrontal and posterior parietal cortex. Furthermore, it has recently become clear that the cerebellum is reciprocally connected with the basal ganglia, which suggests that the two subcortical structures are part of a densely interconnected network. Taken together, these findings elucidate the neuroanatomical substrate for cerebellar involvement in non-motor functions mediated by the prefrontal and posterior parietal cortex, as well as in processes traditionally associated with the basal ganglia. PMID:23579055

  1. Functional properties of GABA synaptic inputs onto GABA neurons in monkey prefrontal cortex

    NARCIS (Netherlands)

    D.C. Rotaru (Diana C.); C. Olezene (Cameron); T. Miyamae (Takeaki); N.V. Povysheva (Nadezhda V.); A.V. Zaitsev (Aleksey V.); D.A. Lewis (David A.); G. Gonzalez-Burgos (Guillermo)

    2015-01-01

    textabstractIn rodent cortex GABAA receptor (GABAAR)-mediated synapses are a significant source of input onto GABA neurons, and the properties of these inputs vary among GABA neuron subtypes that differ in molecular markers and firing patterns. Some features of cortical interne

  2. Executive function and cerebral blood flow on dorsolateral prefrontal cortex in cases of subcortical infarction

    International Nuclear Information System (INIS)

    In order to clarify the extent of dysexecutive function of patients with subcortical infarctions, participants of this study underwent neuropsychological tests and single photon emission computerized tomography (SPECT). These participants were categorized into two groups; patients with basal ganglia lesions (BG group) (n=5) and those with white matter lesions (WM group) (n=12). Participants were administered executive function tests as a part of a comprehensive neuropsychological battery. Administered executive measures included the Wisconsin Card Sorting Test (WCST), the Ruff Figural Fluency Test (RFFT), the Controlled Oral Word Association Test (COWAT), and the Trait Making Test; Parts A and B. There were no group differences in their age, years of education and global cognitive performance. Student's t-tests were conducted to determine group differences in executive function. As a result, the number of total errors, the number of perseverative errors and the number of categories completed on the WCST were significantly worse for the BG group than for the WM group. These groups did not differ on other measures administered. In addition, all participants underwent SPECT, and their results were compared with the normal control data. Hypoperfusion was found on parts of the bilateral frontal, temporal, and parietal lobes for the BG and WM groups. These tendencies stood out in the right hemisphere of the BG group. The BG group exhibited decreased cerebral blood flow (CBF) on the area of right side dorsolateral prefrontal cortex (DLPFC) (e.g., Brodmann area 44). These analyses revealed that individuals with BG lesions showed significant executive declines that might be associated with decreased CBF in the subcortical-frontal system. It may support the idea that BG is connected with DLPFC via frontal-subcortical neuronal circuit. Patients with BG lesions may experience dysexecutive function due to the phenomenon of diaschisis from the disruption of this circuit. (author)

  3. Molecular and histological changes in cerebral cortex and lung tissues under the effect of tramadol treatment.

    Science.gov (United States)

    Awadalla, Eatemad A; Salah-Eldin, Alaa-Eldin

    2016-08-01

    Tramadol abuse is one of the most frequent health problems in Egypt and worldwide. In most cases, tramadol abused by men face a problem with premature ejaculation. Tramadol like other opioids induces a decrease in plasma antioxidant levels, which may reflect a failure of the antioxidant defense mechanism against oxidative damage. The present work aimed to study the possible deleterious effects of oral administration of tramadol on brain and lung tissues in rats. Twenty adult male albino rats were divided into two groups; a control administered with normal saline and tramadol-treated (40mg/kg b.w.) group for 20 successive days. At the end of experimental period, blood was collected and specimens from brains and lungs were taken for histopathological and molecular studies. Malondialdehyde (MDA), reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) activities were measured in serum of control and tramadol-treated groups. Brain and lung specimens were histopathological evaluated using light microscopy. The expression levels of apoptotic related genes; Bcl-2, Bax and Caspase-3 were study in brain and lung tissues using RT-PCR analysis. We recorded a significant increase MDA level, while antioxidant enzymes; GSH, SOD and CAT were significantly decreased after tramadol-treatment. The obtained results revealed that tramadol induced a remarkable histomorphological changes in rats' brains (cerebral cortex and hippocampus) and severe histopathological changes in rats' lung when compared to that of control. On molecular level, the expression of the pro-apoptotic Bax and Caspase-3 showed a significant increase whereas the anti-apoptotic Bcl-2 decreased markedly indicating that tramadol is harmful at cellular level and can induce apoptotic changes in brain tissues. Our data confirmed the risk of increased oxidative stress, neuronal and pulmonary damage due to tramadol abuse. Although tramadol is reported to be effective in pain management, its toxicity should

  4. Molecular and histological changes in cerebral cortex and lung tissues under the effect of tramadol treatment.

    Science.gov (United States)

    Awadalla, Eatemad A; Salah-Eldin, Alaa-Eldin

    2016-08-01

    Tramadol abuse is one of the most frequent health problems in Egypt and worldwide. In most cases, tramadol abused by men face a problem with premature ejaculation. Tramadol like other opioids induces a decrease in plasma antioxidant levels, which may reflect a failure of the antioxidant defense mechanism against oxidative damage. The present work aimed to study the possible deleterious effects of oral administration of tramadol on brain and lung tissues in rats. Twenty adult male albino rats were divided into two groups; a control administered with normal saline and tramadol-treated (40mg/kg b.w.) group for 20 successive days. At the end of experimental period, blood was collected and specimens from brains and lungs were taken for histopathological and molecular studies. Malondialdehyde (MDA), reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) activities were measured in serum of control and tramadol-treated groups. Brain and lung specimens were histopathological evaluated using light microscopy. The expression levels of apoptotic related genes; Bcl-2, Bax and Caspase-3 were study in brain and lung tissues using RT-PCR analysis. We recorded a significant increase MDA level, while antioxidant enzymes; GSH, SOD and CAT were significantly decreased after tramadol-treatment. The obtained results revealed that tramadol induced a remarkable histomorphological changes in rats' brains (cerebral cortex and hippocampus) and severe histopathological changes in rats' lung when compared to that of control. On molecular level, the expression of the pro-apoptotic Bax and Caspase-3 showed a significant increase whereas the anti-apoptotic Bcl-2 decreased markedly indicating that tramadol is harmful at cellular level and can induce apoptotic changes in brain tissues. Our data confirmed the risk of increased oxidative stress, neuronal and pulmonary damage due to tramadol abuse. Although tramadol is reported to be effective in pain management, its toxicity should

  5. The linearity and selectivity of neuronal responses in awake visual cortex

    OpenAIRE

    Chen, Yao; Anand, Sanjiv; Martinez-Conde, Susana; Macknik, Stephen L.; Bereshpolova, Yulia; Swadlow, Harvey A.; Alonso, Jose-Manuel

    2009-01-01

    Neurons in primary visual cortex (V1) are frequently classified based on their response linearity: the extent in which their visual responses to drifting gratings resemble a linear replica of the stimulus. This classification is supported by the finding that response linearity is bimodally distributed across neurons in area V1 of anesthetized animals. However, recent studies suggest that such bimodal distribution may not reflect two neuronal types but a nonlinear relationship between the memb...

  6. Encoding of Rules by Neurons in the Human Dorsolateral Prefrontal Cortex

    OpenAIRE

    Matthew K Mian; Sheth, Sameer A.; Patel, Shaun R.; Spiliopoulos, Konstantinos,; Eskandar, Emad N.; Ziv M Williams

    2012-01-01

    We use rules to extend learned behavior beyond specific instances to general scenarios. The prefrontal cortex (PFC) is thought to play an important role in representing rules, as evidenced by subjects who have difficulty in following rules after PFC damage and by animal studies demonstrating rule sensitivity of individual PFC neurons. How rules are instantiated at the single-neuronal level in the human brain, however, remains unclear. Here, we recorded from individual neurons in the human dor...

  7. Knockdown of α-synuclein in cerebral cortex improves neural behavior associated with apoptotic inhibition and neurotrophin expression in spinal cord transected rats.

    Science.gov (United States)

    Wang, You-Cui; Feng, Guo-Ying; Xia, Qing-Jie; Hu, Yue; Xu, Yang; Xiong, Liu-Lin; Chen, Zhi-Wei; Wang, Hang-Ping; Wang, Ting-Hua; Zhou, Xue

    2016-04-01

    Spinal cord injury (SCI) often causes severe functional impairment with poor recovery. The treatment, however, is far from satisfaction, and the mechanisms remain unclear. By using proteomics and western blot, we found spinal cord transection (SCT) resulted in a significant down-regulation of α-synuclein (SNCA) in the motor cortex of SCT rats at 3 days post-operation. In order to detect the role of SNCA, we used SNCA-ORF/shRNA lentivirus to upregulate or knockdown SNCA expression. In vivo, SNCA-shRNA lentivirus injection into the cerebral cortex motor area not only inhibited SNCA expression, but also significantly enhanced neurons' survival, and attenuated neuronal apoptosis, as well as promoted motor and sensory function recovery in hind limbs. While, overexpression SNCA exhibited the opposite effects. In vitro, cortical neurons transfected with SNCA-shRNA lentivirus gave rise to an optimal neuronal survival and neurite outgrowth, while it was accompanied by reverse efficiency in SNCA-ORF group. In molecular level, SNCA silence induced the upregulation of Bcl-2 and the downregulation of Bax, and the expression of NGF, BDNF and NT3 was substantially upregulated in cortical neurons. Together, endogenous SNCA play a crucial role in motor and sensory function regulation, in which, the underlying mechanism may be linked to the regulation of apoptosis associated with apoptotic gene (Bax, Bcl2) and neurotrophic factors expression (NGF, BDNF and NT3). These finds provide novel insights to understand the role of SNCA in cerebral cortex after SCT, and it may be as a novel treatment target for SCI repair in future clinic trials. PMID:26822976

  8. Fractal dimension of apical dendritic arborization differs in the superficial and the deep pyramidal neurons of the rat cerebral neocortex.

    Science.gov (United States)

    Puškaš, Nela; Zaletel, Ivan; Stefanović, Bratislav D; Ristanović, Dušan

    2015-03-01

    Pyramidal neurons of the mammalian cerebral cortex have specific structure and pattern of organization that involves the presence of apical dendrite. Morphology of the apical dendrite is well-known, but quantification of its complexity still remains open. Fractal analysis has proved to be a valuable method for analyzing the complexity of dendrite morphology. The aim of this study was to establish the fractal dimension of apical dendrite arborization of pyramidal neurons in distinct neocortical laminae by using the modified box-counting method. A total of thirty, Golgi impregnated neurons from the rat brain were analyzed: 15 superficial (cell bodies located within lamina II-III), and 15 deep pyramidal neurons (cell bodies situated within lamina V-VI). Analysis of topological parameters of apical dendrite arborization showed no statistical differences except in total dendritic length (p=0.02), indicating considerable homogeneity between the two groups of neurons. On the other hand, average fractal dimension of apical dendrite was 1.33±0.06 for the superficial and 1.24±0.04 for the deep cortical neurons, showing statistically significant difference between these two groups (pfractal dimension values, apical dendrites of the superficial pyramidal neurons tend to show higher structural complexity compared to the deep ones.

  9. Amino acid incorporation into the protein of mitochondrial preparations from cerebral cortex and spinal cord.

    Science.gov (United States)

    Bachelard, H S

    1966-07-01

    1. Washed guinea-pig cerebral-cortex mitochondria incorporate [(14)C]leucine into their protein at a rate comparable with the rates reported for liver or heart mitochondria only if the mitochondria are separated from myelin and nerve endings by density-gradient centrifugation. 2. The non-mitochondrial components (myelin and nerve endings) of brain mitochondrial preparations incorporated [(14)C]leucine at a negligible rate. 3. The mitochondria do not require an exogenous supply of energy or a full supply of amino acids to support the process. 4. The incorporation rate was linear up to 2hr. aerobic incubation at 30 degrees and was inhibited by chloramphenicol, only slightly by actinomycin D and not by penicillin or pretreatment with ribonuclease. The observed incorporation is considered to be unlikely to be due to contaminating cytoplasmic ribosomes or bacteria. 5. The process was also studied in mitochondrial preparations from rabbit cerebral cortex and spinal cord.

  10. Berberine Inhibits the Release of Glutamate in Nerve Terminals from Rat Cerebral Cortex.

    Directory of Open Access Journals (Sweden)

    Tzu-Yu Lin

    Full Text Available Berberine, an isoquinoline plant alkaloid, protects neurons against neurotoxicity. An excessive release of glutamate is considered to be one of the molecular mechanisms of neuronal damage in several neurological diseases. In this study, we investigated whether berberine could affect endogenous glutamate release in nerve terminals of rat cerebral cortex (synaptosomes and explored the possible mechanism. Berberine inhibited the release of glutamate evoked by the K(+ channel blocker 4-aminopyridine (4-AP, and this phenomenon was prevented by the chelating extracellular Ca(2+ ions and the vesicular transporter inhibitor bafilomycin A1, but was insensitive to the glutamate transporter inhibitor DL-threo-beta-benzyl-oxyaspartate. Inhibition of glutamate release by berberine was not due to it decreasing synaptosomal excitability, because berberine did not alter 4-AP-mediated depolarization. The inhibitory effect of berberine on glutamate release was associated with a reduction in the depolarization-induced increase in cytosolic free Ca(2+ concentration. Involvement of the Cav2.1 (P/Q-type channels in the berberine action was confirmed by blockade of the berberine-mediated inhibition of glutamate release by the Cav2.1 (P/Q-type channel blocker ω-agatoxin IVA. In addition, the inhibitory effect of berberine on evoked glutamate release was prevented by the mitogen-activated/extracellular signal-regulated kinase kinase (MEK inhibitors. Berberine decreased the 4-AP-induced phosphorylation of extracellular signal-regulated kinase 1 and 2 (ERK1/2 and synapsin I, the main presynaptic target of ERK; this decrease was also blocked by the MEK inhibition. Moreover, the inhibitory effect of berberine on evoked glutamate release was prevented in nerve terminals from mice lacking synapsin I. Together, these results indicated that berberine inhibits glutamate release from rats cortical synaptosomes, through the suppression of presynaptic Cav2.1 channels and ERK

  11. LIN7A depletion disrupts cerebral cortex development, contributing to intellectual disability in 12q21-deletion syndrome.

    Directory of Open Access Journals (Sweden)

    Ayumi Matsumoto

    Full Text Available Interstitial deletion of 12q21 has been reported in four cases, which share several common clinical features, including intellectual disability (ID, low-set ears, and minor cardiac abnormalities. Comparative genomic hybridization (CGH analysis using the Agilent Human Genome CGH 180K array was performed with the genomic DNA from a two-year-old Japanese boy with these symptoms, as well as hypoplasia of the corpus callosum. Consequently, a 14 Mb deletion at 12q21.2-q21.33 (nt. 77 203 574-91 264 613 bp, which includes 72 genes, was detected. Of these, we focused on LIN7A, which encodes a scaffold protein that is important for synaptic function, as a possible responsible gene for ID, and we analyzed its role in cerebral cortex development. Western blotting analyses revealed that Lin-7A is expressed on embryonic day (E 13.5, and gradually increases in the mouse brain during the embryonic stage. Biochemical fractionation resulted in the enrichment of Lin-7A in the presynaptic fraction. Suppression of Lin-7A expression by RNAi, using in utero electroporation on E14.5, delayed neuronal migration on postnatal day (P 2, and Lin-7A-deficient neurons remained in the lower zone of the cortical plate and the intermediate zone. In addition, when Lin-7A was silenced in cortical neurons in one hemisphere, axonal growth in the contralateral hemisphere was delayed; development of these neurons was disrupted such that one half did not extend into the contralateral hemisphere after leaving the corpus callosum. Taken together, LIN7A is a candidate gene responsible for 12q21-deletion syndrome, and abnormal neuronal migration and interhemispheric axon development may contribute to ID and corpus callosum hypoplasia, respectively.

  12. Effects of acupoint versus non-acupoint electroacupuncture on cerebral cortical neuronal Bcl-2,Bax and caspase-3 expression in a rat model of focal cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Jun Wang; Junming Fan; Yongshu Dong; Xia Huang; Hongxia Zhang

    2008-01-01

    each group for specimen preparation. A brain tissue block comprising the frontal lobe and the occipital lobe was cut into five coronal sections of equal-thickness. Neuronal apoptosis was detected by the terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling technique. Expression levels of caspase-3, Bcl-2 and Bax were evaluated by immunohistochemistry.RESULTS: Compared with the sham-operated group, the model group exhibited significantly decreased Bcl-2 expression (P 0.05).CONCLUSION: Electroacupuncture by acpoint selection can up-regulate Bcl-2 expression and concomitantly inhibit caspase-3 and Bax expression, inhibiting neuronal poptosis in rat cerebral cortex following cerebral ischemia/reperfusion.

  13. Alteration of rat fetal cerebral cortex development after prenatal exposure to polychlorinated biphenyls

    OpenAIRE

    Naveau, Elise; Pinson, Anneline; GERARD, Arlette; Nguyen, Laurent; Charlier, Corinne; Thomé, Jean-Pierre; Zoeller, Robert Thomas; Bourguignon, Jean-Pierre; Parent, Anne-Simone

    2014-01-01

    Polychlorinated biphenyls (PCBs) are environmental contaminants that persist in environment and human tissues. Perinatal exposure to these endocrine disruptors causes cognitive deficits and learning disabilities in children. These effects may involve their ability to interfere with thyroid hormone (TH) action. We tested the hypothesis that developmental exposure to PCBs can concomitantly alter TH levels and TH-regulated events during cerebral cortex development: progenitor proliferation, cell...

  14. RTTN Mutations Link Primary Cilia Function to Organization of the Human Cerebral Cortex

    OpenAIRE

    Kheradmand Kia, Sima; Verbeek, Elly; Engelen, Erik; Schot, Rachel; Poot, Raymond A.; de Coo, Irenaeus F.M.; Lequin, Maarten H.; Poulton, Cathryn J.; Pourfarzad, Farzin; Grosveld, Frank G.; Brehm, António; de Wit, Marie Claire Y.; Oegema, Renske; Dobyns, William B.; Verheijen, Frans W.

    2012-01-01

    Polymicrogyria is a malformation of the developing cerebral cortex caused by abnormal organization and characterized by many small gyri and fusion of the outer molecular layer. We have identified autosomal-recessive mutations in RTTN, encoding Rotatin, in individuals with bilateral diffuse polymicrogyria from two separate families. Rotatin determines early embryonic axial rotation, as well as anteroposterior and dorsoventral patterning in the mouse. Human Rotatin has recently been identified ...

  15. Somatostatin content and receptors in the cerebral cortex of depressed and control subjects.

    OpenAIRE

    Charlton, B G; Leake, A; Wright, C.; Fairbairn, A F; McKeith, I G; Candy, J M; Ferrier, I. N.

    1988-01-01

    Somatostatin-like immunoreactivity is reduced in the cerebrospinal fluid in depression and this is presumed to reflect alterations in cerebral somatostatinergic systems. We have examined this hypothesis by measuring this immunoreactivity and somatostatin receptors in post-mortem cortical tissue from depressed patients and control subjects. There was no significant difference in the temporal and occipital cortex in somatostatin-like immunoreactivity or in somatostatin receptor affinity and bin...

  16. Effects of anisodamine on altered [Ca2+]i and cerebral cortex ultrastructure following acute cerebral ischemia/reperfusion injury in rabbits

    Institute of Scientific and Technical Information of China (English)

    Daixing Zhou; Chengye Zhan; Puzhen Deng

    2008-01-01

    /reperfusion groups were significantly increased, compared with the sham operation group (P < 0.01), and the levels of [Ca2+]I in the anisodamine group were remarkably less than the ischemia and ischemia/reperfusion groups (P < 0.01). Ultrastructural damage to the cortex was greatly aggravated with increasing levels of [Ca2+]I In the ischemia group, cortical neuronal membranes were fragmentally damaged, including the mitochondria and endoplasmic reticulum, as well as neurite swelling, and slight chromatin margination. In the ischemia/reperfusion group, the cellular membrane was ruptured with aggravated mitochondrial swelling, increased chromatin margination, obscure neurite structure, and the disappearance of endoplasmic reticulum. However, in the anisodamine group, cellular damage was obviously alleviated. The appearance and structure of cortical neurons was relatively normal, with intact cells. There was slight swelling of the mitochondria and endoplasmic reticulum, as well as mild chromatin margination.CONCLUSION: Cerebral tissue injury was related to increased [Ca2+]I levels following ischemia/ reperfusion. Anisodamine exhibited a protective role on acute cerebral ischemia/reperfusion injury by inhibiting the increase in [Ca2+]i levels.

  17. Application of alcian blue in the electron microscopic study of mouse and human cerebral cortex nerve cells.

    Science.gov (United States)

    Castejón, H V; Castejón, O J; Viloria, M E

    1976-01-01

    Alcian blue is a cationic dye which has been used in the histochemical field for the demonstration of polyanions especially carboxylated and sulphated. The results obtained in neurons when this dye was applied to human and mouse cerebral cortex and studied with the electron microscope are the object of the present report. The CNS of normal adult mice was fixed by vascular perfusion with 2% glutaraldehyde-0.1 M sodium cacodylate-0.1 M sucrose at pH = 6.8 followed by the same fixative with the addition of 0.5% alcian blue. After perfusion, brain cortex was taken out, sectioned into small blocks and immersed in a fresh similar mixture and subsequently in OSO4. Blocks were dehydrated and embedded in araldite. Ultrathin sections were doubly stained with uranyl and lead salts. Human brain cortex taken from patients with cerebral edema was fixed by immersion with 6.5% glutaraldehyde-0.1 M sodium phosphate, pH = 7.4 followed by embedding in warm agar and sectioning in slices of 30 mum thickness which were impregnated by immersion in a mixture of 1% alcian blue-acetate buffer-3% glutaraldehyde at pH = 3.5 for 9 to 15 h at 4 degrees C and subsequently immersed in 1% buffered OSO4-0.1 M sucrose, pH = 7.4 for 2 h at 4 degrees S. Sections were dehydrated and embedded in araldite. Ultrathin sections were doubly stained by uranyl and lead salts. We have denominated the complete procedure in both instances GABOUL technique. The submicroscopic study of both tissues, at nerve cells, revealed the presence of an electron dense homogeneous substance thoroughly dispersed at the hyaloplasmic matrix of perikarya, processes and even synaptic endings. This substance was more evident around free and attached ribosomes, GOLGI apparatus, complex vesicles, dense bodies, microtubules, subsurface cisternae and synaptic vesicles. Canaliculi of endoplasmic reticulum and even the perinuclear cistern also showed a moderate content. It is suggested that this electron dense substance, being

  18. The sparseness of neuronal responses in ferret primary visual cortex.

    Science.gov (United States)

    Tolhurst, David J; Smyth, Darragh; Thompson, Ian D

    2009-02-25

    Various arguments suggest that neuronal coding of natural sensory stimuli should be sparse (i.e., individual neurons should respond rarely but should respond reliably). We examined sparseness of visual cortical neurons in anesthetized ferret to flashed natural scenes. Response behavior differed widely between neurons. The median firing rate of 4.1 impulses per second was slightly higher than predicted from consideration of metabolic load. Thirteen percent of neurons (12 of 89) responded to 25% of images. Multivariate analysis of the range of sparseness values showed that 67% of the variance was accounted for by differing response patterns to moving gratings. Repeat presentation of images showed that response variance for natural images exaggerated sparseness measures; variance was scaled with mean response, but with a lower Fano factor than for the responses to moving gratings. This response variability and the "soft" sparse responses (Rehn and Sommer, 2007) raise the question of what constitutes a reliable neuronal response and imply parallel signaling by multiple neurons. We investigated whether the temporal structure of responses might be reliable enough to give additional information about natural scenes. Poststimulus time histogram shape was similar for "strong" and "weak" stimuli, with no systematic change in first-spike latency with stimulus strength. The variance of first-spike latency for repeat presentations of the same image was greater than the latency variance between images. In general, responses to flashed natural scenes do not seem compatible with a sparse encoding in which neurons fire rarely but reliably. PMID:19244512

  19. Morphology of Pyramidal Neurons in the Rat Prefrontal Cortex: Lateralized Dendritic Remodeling by Chronic Stress

    Directory of Open Access Journals (Sweden)

    Claudia Perez-Cruz

    2007-01-01

    Full Text Available The prefrontal cortex (PFC plays an important role in the stress response. We filled pyramidal neurons in PFC layer III with neurobiotin and analyzed dendrites in rats submitted to chronic restraint stress and in controls. In the right prelimbic cortex (PL of controls, apical and distal dendrites were longer than in the left PL. Stress reduced the total length of apical dendrites in right PL and abolished the hemispheric difference. In right infralimbic cortex (IL of controls, proximal apical dendrites were longer than in left IL, and stress eliminated this hemispheric difference. No hemispheric difference was detected in anterior cingulate cortex (ACx of controls, but stress reduced apical dendritic length in left ACx. These data demonstrate interhemispheric differences in the morphology of pyramidal neurons in PL and IL of control rats and selective effects of stress on the right hemisphere. In contrast, stress reduced dendritic length in the left ACx.

  20. Synaptic output of individual layer 4 neurons in guinea pig visual cortex

    OpenAIRE

    Sáez, Ignacio; Friedlander, Michael J.

    2009-01-01

    More than 90% of geniculocortical axons from the dorsal lateral geniculate nucleus of the thalamus innervate layer 4 (L4) of the primary visual cortex (V1). Excitatory neurons, which comprise over 80% of the neuronal population in L4, synapse mainly onto adjacent L4 neurons and layer 2/3 (L2/3) neurons. It has been suggested that intra-laminar L4-L4 connections contribute to amplifying and refining thalamocortical signals before routing to L2/3. In order to unambiguously probe the properties ...

  1. A dynamic code for economic object valuation in prefrontal cortex neurons.

    Science.gov (United States)

    Tsutsui, Ken-Ichiro; Grabenhorst, Fabian; Kobayashi, Shunsuke; Schultz, Wolfram

    2016-01-01

    Neuronal reward valuations provide the physiological basis for economic behaviour. Yet, how such valuations are converted to economic decisions remains unclear. Here we show that the dorsolateral prefrontal cortex (DLPFC) implements a flexible value code based on object-specific valuations by single neurons. As monkeys perform a reward-based foraging task, individual DLPFC neurons signal the value of specific choice objects derived from recent experience. These neuronal object values satisfy principles of competitive choice mechanisms, track performance fluctuations and follow predictions of a classical behavioural model (Herrnstein's matching law). Individual neurons dynamically encode both, the updating of object values from recently experienced rewards, and their subsequent conversion to object choices during decision-making. Decoding from unselected populations enables a read-out of motivational and decision variables not emphasized by individual neurons. These findings suggest a dynamic single-neuron and population value code in DLPFC that advances from reward experiences to economic object values and future choices. PMID:27618960

  2. A dynamic code for economic object valuation in prefrontal cortex neurons

    Science.gov (United States)

    Tsutsui, Ken-Ichiro; Grabenhorst, Fabian; Kobayashi, Shunsuke; Schultz, Wolfram

    2016-01-01

    Neuronal reward valuations provide the physiological basis for economic behaviour. Yet, how such valuations are converted to economic decisions remains unclear. Here we show that the dorsolateral prefrontal cortex (DLPFC) implements a flexible value code based on object-specific valuations by single neurons. As monkeys perform a reward-based foraging task, individual DLPFC neurons signal the value of specific choice objects derived from recent experience. These neuronal object values satisfy principles of competitive choice mechanisms, track performance fluctuations and follow predictions of a classical behavioural model (Herrnstein's matching law). Individual neurons dynamically encode both, the updating of object values from recently experienced rewards, and their subsequent conversion to object choices during decision-making. Decoding from unselected populations enables a read-out of motivational and decision variables not emphasized by individual neurons. These findings suggest a dynamic single-neuron and population value code in DLPFC that advances from reward experiences to economic object values and future choices. PMID:27618960

  3. A dynamic code for economic object valuation in prefrontal cortex neurons.

    Science.gov (United States)

    Tsutsui, Ken-Ichiro; Grabenhorst, Fabian; Kobayashi, Shunsuke; Schultz, Wolfram

    2016-09-13

    Neuronal reward valuations provide the physiological basis for economic behaviour. Yet, how such valuations are converted to economic decisions remains unclear. Here we show that the dorsolateral prefrontal cortex (DLPFC) implements a flexible value code based on object-specific valuations by single neurons. As monkeys perform a reward-based foraging task, individual DLPFC neurons signal the value of specific choice objects derived from recent experience. These neuronal object values satisfy principles of competitive choice mechanisms, track performance fluctuations and follow predictions of a classical behavioural model (Herrnstein's matching law). Individual neurons dynamically encode both, the updating of object values from recently experienced rewards, and their subsequent conversion to object choices during decision-making. Decoding from unselected populations enables a read-out of motivational and decision variables not emphasized by individual neurons. These findings suggest a dynamic single-neuron and population value code in DLPFC that advances from reward experiences to economic object values and future choices.

  4. Pine pollen inhibits cell apoptosis-related protein expression in the cerebral cortex of mice with arsenic poisoning.

    Science.gov (United States)

    Luo, Yanhong; Wei, Yaodong; Wang, Taizhong; Chen, Dongzhu; Lu, Tiansheng; Wu, Ruibo; Si, Keke

    2012-04-25

    Previous studies have demonstrated that pine pollen can inhibit cerebral cortical cell apoptosis in mice with arsenic poisoning. The present study sought to detect the influence of pine pollen on apoptosis-related proteins. Immunohistochemistry, western blotting and enzyme-linked immunosorbent assays were used to measure the levels of apoptosis-related proteins in the cerebral cortex of mice with arsenic poisoning. Results indicated that pine pollen suppressed cell apoptosis in the cerebral cortex of arsenic-poisoned mice by reducing Bax, Bcl-2 protein expression and increasing p53 protein expression.

  5. Pine pollen inhibits cell apoptosis-related protein expression in the cerebral cortex of mice with arsenic poisoning★

    Science.gov (United States)

    Luo, Yanhong; Wei, Yaodong; Wang, Taizhong; Chen, Dongzhu; Lu, Tiansheng; Wu, Ruibo; Si, Keke

    2012-01-01

    Previous studies have demonstrated that pine pollen can inhibit cerebral cortical cell apoptosis in mice with arsenic poisoning. The present study sought to detect the influence of pine pollen on apoptosis-related proteins. Immunohistochemistry, western blotting and enzyme-linked immunosorbent assays were used to measure the levels of apoptosis-related proteins in the cerebral cortex of mice with arsenic poisoning. Results indicated that pine pollen suppressed cell apoptosis in the cerebral cortex of arsenic-poisoned mice by reducing Bax, Bcl-2 protein expression and increasing p53 protein expression. PMID:25722672

  6. Pine pollen inhibits cell apoptosis-related protein expression in the cerebral cortex of mice with arsenic poisoning

    Institute of Scientific and Technical Information of China (English)

    Yanhong Luo; Yaodong Wei; Taizhong Wang; Dongzhu Chen; Tiansheng Lu; Ruibo Wu; Keke Si

    2012-01-01

    Previous studies have demonstrated that pine pollen can inhibit cerebral cortical cell apoptosis in mice with arsenic poisoning. The present study sought to detect the influence of pine pollen on apoptosis-related proteins. Immunohistochemistry, western blotting and enzyme-linked immuno-sorbent assays were used to measure the levels of apoptosis-related proteins in the cerebral cortex of mice with arsenic poisoning. Results indicated that pine pollen suppressed cell apoptosis in the cerebral cortex of arsenic-poisoned mice by reducing Bax, Bcl-2 protein expression and increasing p53 protein expression.

  7. Online learning and stimulus-driven responses of neurons in visual cortex

    OpenAIRE

    Tang, Huajin; Li, Haizhou; Yi, Zhang

    2010-01-01

    In understanding how visual scene is processed in visual cortex, it has been an intriguing problem for theoretical and experimental neuroscientists to examine the relationship between visual stimuli and the induced responses of visual cortex. In particular, it is less explored whether and how the collective responses of visual neurons are patterned to reflect the geometrical regularities. In this paper, through a computation model and statistical analysis, we show that the orientation prefere...

  8. Response of the sensorimotor cortex of cerebral palsy rats receiving transplantation of vascular endothelial growth factor 165-transfected neural stem cells

    Institute of Scientific and Technical Information of China (English)

    Jielu Tan; Xiangrong Zheng; Shanshan Zhang; Yujia Yang; Xia Wang; Xiaohe Yu; Le Zhong

    2014-01-01

    Neural stem cells are characterized by the ability to differentiate and stably express exogenous ge-nes. Vascular endothelial growth factor plays a role in protecting local blood vessels and neurons of newborn rats with hypoxic-ischemic encephalopathy. Transplantation of vascular endothelial growth factor-transfected neural stem cells may be neuroprotective in rats with cerebral palsy. In this study, 7-day-old Sprague-Dawley rats were divided into ifve groups: (1) sham operation (control), (2) cerebral palsy model alone or with (3) phosphate-buffered saline, (4) vascular en-dothelial growth factor 165 + neural stem cells, or (5) neural stem cells alone. hTe cerebral palsy model was established by ligating the letf common carotid artery followed by exposure to hypox-ia. Phosphate-buffered saline, vascular endothelial growth factor + neural stem cells, and neural stem cells alone were administered into the sensorimotor cortex using the stereotaxic instrument and microsyringe. Atfer transplantation, the radial-arm water maze test and holding test were performed. Immunohistochemistry for vascular endothelial growth factor and histology using hematoxylin-eosin were performed on cerebral cortex. Results revealed that the number of vas-cular endothelial growth factor-positive cells in cerebral palsy rats transplanted with vascular endothelial growth factor-transfected neural stem cells was increased, the time for ifnding water and the ifnding repetitions were reduced, the holding time was prolonged, and the degree of cell degeneration or necrosis was reduced. hTese ifndings indicate that the transplantation of vascu-lar endothelial growth factor-transfected neural stem cells alleviates brain damage and cognitive deifcits, and is neuroprotective in neonatal rats with hypoxia ischemic-mediated cerebral palsy.

  9. Environmental enrichment improves response strength, threshold, selectivity, and latency of auditory cortex neurons.

    Science.gov (United States)

    Engineer, Navzer D; Percaccio, Cherie R; Pandya, Pritesh K; Moucha, Raluca; Rathbun, Daniel L; Kilgard, Michael P

    2004-07-01

    Over the last 50 yr, environmental enrichment has been shown to generate more than a dozen changes in brain anatomy. The consequences of these physical changes on information processing have not been well studied. In this study, rats were housed in enriched or standard conditions either prior to or after reaching sexual maturity. Evoked potentials from awake rats and extracellular recordings from anesthetized rats were used to document responses of auditory cortex neurons. This report details several significant, new findings about the influence of housing conditions on the responses of rat auditory cortex neurons. First, enrichment dramatically increases the strength of auditory cortex responses. Tone-evoked potentials of enriched rats, for example, were more than twice the amplitude of rats raised in standard laboratory conditions. Second, cortical responses of both young and adult animals benefit from exposure to an enriched environment and are degraded by exposure to an impoverished environment. Third, housing condition resulted in rapid remodeling of cortical responses in <2 wk. Fourth, recordings made under anesthesia indicate that enrichment increases the number of neurons activated by any sound. This finding shows that the evoked potential plasticity documented in awake rats was not due to differences in behavioral state. Finally, enrichment made primary auditory cortex (A1) neurons more sensitive to quiet sounds, more selective for tone frequency, and altered their response latencies. These experiments provide the first evidence of physiologic changes in auditory cortex processing resulting from generalized environmental enrichment.

  10. Inflammation and neuronal death in the motor cortex of the wobbler mouse, an ALS animal model

    DEFF Research Database (Denmark)

    Dahlke, Carolin; Saberi, Darius; Ott, Bastian;

    2015-01-01

    An abnormal density of Iba-1-positive microglial cells expressing pro-inflammatory tumor necrosis factor (TNF) alpha- and glial fibrillary acidic protein (GFAP)-positive activated astroglial cells was detected in the motor cortex region of the WR mouse 40 days postnatal (d.p.n.). Motor neurons in the same...... be an important contributing factor of motor neuron degeneration. This would appear to be confirmed by the fact that there was no conspicuous increase of microglial cells and astrocytes in the motor cortex of control mice at any time. Conclusions Activated microglial cells secrete a variety of pro...

  11. Computational modeling of direct neuronal recruitment during intracortical microstimulation in somatosensory cortex

    Science.gov (United States)

    Overstreet, C. K.; Klein, J. D.; Helms Tillery, S. I.

    2013-12-01

    Objective. Electrical stimulation of cortical tissue could be used to deliver sensory information as part of a neuroprosthetic device, but current control of the location, resolution, quality, and intensity of sensations elicited by intracortical microstimulation (ICMS) remains inadequate for this purpose. One major obstacle to resolving this problem is the poor understanding of the neural activity induced by ICMS. Even with new imaging methods, quantifying the activity of many individual neurons within cortex is difficult. Approach. We used computational modeling to examine the response of somatosensory cortex to ICMS. We modeled the axonal arbors of eight distinct morphologies of interneurons and seven types of pyramidal neurons found in somatosensory cortex and identified their responses to extracellular stimulation. We then combined these axonal elements to form a multi-layered slab of simulated cortex and investigated the patterns of neural activity directly induced by ICMS. Specifically we estimated the number, location, and variety of neurons directly recruited by stimulation on a single penetrating microelectrode. Main results. The population of neurons activated by ICMS was dependent on both stimulation strength and the depth of the electrode within cortex. Strikingly, stimulation recruited interneurons and pyramidal neurons in very different patterns. Interneurons are primarily recruited within a dense, continuous region around the electrode, while pyramidal neurons were recruited in a sparse fashion both near the electrode and up to several millimeters away. Thus ICMS can lead to an unexpectedly complex spatial distribution of firing neurons. Significance. These results lend new insights to the complexity and range of neural activity that can be induced by ICMS. This work also suggests mechanisms potentially responsible for the inconsistency and unnatural quality of sensations initiated by ICMS. Understanding these mechanisms will aid in the design of

  12. Diversity of Layer 5 Projection Neurons in the Mouse Motor Cortex

    Directory of Open Access Journals (Sweden)

    Manfred J Oswald

    2013-10-01

    Full Text Available In the primary motor cortex (M1, layer 5 projection neurons signal directly to distant motor structures to drive movement. Despite their pivotal position and acknowledged diversity these neurons are traditionally separated into broad commissural and corticofugal types, and until now no attempt has been made at resolving the basis for their diversity. We therefore probed the electrophysiological and morphological properties of retrogradely labelled M1 corticospinal (CSp, corticothalamic (CTh, and commissural projecting corticostriatal (CStr and corticocortical (CC neurons. An unsupervised cluster analysis established at least four phenotypes with additional differences between lumbar and cervical projecting CSp neurons. Distinguishing parameters included the action potential (AP waveform, firing behaviour, the hyperpolarisation-activated sag potential, sublayer position, and soma and dendrite size. CTh neurons differed from CSp neurons in showing spike frequency acceleration and a greater sag potential. CStr neurons had the lowest AP amplitude and maximum rise rate of all neurons. Temperature influenced spike train behaviour in corticofugal neurons. At 26 ºC CTh neurons fired bursts of APs more often than CSp neurons, but at 36 ºC both groups fired regular APs. Our findings provide reliable phenotypic fingerprints to identify distinct M1 projection neuron classes as a tool to understand their unique contributions to motor function.

  13. Calcium-binding protein-containing neuronal populations in mammalian visual cortex: a comparative study in whales, insectivores, bats, rodents, and primates.

    Science.gov (United States)

    Glezer, I I; Hof, P R; Leranth, C; Morgane, P J

    1993-01-01

    This study is focused on comparative analysis of gamma-aminobutyric acid-positive (GABAergic) neuronal populations in primary visual cortex of totally aquatic toothed whales and select terrestrial mammals with different evolutionary histories and various ecological adaptations. The distribution of neuronal populations containing the calcium-binding proteins calbindin and parvalbumin, which are recognized markers for the GABAergic neurons in cerebral cortex, is compared in five species of toothed whales and in representatives (one species each) of insectivores, bats, rodents, and primates. Computerized image analysis has shown that overall quantitative characteristics of GABAergic cortical neurons in toothed whales are similar to those in other mammalian orders. Thus, GABA-positive neurons represent 26% of the total population of cortical neurons in the visual cortex of whales. Some 97% of GABA-positive cells contain calcium-binding proteins, which is numerically similar to these parameters found in primates and other mammals. On the other hand, the typology and laminar distribution of calcium-binding protein-containing neurons in the primary visual cortex of five whale species (Delphinapterus leucas, Globicephala melaena, Phocoena phocoena, Stenella coeruleoalba, and Tursiops truncatus) differ significantly from those of primates (Macaca mulatta) and rodents (Rattus rattus) and are similar to those found in insectivorous bats (Eptesicus fuscus) and hedgehogs (Erinaceus europaeus). In whales, bats, and hedgehogs a significant concentration of calbindin-positive, vertically oriented bipolar and bitufted neurons was found in layers I, II, and IIIc/V with their axons arranged in a three-dimensional network. In primates and rodents they are distributed evenly across all cortical layers and are predominantly multipolar or bitufted neurons found in all cortical layers with their axons oriented along the vertical axis of the cortical plate. The parvalbumin-positive neurons

  14. Microcircuits of excitatory and inhibitory neurons in layer 2/3 of mouse barrel cortex

    OpenAIRE

    Avermann, Michael; Tomm, Christian; Mateo, Celine; Gerstner, Wulfram; Petersen, Carl C. H.

    2012-01-01

    Avermann M, Tomm C, Mateo C, Gerstner W, Petersen CC. Microcircuits of excitatory and inhibitory neurons in layer 2/3 of mouse barrel cortex. J Neurophysiol 107: 3116-3134, 2012. First published March 7, 2012; doi:10.1152/jn.00917.2011.-Synaptic interactions between nearby excitatory and inhibitory neurons in the neocortex are thought to play fundamental roles in sensory processing. Here, we have combined optogenetic stimulation, whole cell recordings, and computational modeling to define key...

  15. Diversity of layer 5 projection neurons in the mouse motor cortex

    OpenAIRE

    Oswald, Manfred J.; Tantirigama, Malinda L. S.; Sonntag, Ivo; Hughes, Stephanie M.; Ruth M Empson

    2013-01-01

    In the primary motor cortex (M1), layer 5 projection neurons signal directly to distant motor structures to drive movement. Despite their pivotal position and acknowledged diversity these neurons are traditionally separated into broad commissural and corticofugal types, and until now no attempt has been made at resolving the basis for their diversity. We therefore probed the electrophysiological and morphological properties of retrogradely labeled M1 corticospinal (CSp), corticothalamic (CTh)...

  16. Diversity of Layer 5 Projection Neurons in the Mouse Motor Cortex

    OpenAIRE

    Oswald, Manfred J.; Malinda LS Tantirigama; Ivo eSonntag; Hughes, Stephanie M.; Ruth M Empson

    2013-01-01

    In the primary motor cortex (M1), layer 5 projection neurons signal directly to distant motor structures to drive movement. Despite their pivotal position and acknowledged diversity these neurons are traditionally separated into broad commissural and corticofugal types, and until now no attempt has been made at resolving the basis for their diversity. We therefore probed the electrophysiological and morphological properties of retrogradely labelled M1 corticospinal (CSp), corticothalamic (CTh...

  17. Morphology and Physiology of Excitatory Neurons in Layer 6b of the Somatosensory Rat Barrel Cortex

    OpenAIRE

    M. Marx; Feldmeyer, D.

    2012-01-01

    Neocortical lamina 6B (L6B) is a largely unexplored layer with a very heterogeneous cellular composition. To date, only little is known about L6B neurons on a systematic and quantitative basis. We investigated the morphological and electrophysiological properties of excitatory L6B neurons in the rat somatosensory barrel cortex using whole-cell patch-clamp recordings and simultaneous biocytin fillings. Subsequent histological processing and computer-assisted 3D reconstructions provided the bas...

  18. Compact movable microwire array for long-term chronic unit recording in cerebral cortex of primates.

    Science.gov (United States)

    Jackson, Andrew; Fetz, Eberhard E

    2007-11-01

    We describe a small, chronically implantable microwire array for obtaining long-term unit recordings from the cortex of unrestrained nonhuman primates. After implantation, the depth of microwires can be individually adjusted to maintain large-amplitude action potential recordings from single neurons over many months. We present data recorded from the primary motor cortex of two monkeys by autonomous on-board electronic circuitry. Waveforms of individual neurons remained stable for recording periods of several weeks during unrestrained behavior. Signal-to-noise ratios, waveform stability, and rates of cell loss indicate that this method may be particularly suited to experiments investigating the neural correlates of processes extending over multiple days, such as learning and plasticity. PMID:17855584

  19. Lower neuronal variability in the monkey dorsolateral prefrontal than posterior parietal cortex.

    Science.gov (United States)

    Qi, Xue-Lian; Constantinidis, Christos

    2015-10-01

    The dorsolateral prefrontal and posterior parietal cortex are two brain areas involved in cognitive functions such as spatial attention and working memory. When tested with identical tasks, only subtle differences in firing rate are present between neurons recorded in the two areas. In this article we report that major differences in neuronal variability characterize the two areas during working memory. The Fano factors of spike counts in dorsolateral prefrontal neurons were consistently lower than those of the posterior parietal cortex across a range of tasks, epochs, and conditions in the same monkeys. Variability differences were observed despite minor differences in firing rates between the two areas in the tasks tested and higher overall firing rate in the prefrontal than in the posterior parietal sample. Other measures of neuronal discharge variability, such as the coefficient of variation of the interspike interval, displayed the same pattern of lower prefrontal variability. Fano factor values were negatively correlated with performance in the working memory task, suggesting that higher neuronal variability was associated with diminished task performance. The results indicate that information involving remembered stimuli is more reliably represented in the prefrontal than the posterior parietal cortex based on the variability of neuronal responses, and suggest functional differentiation between the two areas beyond differences in firing rate. PMID:26269556

  20. Effects of melatonin on learning abilities, cholinergic fibers and nitric oxide synthase expression in rat cerebral cortex

    Institute of Scientific and Technical Information of China (English)

    Bin Xu; Junpao Chen; Hailing Zhao

    2006-01-01

    BACKGROUND: Melatonin is a kind of hormones derived from pineal gland. Recent researches demonstrate that melatonin is characterized by anti-oxidation, anti-senility and destroying free radicals. While, effect and pathogenesis of pineal gland on learning ability should be further studied.OBJ ECTIVE: To investigate the effects of pinealectomy on learning abiliy, distribution of cholinesterase and expression of neuronal nitric oxide synthase (nNOS) in cerebral cortex of rats and probe into the effect of melatonin on learning ability, central cholinergic system and nNOS expression.DESIGN: Randomized grouping design and animal study.SETTING: Department of Neurology, the 187 Hospital of Chinese PLA.MATERIALS: A total of 12 male SD rats, of normal learning ability testing with Y-tape maze, of clean grade,weighing 190-210 g, aged 6 weeks, were selected in this study.METHODS: The experiment was carried out in the Department of Neurology, Zhujiang Hospital from July 1997to June 2000. All SD rats were divided into experimental group (n =6,pinealectomy) and control group (n =6, sham operation). Seven days later, rats in both two groups were continuously fed for 33 days. ①Learning ability test: The learning ability of rats was tested by trisection Y-type maze and figured as attempting times. ②Expression of acetylcholinesterase (AchE) was detected by enzyme histochemistry and nNOS was measured by SABC method. ③ Quantitative analysis of AchE fibers: AchE fibers density in unit area (surface density)was surveyed with Leica Diaplan microscope and Leica Quantimet 500+ image analytic apparatus and quantitative parameter was set up for AchE fibers covering density (μm2) per 374 693.656 μm2, moreover, the AchE fibers density was measured in Ⅱ -Ⅳ layers of motor and somatosensory cortex (showing three layers per field of vision at one time), in radiative, lacunaria and molecular layers of CA1, CA2 and CA3 areas, and in lamina multiforms of dentate gyrus. Three tissue slices

  1. Ganoderma lucidum spore powder modulates Bcl-2 and Bax expression in the hippocampus and cerebral cortex, and improves learning and memory in pentylenetetrazole-kindled rats

    Institute of Scientific and Technical Information of China (English)

    Shuang Zhao; Shengchang Zhang; Shuqiu Wang

    2011-01-01

    We studied the effects of Ganoderma lucidum spore powder on Bax and Bcl-2 expression and neuronal apoptosis in pentylenetetrazole-kindled epileptic rats. Sixty adult rats were randomly divided into a control group, an epileptic group (kindled) and three medication groups ( 150, 300,450 mg/kg given to kindled rats). Bax and Bcl-2 immunohistochemistry and TUNEL labeling show ed that the number of Bax- and TUNEL-positive cells in the hippocampus and cerebral cortex decreased significantly in the high-dose medication group, while the number of Bcl-2immunoreactive cells increased. The Morris water maze test showed that high-dose treatment significantly shortened escape latency and increased spatial probe trial performance. Our findings indicate that a high dose of Ganoderma lucidum spore powder upregulates the expressionof antiapoptotic Bcl-2 protein in the hippocampus and cerebral cortex, inhibits proapoptotic Bax expression, and decreases seizure-induced neuronal apoptosis. Further,Ganoderma lucidum appears to protect against epilepsy-related learning and memory impairments.

  2. Maternal Exercise during Pregnancy Increases BDNF Levels and Cell Numbers in the Hippocampal Formation but Not in the Cerebral Cortex of Adult Rat Offspring.

    Directory of Open Access Journals (Sweden)

    Sérgio Gomes da Silva

    Full Text Available Clinical evidence has shown that physical exercise during pregnancy may alter brain development and improve cognitive function of offspring. However, the mechanisms through which maternal exercise might promote such effects are not well understood. The present study examined levels of brain-derived neurotrophic factor (BDNF and absolute cell numbers in the hippocampal formation and cerebral cortex of rat pups born from mothers exercised during pregnancy. Additionally, we evaluated the cognitive abilities of adult offspring in different behavioral paradigms (exploratory activity and habituation in open field tests, spatial memory in a water maze test, and aversive memory in a step-down inhibitory avoidance task. Results showed that maternal exercise during pregnancy increased BDNF levels and absolute numbers of neuronal and non-neuronal cells in the hippocampal formation of offspring. No differences in BDNF levels or cell numbers were detected in the cerebral cortex. It was also observed that offspring from exercised mothers exhibited better cognitive performance in nonassociative (habituation and associative (spatial learning mnemonic tasks than did offspring from sedentary mothers. Our findings indicate that maternal exercise during pregnancy enhances offspring cognitive function (habituation behavior and spatial learning and increases BDNF levels and cell numbers in the hippocampal formation of offspring.

  3. Retrograde Cerebral Perfusion Results in Better Perfusion to the Striatum Than the Cerebral Cortex During Deep Hypothermic Circulatory Arrest: A Microdialysis Study.

    Science.gov (United States)

    Liang, Meng-Ya; Chen, Guang-Xian; Tang, Zhi-Xian; Rong, Jian; Yao, Jian-ping; Wu, Zhong-Kai

    2016-03-01

    It remains controversial whether contemporary cerebral perfusion techniques, utilized during deep hypothermic circulatory arrest (DHCA), establish adequate perfusion to deep structures in the brain. This study aimed to investigate whether selective antegrade cerebral perfusion (SACP) or retrograde cerebral perfusion (RCP) can provide perfusion equally to various anatomical positions in the brain using metabolic evidence obtained from microdialysis. Eighteen piglets were randomly assigned to 40 min of circulatory arrest (CA) at 18°C without cerebral perfusion (DHCA group, n = 6) or with SACP (SACP group, n = 6) or RCP (RCP group, n = 6). Microdialysis parameters (glucose, lactate, pyruvate, and glutamate) were measured every 30 min in cortex and striatum. After 3 h of reperfusion, brain tissue was harvested for Western blot measurement of α-spectrin. After 40 min of CA, the DHCA group showed marked elevations of lactate and glycerol and a reduction in glucose in the microdialysis perfusate (all P spectrin expression in brain tissue were similar between cortex and striatum in the SACP group (all P > 0.05). In the RCP group, the cortex exhibited lower glucose, higher lactate, and higher glycerol in the perfusate and higher α-spectrin expression in brain tissue compared with the striatum (all P 0.05). In summary, SACP provided uniform and continuous cerebral perfusion to most anatomical sites in the brain, whereas RCP resulted in less sufficient perfusion to the cortex but better perfusion to the striatum. PMID:26333187

  4. Inorganic Arsenic Induces NRF2-Regulated Antioxidant Defenses in Both Cerebral Cortex and Hippocampus in Vivo.

    Science.gov (United States)

    Zhang, Yang; Duan, Xiaoxu; Li, Jinlong; Zhao, Shuo; Li, Wei; Zhao, Lu; Li, Wei; Nie, Huifang; Sun, Guifang; Li, Bing

    2016-08-01

    Inorganic arsenic is reported to induce the reactive oxygen species-mediated oxidative stress, which is supposed to be one of the main mechanisms of arsenic-related neurological diseases. Nuclear factor erythroid 2-related factor 2 (NRF2), a master regulator of antioxidant defense systems, up-regulates the expression of target genes to fight against oxidative damages caused by harmful substances, including metals. In the present study, mice were used as a model to investigate the oxidative stress levels and the expressions of NRF2-regulated antioxidant substances in both cerebral cortex and hippocampus with 5, 10 and 20 mg/kg NaAsO2 exposure intra-gastrically. Our results showed that acute NaAsO2 treatment resulted in decreased total anti-oxidative capacity (T-AOC) and increased maleic dialdehyde production in the nervous system. We also detected rapidly elevation of NRF2 protein levels by enhancement of Nrf2 transcription, especially at 20 mg/kg NaAsO2 exposure group. In the meantime, mRNA and protein levels of Nrf2 encoding antioxidant enzymes heme oxygenase-1 (HO-1), NAD(P)H: quinine oxidoreductase 1 (NQO1) and glutathione S-transferase (GST) were consistently elevated time- and dose-dependently both in the cerebral cortex and hippocampus. Taken together, the presence study demonstrated the activation of NRF2 pathway, an early antioxidant defensive response, in both cerebral cortex and hippocampus upon inorganic arsenic (iAs) exposure in vivo. A better knowledge on the roles of NRF2 pathway in maintaining cellular redox homeostasis would be helpful for the strategies on improvement of neurotoxicity related to this metalloid. PMID:27165637

  5. Comparative neuronal morphology of the cerebellar cortex in afrotherians, carnivores, cetartiodactyls, and primates

    Directory of Open Access Journals (Sweden)

    Bob eJacobs

    2014-04-01

    Full Text Available Although the basic morphological characteristics of neurons in the cerebellar cortex have been documented in several species, virtually nothing is known about the quantitative morphological characteristics of these neurons across different taxa. To that end, the present study investigated cerebellar neuronal morphology among eight different, large-brained mammalian species comprising a broad phylogenetic range: afrotherians (African elephant, Florida manatee, carnivores (Siberian tiger, clouded leopard, cetartiodactyls (humpback whale, giraffe and primates (human, common chimpanzee. Specifically, several neuron types (e.g., stellate, basket, Lugaro, Golgi, and granule neurons; N = 317 of the cerebellar cortex were stained with a modified rapid Golgi technique and quantified on a computer-assisted microscopy system. There was a 64-fold variation in brain mass across species in our sample (from clouded leopard to the elephant and a 103-fold variation in cerebellar volume. Most dendritic measures tended to increase with cerebellar volume. The cerebellar cortex in these species exhibited the trilaminate pattern common to all mammals. Morphologically, neuron types in the cerebellar cortex were generally consistent with those described in primates (Fox et al., 1967 and rodents (Palay and Chan-Palay, 1974, although there was substantial quantitative variation across species. In particular, Lugaro neurons in the elephant appeared to be disproportionately larger than those in other species. To explore potential quantitative differences in dendritic measures across species, MARSplines analyses were used to evaluate whether species could be differentiated from each other based on dendritic characteristics alone. Results of these analyses indicated that there were significant differences among all species in dendritic measures.

  6. Primary visual cortex volume and total neuron number are reduced in schizophrenia

    DEFF Research Database (Denmark)

    Dorph-Petersen, Karl-Anton; Pierri, Joseph H.; Wu, Qiang;

    2007-01-01

    with schizophrenia reported an increased density of neurons in the primary visual cortex (Brodmann's area 17, BA17). The observed changes in visual processing may thus be reflected in structural changes in the circuitry of BA17. To characterize the structural changes further we used stereological methods based...

  7. Effect of camphor essential oil on rat cerebral cortex activity as manifested by fractal dimension changes

    Directory of Open Access Journals (Sweden)

    Grbić G.

    2008-01-01

    Full Text Available The aim of our study was to investigate the effect of camphor essential oil on rat cerebral cortex activity by fractal analysis. Fractal dimension (FD values of the parietal electrocortical activity were calculated before and after intra-peritoneal administration of camphor essential oil (450-675 μl/kg in anesthetized rats. Camphor oil induced seizure-like activity with single and multiple spiking of high amplitudes in the parietal electrocorticogram and occasional clonic limb convulsions. The FD values of cortical activity after camphor oil administration increased on the average. Only FD values of cortical ECoG sequences were lower than those before camphor oil administration.

  8. Effect of. beta. -endorphin on catecholamine levels in rat hypothalamus and cerebral cortex

    Energy Technology Data Exchange (ETDEWEB)

    Slavnov, V.N.; Valueva, G.V.; Markov, V.V.; Luchitskii, E.V.

    1986-10-01

    The authors studied the effect of beta-endorphin on catecholamine concentrations in the hypothalmus and cerebral cortex in rats, as a contribution to the explanation of the mechanism of action of this peptide on certain pituitary trophic functions. Concentrations of dopamine, noradrenalin, and adrenalin were determined by a radioenzymatic method. A Mark 3 scintillation system was used for radiometric investigation of the samples. The results of these experiments indicate that beta-endorphin has a marked effect on brain catecholamine levels mainly in the hypothalamus.

  9. Hypoosmotic swelling modifies glutamate-glutamine cycle in the cerebral cortex and in astrocyte cultures

    OpenAIRE

    Hyzinski-García, María C.; Vincent, Melanie Y.; Haskew-Layton, Renée E.; Dohare, Preeti; Keller, Richard W.; Mongin, Alexander A.

    2011-01-01

    In our previous work, we found that perfusion of the rat cerebral cortex with hypoosmotic medium triggers massive release of the excitatory amino acid L-glutamate but decreases extracellular levels of L-glutamine (R.E. Haskew-Layton et al., PLoS ONE, 3: e3543). The release of glutamate was linked to activation of volume-regulated anion channels (VRAC), while mechanism(s) responsible for alterations in extracellular glutamine remained unclear. When mannitol was added to the hypoosmotic medium ...

  10. Numbers of specific types of neuron in layer IVab of cat striate cortex.

    OpenAIRE

    Solnick, B; Davis, T L; Sterling, P

    1984-01-01

    Layer IVab of the visual cortex (area 17) of the cat contains about 51,400 neurons per mm3, including about 400-1200 per mm3 of each of three categories of neuron believed from previous work to represent discrete types. Each type forms about 0.5-1.5% of all the IVab neurons, which suggests that the total number of types in this layer might be much greater than previously supposed, perhaps as many as 50 or more. From their densities and estimates of their dendritic fields, we calculate that ea...

  11. The spinothalamic system targets motor and sensory areas in the cerebral cortex of monkeys.

    Science.gov (United States)

    Dum, Richard P; Levinthal, David J; Strick, Peter L

    2009-11-11

    Classically, the spinothalamic (ST) system has been viewed as the major pathway for transmitting nociceptive and thermoceptive information to the cerebral cortex. There is a long-standing controversy about the cortical targets of this system. We used anterograde transneuronal transport of the H129 strain of herpes simplex virus type 1 in the Cebus monkey to label the cortical areas that receive ST input. We found that the ST system reaches multiple cortical areas located in the contralateral hemisphere. The major targets are granular insular cortex, secondary somatosensory cortex and several cortical areas in the cingulate sulcus. It is noteworthy that comparable cortical regions in humans consistently display activation when subjects are acutely exposed to painful stimuli. We next combined anterograde transneuronal transport of virus with injections of a conventional tracer into the ventral premotor area (PMv). We used the PMv injection to identify the cingulate motor areas on the medial wall of the hemisphere. This combined approach demonstrated that each of the cingulate motor areas receives ST input. Our meta-analysis of imaging studies indicates that the human equivalents of the three cingulate motor areas also correspond to sites of pain-related activation. The cingulate motor areas in the monkey project directly to the primary motor cortex and to the spinal cord. Thus, the substrate exists for the ST system to have an important influence on the cortical control of movement. PMID:19906970

  12. Autophagy:a double-edged sword for neuronal survival after cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Wenqi Chen; Yinyi Sun; Kangyong Liu; Xiaojiang Sun

    2014-01-01

    Evidence suggests that autophagy may be a new therapeutic target for stroke, but whether acti-vation of autophagy increases or decreases the rate of neuronal death is still under debate. This review summarizes the potential role and possible signaling pathway of autophagy in neuronal survival after cerebral ischemia and proposes that autophagy has dual effects.

  13. Upregulation of excitatory neurons and downregulation of inhibitory neurons in barrel cortex are associated with loss of whisker inputs

    OpenAIRE

    Zhang Guanjun; Gao Zilong; Guan Sudong; Zhu Yan; Wang Jin-Hui

    2013-01-01

    Abstract Loss of a sensory input causes the hypersensitivity in other modalities. In addition to cross-modal plasticity, the sensory cortices without receiving inputs undergo the plastic changes. It is not clear how the different types of neurons and synapses in the sensory cortex coordinately change after input deficits in order to prevent loss of their functions and to be used for other modalities. We studied this subject in the barrel cortices from whiskers-trimmed mice vs. controls. After...

  14. Neuronal representation of saccadic error in macaque posterior parietal cortex (PPC).

    Science.gov (United States)

    Zhou, Yang; Liu, Yining; Lu, Haidong; Wu, Si; Zhang, Mingsha

    2016-01-01

    Motor control, motor learning, self-recognition, and spatial perception all critically depend on the comparison of motor intention to the actually executed movement. Despite our knowledge that the brainstem-cerebellum plays an important role in motor error detection and motor learning, the involvement of neocortex remains largely unclear. Here, we report the neuronal computation and representation of saccadic error in macaque posterior parietal cortex (PPC). Neurons with persistent pre- and post-saccadic response (PPS) represent the intended end-position of saccade; neurons with late post-saccadic response (LPS) represent the actual end-position of saccade. Remarkably, after the arrival of the LPS signal, the PPS neurons' activity becomes highly correlated with the discrepancy between intended and actual end-position, and with the probability of making secondary (corrective) saccades. Thus, this neuronal computation might underlie the formation of saccadic error signals in PPC for speeding up saccadic learning and leading the occurrence of secondary saccade. PMID:27097103

  15. Melatonin reduces traumatic brain injur y-induced oxidative stress in the cerebral cortex and blood of rats

    Institute of Scientific and Technical Information of China (English)

    Nilgnenol; Mustafa Nazrolu

    2014-01-01

    Free radicals induced by traumatic brain injury have deleterious effects on the function and antioxidant vitamin levels of several organ systems including the brain. Melatonin possesses antioxidant effect on the brain by maintaining antioxidant enzyme and vitamin levels. We in-vestigated the effects of melatonin on antioxidant ability in the cerebral cortex and blood of traumatic brain injury rats. Results showed that the cerebral cortex β-carotene, vitamin C, vita-min E, reduced glutathione, and erythrocyte reduced glutathione levels, and plasma vitamin C level were decreased by traumatic brain injury whereas they were increased following melatonin treatment. In conclusion, melatonin seems to have protective effects on traumatic brain inju-ry-induced cerebral cortex and blood toxicity by inhibiting free radical formation and supporting antioxidant vitamin redox system.

  16. Effects of Cortical Spreading Depression on Synaptic Activity, Blood Flow and Oxygen Consumption in Rat Cerebral Cortex

    DEFF Research Database (Denmark)

    Hansen, Henning Piilgaard

    2010-01-01

    As the title of this thesis indicates I have during my PhD studied the effects of cortical spreading depression (CSD) on synaptic activity, blood flow and oxygen consumption in rat cerebral cortex. This was performed in vivo using an open cranial window approach in anesthetized rats. I applied...... Laser-Doppler Flowmetry for measurements of cerebral blood flow, glass microelectrodes for recording of synaptic activity – local field potentials – and ongoing cortical electrical activity and a Clark type electrode for measurements of tissue partial pressure of oxygen (tpO2). Offline calculations...... of cerebral metabolic rate of oxygen (CMRO2) were performed using a compartment model as described Gjedde1. In the first study we characterized the frequency dependency of evoked responses of the transcallosal fiber network (TC) in the somatosensory cortex concerning: synaptic activity, cerebral blood flow...

  17. Astrocytic response in hippocampus and cerebral cortex in an experimental epilepsy model.

    Science.gov (United States)

    Girardi, Elena; Ramos, Alberto Javier; Vanore, Gabriela; Brusco, Alicia

    2004-02-01

    Astrocytes are very sensitive to alterations in the brain environment and respond showing a phenomenon known as astroglial reaction. S100beta is an astroglial derived neurotrophic factor, seems to be involved in neuroplasticity. The aim of this work was to study the astrocytic response in rat hippocampus and cerebral cortex after repetitive seizures induced by 3-mercaptopropionic acid (MP) administration. Immunocytochemical studies were performed to analyze GFAP and S100beta expression. Both studied areas showed hypertrophied astrocytes with enlarged processes and increased soma size. Astrocyte hyperplasia was observed only in the cerebral cortex. A significant decrease in the astrocytic S100beta immunostaining occurs after MP treatment. These results indicate that MP administration induces an astroglial reaction with reduced intracellular S100beta level. The observed reduction in astroglial S100beta could be related to the release of this factor to the extracellular space, where it may produce neurotrophic or deleterious effects accordingly to the concentration achieved. The mechanism of this remains to be elucidated.

  18. Causal interactions between the cerebral cortex and the autonomic nervous system.

    Science.gov (United States)

    Yu, XiaoLin; Zhang, Chong; Zhang, JianBao

    2014-05-01

    Mental states such as stress and anxiety can cause heart disease. On the other hand, meditation can improve cardiac performance. In this study, the heart rate variability, directed transfer function and corrected conditional entropy were used to investigate the effects of mental tasks on cardiac performance, and the functional coupling between the cerebral cortex and the heart. When subjects tried to decrease their heart rate by volition, the sympathetic nervous system was inhibited and the heart rate decreased. When subjects tried to increase their heart rate by volition, the parasympathetic nervous system was inhibited and the sympathetic nervous system was stimulated, and the heart rate increased. When autonomic nervous system activity was regulated by mental tasks, the information flow from the post-central areas to the pre-central areas of the cerebral cortex increased, and there was greater coupling between the brain and the heart. Use of directed transfer function and corrected conditional entropy techniques enabled analysis of electroencephalographic recordings, and of the information flow causing functional coupling between the brain and the heart.

  19. Tyrosine administration decreases glutathione and stimulates lipid and protein oxidation in rat cerebral cortex.

    Science.gov (United States)

    Sgaravatti, Angela M; Magnusson, Alessandra S; de Oliveira, Amanda S; Rosa, Andréa P; Mescka, Caroline Paula; Zanin, Fernanda R; Pederzolli, Carolina D; Wyse, Angela T S; Wannmacher, Clóvis M D; Wajner, Moacir; Dutra-Filho, Carlos Severo

    2009-09-01

    Tyrosine levels are abnormally elevated in tissues and physiological fluids of patients with inborn errors of tyrosine catabolism especially in tyrosinemia type II which is caused by deficiency of tyrosine aminotransferase (TAT) and provokes eyes, skin and central nervous system disturbances. We have recently reported that tyrosine promoted oxidative stress in vitro but the exact mechanisms of brain damage in these disorder are poorly known. In the present study, we investigated the in vivo effect of L-tyrosine (500 mg/Kg) on oxidative stress indices in cerebral cortex homogenates of 14-day-old Wistar rats. A single injection of L-tyrosine decreased glutathione (GSH) and thiol-disulfide redox state (SH/SS ratio) while thiobarbituric acid-reactive substances, protein carbonyl content and glucose-6-phosphate dehydrogenase activity were enhanced. In contrast, the treatment did not affect ascorbic acid content, and the activities of superoxide dismutase, catalase and glutathione peroxidase. These results indicate that acute administration of L-tyrosine may impair antioxidant defenses and stimulate oxidative damage to lipids and proteins in cerebral cortex of young rats in vivo. This suggests that oxidative stress may represent a pathophysiological mechanism in hypetyrosinemic patients.

  20. Propofol Compared to Isoflurane Inhibits Mitochondrial Metabolism in Immature Swine Cerebral Cortex

    Energy Technology Data Exchange (ETDEWEB)

    Kajimoto, Masaki; Atkinson, D. B.; Ledee, Dolena R.; Kayser, Ernst-Bernhard; Morgan, Phil G.; Sedensky, Margaret M.; Isern, Nancy G.; Des Rosiers, Christine; Portman, Michael A.

    2014-01-08

    Anesthetics used in infants and children are implicated in development of neurocognitive disorders. Although propofol induces neuroapoptosis in developing brain, the underlying mechanisms require elucidation and may have an energetic basis. We studied substrate utilization in an immature swine model anesthetized with either propofol or isoflurane for 4 hours. Piglets were infused with 13-Carbon labeled glucose and leucine in the common carotid artery in order to assess citric acid cycle (CAC) metabolism in the parietal cortex. The anesthetics produced similar systemic hemodynamics and cerebral oxygen saturation by near-infrared-spectroscopy. Compared to isoflurane, propofol depleted ATP and glycogen stores. Propofol also decreased pools of the CAC intermediates, citrate and α-ketoglutarate, while markedly increasing succinate along with decreasing mitochondrial complex II activity. Propofol also inhibited acetyl-CoA entry into the CAC through pyruvate dehydrogenase, while promoting glycolytic flux with marked accumulation of lactate. Although oxygen supply appeared similar between the anesthetic groups, propofol yielded a metabolic phenotype which resembled a hypoxic state. Propofol impairs substrate flux through the CAC in the immature cerebral cortex. These impairments occurred without systemic metabolic perturbations which typically accompany propofol infusion syndrome. These metabolic abnormalities may play a role in neurotoxity observed with propofol in the vulnerable immature brain.

  1. Manatee cerebral cortex: cytoarchitecture of the caudal region in Trichechus manatus latirostris.

    Science.gov (United States)

    Marshall, C D; Reep, R L

    1995-01-01

    In several brains of the Florida manatee, Trichechus manatus latirostris, the architecture of caudal regions of cerebral cortex was examined in order to complete a map of cortical areas in the brain of this unique herbivore. Through observation of sections stained for Nissl substance, myelinated axons, acetylcholinesterase and cytochrome oxidase, we have identified 11 new cortical areas based on qualitative cytoarchitectural appearance and measurements of laminar thicknesses, for a total of 24 such cortical areas in manatee cerebral cortex. Some areas exhibit poorly differentiated laminae while in others there are 6 clearly demarcated layers, often with sublaminar organization. Some previously identified areas were found to extend into the region caudal to the vertically oriented lateral fissure. As in other mammalian brains, cortical areas in manatees are organized in concentric rings of allocortex, mesocortex, and isocortex. Putative functional roles have been assigned to most of the identified areas based on location, architecture, behavioral and anatomical considerations, and extrapolation from other taxa in which functional mapping has been done. PMID:7866767

  2. Effects of insulin-induced hypoglycemia on somatostatin level and binding in rat cerebral cortex and hippocampus

    OpenAIRE

    Rodríguez Sánchez, María Nelly; Colás Escudero, Begoña; Prieto Villapún, Juan Carlos; Arilla Ferreiro, Eduardo

    1989-01-01

    The effects of severe insulin-induced hypoglycemia on somatostatin level and specific binding in the cerebral cortex and hippocampus were examined using 125I-Tyr11-somatostatin as a ligand. Severe insulin-induced hypoglycemia did not affect the level of somatostatin-like immunoreactivity in the brain areas studied. However, the number (but not the affinity) of specific somatostatin receptors was significantly decreased in membrane preparation from the hippocampus but not in the cerebral corte...

  3. Safety of Direct Local Cooling (15° C) of the Cerebral Cortex with the Chillerstrip™ During Focal Cerebral Ischemia in Monkeys

    Science.gov (United States)

    Nemoto, Edwin M.; Jungreis, Charles; Jovin, Tudor; Rao, Gutti; Robinson, Timothy; Sanders, Todd; Casey, Kate; Kirkman, John

    Direct cooling of the cerebral cortex with the ChillerStrip™ to 15°C followed by spontaneous rewarming to 37°C is safe. Direct cooling of the brain reduces the severity of the ischemic insult as judged by the reduction in the hyperemia after reperfusion which appeared to be directly related to the temperature of the brain.

  4. Spatiotemporal characteristics of cerebral blood volume changes in different microvascular compartments evoked by sciatic nerve stimulation in rat somatosensory cortex

    Science.gov (United States)

    Li, Pengcheng; Luo, Qingming; Luo, Weihua; Chen, Shanbin; Cheng, Haiying; Zeng, Shaoqun

    2003-07-01

    The spatio-temporal characteristics of changes in cerebral blood volume associated with neuronal activity were investigated in the hindlimb somatosensory cortex of α-chloralose/urethan anesthetized rats (n=10) with optical imaging at 570nm through a thinned skull. Activation of cortex was carried out by electrical stimulation of the contralateral sciatic nerve with 5Hz, 0.3V pulses (0.5ms) for duration of 2s. The stimulation evoked a monophasic optical reflectance decrease at cortical parenchyma and arteries sites rapidly after the onset of stimulation, whereas no similar response was observed at vein compartments. The optical signal changes reached 10% of the peak response 0.70+/-0.32s after stimulation onset and no significant time lag in this 10% start latency time was observed between the response at cortical parenchyma and arteries compartments. The evoked optical reflectance decrease reached the peak (0.25%+/-0.047%) 2.66+/-0.61s after the stimulus onset at parenchyma site, 0.40+/-0.20s earlier (P<0.05) than that at arteries site (0.50+/-0.068% 3.06+/-0.70s). Variable location within the cortical parenchyma and arteries compartment themselves didn"t affect the temporal characteristics of the evoked signal significantly. These results suggest that the sciatic nerve stimulation evokes a local blood volume increase at both capillaries (cortical parenchyma) and arterioles rapidly after the stimulus onset but the evoked blood volume increase in capillaries could not be entirely accounted for by the dilation of arterioles.

  5. Orally Administrated Ascorbic Acid Suppresses Neuronal Damage and Modifies Expression of SVCT2 and GLUT1 in the Brain of Diabetic Rats with Cerebral Ischemia-Reperfusion

    Directory of Open Access Journals (Sweden)

    Naohiro Iwata

    2014-04-01

    Full Text Available Diabetes mellitus is known to exacerbate cerebral ischemic injury. In the present study, we investigated antiapoptotic and anti-inflammatory effects of oral supplementation of ascorbic acid (AA on cerebral injury caused by middle cerebral artery occlusion and reperfusion (MCAO/Re in rats with streptozotocin-induced diabetes. We also evaluated the effects of AA on expression of sodium-dependent vitamin C transporter 2 (SVCT2 and glucose transporter 1 (GLUT1 after MCAO/Re in the brain. The diabetic state markedly aggravated MCAO/Re-induced cerebral damage, as assessed by infarct volume and edema. Pretreatment with AA (100 mg/kg, p.o. for two weeks significantly suppressed the exacerbation of damage in the brain of diabetic rats. AA also suppressed the production of superoxide radical, activation of caspase-3, and expression of proinflammatory cytokines (tumor necrosis factor-α and interleukin-1β in the ischemic penumbra. Immunohistochemical staining revealed that expression of SVCT2 was upregulated primarily in neurons and capillary endothelial cells after MCAO/Re in the nondiabetic cortex, accompanied by an increase in total AA (AA + dehydroascorbic acid in the tissue, and that these responses were suppressed in the diabetic rats. AA supplementation to the diabetic rats restored these responses to the levels of the nondiabetic rats. Furthermore, AA markedly upregulated the basal expression of GLUT1 in endothelial cells of nondiabetic and diabetic cortex, which did not affect total AA levels in the cortex. These results suggest that daily intake of AA attenuates the exacerbation of cerebral ischemic injury in a diabetic state, which may be attributed to anti-apoptotic and anti-inflammatory effects via the improvement of augmented oxidative stress in the brain. AA supplementation may protect endothelial function against the exacerbated ischemic oxidative injury in the diabetic state and improve AA transport through SVCT2 in the cortex.

  6. Acupuncture at the Taixi (KI3) acupoint activates cerebral neurons in elderly patients with mild cognitive impairment

    Institute of Scientific and Technical Information of China (English)

    Shangjie Chen; Xuemin Shi; Lihua Zhao; Maosheng Xu; Hong Li; Jiuping Liang; Liang Yin; Xia Liu; Xinyan Jia; Fen Zhu; Dan Wang

    2014-01-01

    Our previous ifndings have demonstrated that acupuncture at the Taixi (KI3) acupoint in healthy youths can activate neurons in cognitive-related cerebral cortex. Here, we investigated whether acupuncture at this acupoint in elderly patients with mild cognitive impairment can also activate neurons in these regions. Resting state and task-related functional magnetic resonance imaging showed that the pinprick senstation of acupuncture at the Taixi acupoint differed signiifcantly between elderly patients with mild cognitive impairment and healthy elderly controls. Results showed that 20 brain regions were activated in both groups of participants, including the bi-lateral anterior cingulate gyrus (Brodmann areas [BA] 32, 24), left medial frontal cortex (BA 9, 10, 11), left cuneus (BA 19), left middle frontal gyrus (BA 11), left lingual gyrus (BA 18), right medial frontal gyrus (BA 11), bilateral inferior frontal gyrus (BA 47), left superior frontal gyrus (BA11), right cuneus (BA 19, 18), right superior temporal gyrus (BA 38), left subcallosal gyrus (BA 47), bilateral precuneus (BA 19), right medial frontal gyrus (BA 10), right superior frontal (BA 11), left cingulate gyrus (BA 32), left precentral gyrus (BA 6), and right fusiform gyrus (BA 19). These results suggest that acupuncture at the Taixi acupoint in elderly patients with mild cogni-tive impairment can also activate some brain regions.

  7. 氯胺酮对缺氧诱导胎鼠大脑皮层神经元特异性烯醇化酶的影响%Effects of ketamine on anoxia induced neurone specific enolase release from cerebral cortex neurons of fetal rats

    Institute of Scientific and Technical Information of China (English)

    王惠军; 薛玉良; 李兰英; 高春霖

    2011-01-01

    目的 探讨氯胺酮对神经元缺氧损伤的防护作用及机制.方法 应用无血清方法原代培养胎鼠大脑神经细胞,进行缺氧结合无糖处理,应用酶联免疫吸附试验测定缺氧前后细胞内外神经元特异性烯醇化酶(NSE)浓度,并应用逆转录聚合酶链反应观察缺氧前后细胞内NSE mRNA表达量的变化.结果 随着缺氧时间的延长,细胞外NSE浓度明显升高、细胞内降低(P<0.01),至缺氧5 h达高峰.缺氧1 h组缺氧前给予氯胺酮,随药物浓度的增加,细胞外NSE浓度逐渐降低[缺氧1 h组(4.95±0.41)μg/L,缺氧1 h+氯胺酮1μmol/L组(4.43±0.36)μg/L,缺氧I h+氯胺酮20 μmol/L组(3.53±0.46)μg/L,缺氧1 h+氯胺酮100 μmol/L组(3.17±0.23)μg/L]、细胞内逐渐升高[缺氧1 h组(22.0 ±0.76)μg/L,缺氧1 h+氯胺酮1 μmol/L组(24.7±0.84)μg/L,缺氧1 h+氯胺酮20μmoL/L组(28.8±0.91)μg/L,缺氧1 h+氯胺酮100 μmol/L(33.7±0.92)μg/L],呈剂量依赖性,氯胺酮100 μmol/L时接近对照组水平.随着缺氧时间延长,NSE mRNA相对表达量明显增高(对照组NSE相对表达量0.153±0.007,缺氧0.5 h组0.654±0.012.P<0.01),至1 h达高峰(NES相对表达量0.923±0.015);缺氧0.5 h组缺氧前给予患者不同浓度(1、20 μmol/L)氯胺酮后,NSE的表达量明显降低(NSE相对表达量分别为0.531±0.011、0.283±0.009,P<0.01).结论 氯胺酮可通过防止细胞膜的损伤,减少细胞内酶的外漏,并在基因表达和蛋白合成两个阶段对NSE进行调节,发挥对体外培养神经元缺氧性损伤的防护作用.%Objective To evaluate the effects of ketamine on neurone specific enolase (NSE) in combined oxygen-glucose deprivation of embryonic rat cortical neurons. Methods The mixed cell culture riching in neurons were deprived both oxygen and glucose. Using ELISA and RT-PCR method to assay the changes of intracellular and extracellular concentrations of NSE and the expression of NSE mRNA in hypoxic neurons treated with different

  8. Primary visual cortex volume and total neuron number are reduced in schizophrenia

    DEFF Research Database (Denmark)

    Dorph-Petersen, Karl-Anton; Pierri, Joseph H.; Wu, Qiang;

    2007-01-01

    with schizophrenia reported an increased density of neurons in the primary visual cortex (Brodmann's area 17, BA17). The observed changes in visual processing may thus be reflected in structural changes in the circuitry of BA17. To characterize the structural changes further we used stereological methods based...... on unbiased principles of sampling (Cavalieri's principle and the optical fractionator) to estimate the total volume and neuron number of BA17 in postmortem brains from 10 subjects with schizophrenia and 10 matched normal comparison subjects. In addition, we assessed cortical thickness. We found a marked...... and significant reduction in total neuron number (25%) and volume (22%) of BA17 in the schizophrenia group relative to the normal comparison subjects. In contrast, we found no changes in neuronal density or cortical thickness between the two groups. Subjects with schizophrenia therefore have a smaller cortical...

  9. Effects of transplantation with bone marrow-derived endothelial progenitor cells on learning, memory and neurons in the cortex of the parietal lobe after cerebral ischemia reperfusion injury of atherosclerotic model rats%内皮祖细胞移植对动脉粥样硬化模型大鼠脑缺血再灌注后学习记忆能力与脑顶叶皮质的影响

    Institute of Scientific and Technical Information of China (English)

    朱俊德; 王贵学; 余彦; 余资江; 肖朝伦; 王玉林

    2012-01-01

    目的 探讨内皮祖细胞(EPCs)移植对动脉粥样硬化(AS)模型大鼠脑缺血再灌注损伤(IRI)后学习记忆能力与脑顶叶皮质结构的影响.方法 高脂膳食饲养建立30只动脉粥样硬化大鼠模型,随机分为AS组,IRI组和EPCs移植组.采集骨髓分离EPCs并体外扩增培养,检测其表面标记物的表达;第7天采用线栓法制作局灶性IRI模型,建模成功后1d EPCs移植组经尾静脉移植EPCs,IRI组与AS组给予等量体积的磷酸盐缓冲液.移植后7d检测各组大鼠的行为能力、脑组织血管内皮生长因子(VEGF)含量及其mRNA表达与其结构的病理改变.结果 培养24h后见细胞贴壁生长逐渐变为梭形;第3天细胞明显增殖集落形成;第5天细胞集落逐渐增大呈现克隆样生长;第7天细胞汇合达80%;第10~14天细胞基本铺满瓶底呈铺路石样密集排列.荧光显微镜下,DIL-ac-LDL和FITC-UEA-1双荧光染色的细胞数占贴壁细胞数的75%以上.与IRI组相比,EPCs移植后大鼠的学习记忆能力较IRI组明显改善,VEGF含量及其mRNA表达显著下降(P<0.05).光镜下,EPCs移植组大鼠脑缺血侧顶叶皮质Caspase-3和胶质细胞原纤维酸性蛋白(GFAP)阳性神经元均较IRI组明显下降(P<0.05).结论 EPCs移植能改善AS模型大鼠脑IRI后的学习记忆能力、减轻脑组织的病理损害,这些变化提示EPCs促进了神经的修复.%Objective To study behavior abilities and morphological changes on neurons in the cortex of parietal lobe after cerebral ischemia reperfusion injury (IRI) of atherosclerotic ( AS) model rats and observe the effect of transplantation with bone marrow-derived endothelial progenitor cells (EPCs) on the AS model rat. Methods A total of thirty male adult Wister AS model rats were established by fat-rich diet feeding for six consecutive weeks. EPCs were obtained from the bone marrow and the cells cultured in vitro in M199. On the 7th day, middle cerebral artery occlusion (MCAO) rat models

  10. Effect of Transcranial Magnetic Stimulation on the Expression of c-Fos and Brain-derived Neurotrophic Factor of the Cerebral Cortex in Rats with Cerebral Infarct

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiaoqiao; MEI Yuanwu; LIU Chuanyu; YU Shanchun

    2007-01-01

    The effect of transcranial magnetic stimulation (TMS) on the neurological functional recovery and expression of c-Fos and brain-derived neurotrophic factor (BDNF) of the cerebral cortex in rats with cerebral infarction was investigated. Cerebral infarction models were established by using left middle cerebral artery occlusion (MCAO) and were randomly divided into a model group (n=40) and a TMS group (n=40). TMS treatment (2 times per day, 30 pulses per time) with a frequency of 0.5 Hz and magnetic field intensity of 1.33 Tesla was carried out in TMS group after MCAO. Modified neurological severity score (NSS) were recorded before and 1, 7, 14, 21, and 28 day(s) after MCAO. The expression of c-Fos and BDNF was immunohistochemically detected 1, 7,14, 21, and 28 day(s) after infarction respectively. Our results showed that a significant recovery of NSS (P<0.05) was found in animals treated by TMS on day 7, 14, 21, and 28 as compared with the animals in the model group. The positive expression of c-Fos and BDNF was detected in the cortex surrounding the infarction areas, while the expression of c-Fos and BDNF increased significantly in TMS treatment group in comparison with those in model group 7, 14, 21, and 28 days (P<0.05) and 7,14, 21 days (P<0.01) after infarction, respectively. It is concluded that TMS has therapeutic effect on cerebral infarction and this may have something to do with TMS's ability to promote the expression of c-Fos and BDNF of the cerebral cortex in rats with cerebral infarction.

  11. The origin of cortical neurons

    OpenAIRE

    Parnavelas J.G.

    2002-01-01

    Neurons of the mammalian cerebral cortex comprise two broad classes: pyramidal neurons, which project to distant targets, and the inhibitory nonpyramidal cells, the cortical interneurons. Pyramidal neurons are generated in the germinal ventricular zone, which lines the lateral ventricles, and migrate along the processes of radial glial cells to their positions in the developing cortex in an `inside-out' sequence. The GABA-containing nonpyramidal cells originate for the most part in the gangli...

  12. Development and Maturation of Embryonic Cortical Neurons Grafted into the Damaged Adult Motor Cortex

    Science.gov (United States)

    Ballout, Nissrine; Frappé, Isabelle; Péron, Sophie; Jaber, Mohamed; Zibara, Kazem; Gaillard, Afsaneh

    2016-01-01

    Injury to the human central nervous system can lead to devastating consequences due to its poor ability to self-repair. Neural transplantation aimed at replacing lost neurons and restore functional circuitry has proven to be a promising therapeutical avenue. We previously reported in adult rodent animal models with cortical lesions that grafted fetal cortical neurons could effectively re-establish specific patterns of projections and synapses. The current study was designed to provide a detailed characterization of the spatio-temporal in vivo development of fetal cortical transplanted cells within the lesioned adult motor cortex and their corresponding axonal projections. We show here that as early as 2 weeks after grafting, cortical neuroblasts transplanted into damaged adult motor cortex developed appropriate projections to cortical and subcortical targets. Grafted cells initially exhibited characteristics of immature neurons, which then differentiated into mature neurons with appropriate cortical phenotypes where most were glutamatergic and few were GABAergic. All cortical subtypes identified with the specific markers CTIP2, Cux1, FOXP2, and Tbr1 were generated after grafting as evidenced with BrdU co-labeling. The set of data provided here is of interest as it sets biological standards for future studies aimed at replacing fetal cells with embryonic stem cells as a source of cortical neurons. PMID:27536221

  13. Pathway-specific reorganization of projection neurons in somatosensory cortex during learning.

    Science.gov (United States)

    Chen, Jerry L; Margolis, David J; Stankov, Atanas; Sumanovski, Lazar T; Schneider, Bernard L; Helmchen, Fritjof

    2015-08-01

    In the mammalian brain, sensory cortices exhibit plasticity during task learning, but how this alters information transferred between connected cortical areas remains unknown. We found that divergent subpopulations of cortico-cortical neurons in mouse whisker primary somatosensory cortex (S1) undergo functional changes reflecting learned behavior. We chronically imaged activity of S1 neurons projecting to secondary somatosensory (S2) or primary motor (M1) cortex in mice learning a texture discrimination task. Mice adopted an active whisking strategy that enhanced texture-related whisker kinematics, correlating with task performance. M1-projecting neurons reliably encoded basic kinematics features, and an additional subset of touch-related neurons was recruited that persisted past training. The number of S2-projecting touch neurons remained constant, but improved their discrimination of trial types through reorganization while developing activity patterns capable of discriminating the animal's decision. We propose that learning-related changes in S1 enhance sensory representations in a pathway-specific manner, providing downstream areas with task-relevant information for behavior.

  14. Hyperlipidemia exacerbates cerebral injury through oxidative stress, inflammation and neuronal apoptosis in MCAO/reperfusion rats.

    Science.gov (United States)

    Cao, Xiao-Lu; Du, Jing; Zhang, Ying; Yan, Jing-Ting; Hu, Xia-Min

    2015-10-01

    stress, inflammation and neuronal apoptosis by coexistence of hyperlipidemia and cerebral I/R.

  15. Electro-cortical signs of early neuronal damage following transient global cerebral ischemia in rat

    DEFF Research Database (Denmark)

    Moldovan, M; Zagrean, Ana-Maria; Avramescu, S;

    2004-01-01

    During recovery after a transient global cerebral ischemia (TGCI), rat electrocorticogram (ECoG) shows epochs of synchronized activity (SA) alternating with epochs of low amplitude background activity (BA). The aim of this study was to compare the changes in these electrical activities during a 30...... did not change during reperfusion. Our data indicate that following cerebral ischemia the recovery of SA can take place independently of BA. The lack of recovery in BA may indicate early subcortical neuronal damage....

  16. Effect of electric acupuncture on the expression of NgR in the cerebral cortex,the medulla oblongata,and the spinal cord of hypertensive rats after cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    谭峰

    2014-01-01

    Objective To observe the effect of electric acupuncture(EA)on the Nogo receptors(NgR)protein expression in the cerebral cortex,the medulla oblongata,and the spinal cord of cerebral ischemia-reperfusion(I/R)stroke-prone renovascular hypertensive rats(RHRSP)with middle cerebral artery occlusion(MCAO)at different time points,and to investigate its possible mecha-

  17. Converging Neuronal Activity in Inferior Temporal Cortex during the Classification of Morphed Stimuli

    OpenAIRE

    Akrami, Athena; Liu, Yan; Treves, Alessandro; Jagadeesh, Bharathi

    2008-01-01

    How does the brain dynamically convert incoming sensory data into a representation useful for classification? Neurons in inferior temporal (IT) cortex are selective for complex visual stimuli, but their response dynamics during perceptual classification is not well understood. We studied IT dynamics in monkeys performing a classification task. The monkeys were shown visual stimuli that were morphed (interpolated) between pairs of familiar images. Their ability to classify the morphed images d...

  18. Nerve growth factor is primarily produced by GABAergic neurons of the adult rat cortex

    OpenAIRE

    Biane, Jeremy; Conner, James M.; Tuszynski, Mark H.

    2014-01-01

    Within the cortex, nerve growth factor (NGF) mediates the innervation of cholinergic neurons during development, maintains cholinergic corticopetal projections during adulthood and modulates cholinergic function through phenotypic control of the cholinergic gene locus. Recent studies suggest NGF may also play an important role in cortical plasticity in adulthood. Previously, NGF-producing cells have been shown to colocalize with GABAergic cell markers within the hippocampus, striatum, and bas...

  19. Exercise preconditioning exhibits neuroprotective effects on hippocampal CA1 neuronal damage after cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Nabi Shamsaei; Mehdi Khaksari; Sohaila Erfani; Hamid Rajabi; Nahid Aboutaleb

    2015-01-01

    Recent evidence has suggested the neuroprotective effects of physical exercise on cerebral isch-emic injury. However, the role of physical exercise in cerebral ischemia-induced hippocampal damage remains controversial. The aim of the present study was to evaluate the effects of pre-ischemia treadmill training on hippocampal CA1 neuronal damage after cerebral ischemia. Male adult rats were randomly divided into control, ischemia and exercise + ischemia groups. In the exercise + ischemia group, rats were subjected to running on a treadmill in a designated time schedule (5 days per week for 4 weeks). Then rats underwent cerebral ischemia induction th rough occlusion of common carotids followed by reperfusion. At 4 days after cerebral ischemia, rat learning and memory abilities were evaluated using passive avoidance memory test and rat hippocampal neuronal damage was detected using Nissl and TUNEL staining. Pre-ischemic ex-ercise signiifcantly reduced the number of TUNEL-positive cells and necrotic cell death in the hippocampal CA1 region as compared to the ischemia group. Moreover, pre-ischemic exercise significantly prevented ischemia-induced memory dysfunction. Pre-ischemic exercise mighct prevent memory deficits after cerebral ischemia through rescuing hippocampal CA1 neurons from ischemia-induced degeneration.

  20. [Diagnosis and prognosis of cerebral ischemic disturbances course using a method of artificial neuronal networks].

    Science.gov (United States)

    Ivanov, Iu S; Semin, G F

    2004-01-01

    Based on the data of examination of 224 patients with different stages of cerebral ischemic disturbances (CID) and 84 age-matched controls, an artificial neuronal network was constructed and tried in differential diagnosis of CID stages according to the data of transcranial ultrasonic dopplerography. Diagnostic efficacy of the network was 80% for sensitivity, 100% for specificity and 82.7% for reliability. A modeling of the influence of the main risk factors for cerebral ischemia and of the reserve state of cerebral hemodynamics for establishing the stage of CID was performed.

  1. DEVELOPMENTAL HYPOTHYROIDISM REDUCES PARVALBUMIN EXPRESSION IN GABAERGIC NEURONS OF CORTEX AND HIPPOCAMPUS: IMMUNOHISTOCHEMICAL FINDINGS AND FUNCTIONAL CORRELATES.

    Science.gov (United States)

    GABAergic interneurons comprise the bulk of local inhibitory neuronal circuitry in cortex and hippocampus and a subpopulation of these interneurons contain the calcium binding protein, parvalbumin (PV). A previous report indicated that severe hypothyroidism reduced PV immunoreact...

  2. Magnetic stimulation at Neiguan (PC6) acupoint increases connections between cerebral cortex regions

    Institute of Scientific and Technical Information of China (English)

    Hong-li Yu; Gui-zhi Xu; Lei Guo; Ling-di Fu; Shuo Yang; Shuo Shi; Hua Lv

    2016-01-01

    Stimulation at speciifc acupoints can activate cortical regions in human subjects. Previous studies have mainly focused on a single brain region. However, the brain is a network and many brain regions participate in the same task. The study of a single brain region alone cannot clearly explain any brain-related issues. Therefore, for the present study, magnetic stimulation was used to stimulate the Neiguan (PC6) acu-point, and 32-channel electroencephalography data were recorded before and after stimulation. Brain functional networks were constructed based on electroencephalography data to determine the relationship between magnetic stimulation at the PC6 acupoint and cortical excitabil-ity. Results indicated that magnetic stimulation at the PC6 acupoint increased connections between cerebral cortex regions.

  3. MRI in chronic toluene abuse: low signal in the cerebral cortex on T2-weighted images

    International Nuclear Information System (INIS)

    MRI may be helpful in showing brain toxicity associated with chronic toluene inhalation. We report clinical and MRI findings over 3 years in a man with gradual neurologic decline secondary to toluene abuse. Cerebral atrophy most prominently involved the corpus callosum and cerebellar vermis. On T2-weighted images, loss of gray-white matter contrast, diffuse supratentorial white matter high-signal lesions, and low signal in the basal ganglia and midbrain were seen. In addition, MRI showed abnormal labor cortical low signal on T2-weighted images, most prominent in the primary motor and visual cortex. This cortical T2 shortening, not previously described in this condition, may reflect iron deposition. (orig.)

  4. The subcellular distribution and properties of hexokinases in the guinea-pig cerebral cortex.

    Science.gov (United States)

    Bachelard, H S

    1967-07-01

    1. Hexokinase activities were estimated in primary subcellular fractions from guinea-pig cerebral cortex and in sucrose-density-gradient subfractions of the mitochondrial and microsomal fractions. 2. Appreciable activities were observed in mitochondrial, microsomal and soluble fractions. The activity in the mitochondrial fraction was associated with the mitochondria rather than with myelin or nerve endings and that in the microsomal fraction was associated with membrane fragments. 3. Most of the mitochondrial activity was extracted in soluble form by osmotic ;shock'. The activity of the mitochondrial extract differed from the soluble activity in kinetic properties and in electrophoretic behaviour. 4. No evidence was obtained for the presence of a high-K(m) glucokinase in the brain. 5. The results are discussed in terms of relevance to considerations of glucose utilization by the brain.

  5. Adaptation in the visual cortex: influence of membrane trajectory and neuronal firing pattern on slow afterpotentials.

    Directory of Open Access Journals (Sweden)

    Vanessa F Descalzo

    Full Text Available The input/output relationship in primary visual cortex neurons is influenced by the history of the preceding activity. To understand the impact that membrane potential trajectory and firing pattern has on the activation of slow conductances in cortical neurons we compared the afterpotentials that followed responses to different stimuli evoking similar numbers of action potentials. In particular, we compared afterpotentials following the intracellular injection of either square or sinusoidal currents lasting 20 seconds. Both stimuli were intracellular surrogates of different neuronal responses to prolonged visual stimulation. Recordings from 99 neurons in slices of visual cortex revealed that for stimuli evoking an equivalent number of spikes, sinusoidal current injection activated a slow afterhyperpolarization of significantly larger amplitude (8.5 ± 3.3 mV and duration (33 ± 17 s than that evoked by a square pulse (6.4 ± 3.7 mV, 28 ± 17 s; p<0.05. Spike frequency adaptation had a faster time course and was larger during plateau (square pulse than during intermittent (sinusoidal depolarizations. Similar results were obtained in 17 neurons intracellularly recorded from the visual cortex in vivo. The differences in the afterpotentials evoked with both protocols were abolished by removing calcium from the extracellular medium or by application of the L-type calcium channel blocker nifedipine, suggesting that the activation of a calcium-dependent current is at the base of this afterpotential difference. These findings suggest that not only the spikes, but the membrane potential values and firing patterns evoked by a particular stimulation protocol determine the responses to any subsequent incoming input in a time window that spans for tens of seconds to even minutes.

  6. Differential regulation of microtubule severing by APC underlies distinct patterns of projection neuron and interneuron migration

    OpenAIRE

    Eom, Tae-Yeon; Stanco, Amelia; Guo, Jiami; Wilkins, Gary; Deslauriers, Danielle; Yan, Jessica; Monckton, Chase; Blair, Josh; Oon, Eesim; Perez, Abby; Salas, Eduardo; Oh, Adrianna; Ghukasyan, Vladimir; Snider, William D; John L R Rubenstein

    2014-01-01

    Coordinated migration of distinct classes of neurons to appropriate positions leads to the formation of functional neuronal circuitry in the cerebral cortex. Two major classes of cortical neurons, interneurons and projection neurons, utilize distinctly different modes (radial vs. tangential) and routes of migration to arrive at their final positions in the cerebral cortex. Here, we show that adenomatous polyposis coli (APC) modulates microtubule (MT) severing in interneurons to facilitate tan...

  7. Computerized method for automated measurement of thickness of cerebral cortex for 3-D MR images

    Science.gov (United States)

    Arimura, Hidetaka; Yoshiura, Takashi; Kumazawa, Seiji; Koga, Hiroshi; Sakai, Shuji; Mihara, Futoshi; Honda, Hiroshi; Ohki, Masafumi; Toyofuku, Fukai; Higashida, Yoshiharu

    2006-03-01

    Alzheimer's disease (AD) is associated with the degeneration of cerebral cortex, which results in focal volume change or thinning in the cerebral cortex in magnetic resonance imaging (MRI). Therefore, the measurement of the cortical thickness is important for detection of the atrophy related to AD. Our purpose was to develop a computerized method for automated measurement of the cortical thickness for three-dimensional (3-D) MRI. The cortical thickness was measured with normal vectors from white matter surface to cortical gray matter surface on a voxel-by-voxel basis. First, a head region was segmented by use of an automatic thresholding technique, and then the head region was separated into the cranium region and brain region by means of a multiple gray level thresholding with monitoring the ratio of the first maximum volume to the second one. Next, a fine white matter region was determined based on a level set method as a seed region of the rough white matter region extracted from the brain region. Finally, the cortical thickness was measured by extending normal vectors from the white matter surface to gray matter surface (brain surface) on a voxel-by-voxel basis. We applied the computerized method to high-resolution 3-D T1-weighted images of the whole brains from 7 clinically diagnosed AD patients and 8 healthy subjects. The average cortical thicknesses in the upper slices for AD patients were thinner than those for non-AD subjects, whereas the average cortical thicknesses in the lower slices for most AD patients were slightly thinner. Our preliminary results suggest that the MRI-based computerized measurement of gray matter atrophy is promising for detecting AD.

  8. Effects of Cerebral Ischemia in Mice Deficient in Neuronal Nitric Oxide Synthase

    Science.gov (United States)

    Huang, Zhihong; Huang, Paul L.; Panahian, Nariman; Dalkara, Turgay; Fishman, Mark C.; Moskowitz, Michael A.

    1994-09-01

    The proposal that nitric oxide (NO) or its reactant products mediate toxicity in brain remains controversial in part because of the use of nonselective agents that block NO formation in neuronal, glial, and vascular compartments. In mutant mice deficient in neuronal NO synthase (NOS) activity, infarct volumes decreased significantly 24 and 72 hours after middle cerebral artery occlusion, and the neurological deficits were less than those in normal mice. This result could not be accounted for by differences in blood flow or vascular anatomy. However, infarct size in the mutant became larger after endothelial NOS inhibition by nitro-L-arginine administration. Hence, neuronal NO production appears to exacerbate acute ischemic injury, whereas vascular NO protects after middle cerebral artery occlusion. The data emphasize the importance of developing selective inhibitors of the neuronal isoform.

  9. Projection neurons in the cortex and hippocampus: differential effects of chronic khat and ethanol exposure in adult male rats

    Science.gov (United States)

    Alele, Paul E; Matovu, Daniel; Imanirampa, Lawrence; Ajayi, Abayomi M; Kasule, Gyaviira T

    2016-01-01

    Background Recent evidence suggests that many individuals who chew khat recreationally also drink ethanol to offset the stimulating effect of khat. The objective of this study was to describe the separate and interactive effects of chronic ethanol and khat exposure on key projection neurons in the cortex and hippocampus of young adult male rats. Methods Young adult male Sprague Dawley rats were divided into six treatment groups: 2 g/kg khat, 4 g/kg khat, 4 g/kg ethanol, combined khat and ethanol (4 g/kg each), a normal saline control, and an untreated group. Treatments were administered orally for 28 continuous days; brains were then harvested, sectioned, and routine hematoxylin–eosin staining was done. Following photomicrography, ImageJ® software captured data regarding neuron number and size. Results No differences occurred in counts of both granular and pyramidal projection neurons in the motor cortex and all four subfields of the hippocampal formation. Khat dose-dependently increased pyramidal neuron size in the motor cortex and the CA3 region, but had different effects on granular neuron size in the dentate gyrus and the motor cortex. Mean pyramidal neuron size for the ethanol-only treatment was larger than that for the 2 g/kg khat group, and the saline control group, in CA3 and in the motor cortex. Concomitant khat and ethanol increased granular neuron size in the motor cortex, compared to the 2 g/kg khat group, the 4 g/kg khat group, and the 4 g/kg ethanol group. In the CA3 region, the 4 g/kg ethanol group showed a larger mean pyramidal neuron size than the combined khat and ethanol group. Conclusion These results suggest that concomitant khat and ethanol exposure changes granular and pyramidal projection neuron sizes differentially in the motor cortex and hippocampus, compared to the effects of chronic exposure to these two drugs separately.

  10. Oxidative metabolic activity of cerebral cortex after fluid-percussion head injury in the cat.

    Science.gov (United States)

    Duckrow, R B; LaManna, J C; Rosenthal, M; Levasseur, J E; Patterson, J L

    1981-05-01

    To assess the metabolic and vascular effects of head trauma, fluid-percussion pressure waves were transmitted to the brains of anesthetized, paralyzed, and artificially ventilated cats. Changes in the redox state of cytochrome a,a3, and relative local blood volume were measured in situ by dual-wavelength reflection spectrophotometry of the cortical surface viewed through an acrylic cranial window implanted within the closed skull. Initial fluid-percussion impacts of 0.5 to 2.8 atm peak pressure produced consistent transient oxidation of cytochrome a,a3 and increases of cortical blood volume. These changes occurred despite the presence of transient posttraumatic hypotension i some cases. Also, impact-induced alterations of vascular tone occurred, independent of the presence or absence of transient hypertension in the posttraumatic period. These data demonstrate that hypoxia does not play a role in the immediate posttraumatic period in cerebral cortex, and are consistent with the idea that after injury there is increased cortical energy conservation. These data also support the concept that head trauma alters the relationship of metabolism and cerebral circulation in the period immediately after injury. PMID:7229699

  11. A radial glia-specific role of RhoA in double cortex formation

    DEFF Research Database (Denmark)

    Cappello, Silvia; Böhringer, Christian R J; Bergami, Matteo;

    2012-01-01

    The positioning of neurons in the cerebral cortex is of crucial importance for its function as highlighted by the severe consequences of migrational disorders in patients. Here we show that genetic deletion of the small GTPase RhoA in the developing cerebral cortex results in two migrational diso...

  12. Prenatal Nicotine Exposure Impairs the Proliferation of Neuronal Progenitors, Leading to Fewer Glutamatergic Neurons in the Medial Prefrontal Cortex.

    Science.gov (United States)

    Aoyama, Yuki; Toriumi, Kazuya; Mouri, Akihiro; Hattori, Tomoya; Ueda, Eriko; Shimato, Akane; Sakakibara, Nami; Soh, Yuka; Mamiya, Takayoshi; Nagai, Taku; Kim, Hyoung-Chun; Hiramatsu, Masayuki; Nabeshima, Toshitaka; Yamada, Kiyofumi

    2016-01-01

    Cigarette smoking during pregnancy is associated with various disabilities in the offspring such as attention deficit/hyperactivity disorder, learning disabilities, and persistent anxiety. We have reported that nicotine exposure in female mice during pregnancy, in particular from embryonic day 14 (E14) to postnatal day 0 (P0), induces long-lasting behavioral deficits in offspring. However, the mechanism by which prenatal nicotine exposure (PNE) affects neurodevelopment, resulting in behavioral deficits, has remained unclear. Here, we report that PNE disrupted the proliferation of neuronal progenitors, leading to a decrease in the progenitor pool in the ventricular and subventricular zones. In addition, using a cumulative 5-bromo-2'-deoxyuridine labeling assay, we evaluated the rate of cell cycle progression causing the impairment of neuronal progenitor proliferation, and uncovered anomalous cell cycle kinetics in mice with PNE. Accordingly, the density of glutamatergic neurons in the medial prefrontal cortex (medial PFC) was reduced, implying glutamatergic dysregulation. Mice with PNE exhibited behavioral impairments in attentional function and behavioral flexibility in adulthood, and the deficits were ameliorated by microinjection of D-cycloserine into the PFC. Collectively, our findings suggest that PNE affects the proliferation and maturation of progenitor cells to glutamatergic neuron during neurodevelopment in the medial PFC, which may be associated with cognitive deficits in the offspring. PMID:26105135

  13. Stage-specific requirement for cyclin D1 in glial progenitor cells of the cerebral cortex.

    Science.gov (United States)

    Nobs, Lionel; Baranek, Constanze; Nestel, Sigrun; Kulik, Akos; Kapfhammer, Josef; Nitsch, Cordula; Atanasoski, Suzana

    2014-05-01

    Despite the vast abundance of glial progenitor cells in the mouse brain parenchyma, little is known about the molecular mechanisms driving their proliferation in the adult. Here we unravel a critical role of the G1 cell cycle regulator cyclin D1 in controlling cell division of glial cells in the cortical grey matter. We detect cyclin D1 expression in Olig2-immunopositive (Olig2+) oligodendrocyte progenitor cells, as well as in Iba1+ microglia and S100β+ astrocytes in cortices of 3-month-old mice. Analysis of cyclin D1-deficient mice reveals a cell and stage-specific molecular control of cell cycle progression in the various glial lineages. While proliferation of fast dividing Olig2+ cells at early postnatal stages becomes gradually dependent on cyclin D1, this particular G1 regulator is strictly required for the slow divisions of Olig2+/NG2+ oligodendrocyte progenitors in the adult cerebral cortex. Further, we find that the population of mature oligodendrocytes is markedly reduced in the absence of cyclin D1, leading to a significant decrease in the number of myelinated axons in both the prefrontal cortex and the corpus callosum of 8-month-old mutant mice. In contrast, the pool of Iba1+ cells is diminished already at postnatal day 3 in the absence of cyclin D1, while the number of S100β+ astrocytes remains unchanged in the mutant.

  14. Promotion of proliferation in the developing cerebral cortex by EphA4 forward signaling

    Science.gov (United States)

    North, Hilary A.; Zhao, Xiumei; Kolk, Sharon M.; Clifford, Meredith A.; Ziskind, Daniela M.; Donoghue, Maria J.

    2009-01-01

    Summary Eph receptors are widely expressed during cerebral cortical development, yet a role for Eph signaling in the generation of cells during corticogenesis has not been shown. Cortical progenitor cells selectively express one receptor, EphA4, and reducing EphA4 signaling in cultured progenitors suppressed proliferation, decreasing cell number. In vivo, EphA4-/- cortex had a reduced area, fewer cells and less cell division compared with control cortex. To understand the effects of EphA4 signaling in corticogenesis, EphA4-mediated signaling was selectively depressed or elevated in cortical progenitors in vivo. Compared with control cells, cells with reduced EphA4 signaling were rare and mitotically inactive. Conversely, overexpression of EphA4 maintained cells in their progenitor states at the expense of subsequent maturation, enlarging the progenitor pool. These results support a role for EphA4 in the autonomous promotion of cell proliferation during corticogenesis. Although most ephrins were undetectable in cortical progenitors, ephrin B1 was highly expressed. Our analyses demonstrate that EphA4 and ephrin B1 bind to each other, thereby initiating signaling. Furthermore, overexpression of ephrin B1 stimulated cell division of neighboring cells, supporting the hypothesis that ephrin B1-initiated forward signaling of EphA4 promotes cortical cell division. PMID:19542359

  15. Numeric and symbolic knowledge representation of cerebral cortex anatomy: methods and preliminary results.

    Science.gov (United States)

    Dameron, O; Gibaud, B; Morandi, X

    2004-06-01

    The human cerebral cortex anatomy describes the brain organization at the scale of gyri and sulci. It is used as landmarks for neurosurgery as well as localization support for functional data analysis or inter-subject data comparison. Existing models of the cortex anatomy either rely on image labeling but fail to represent variability and structural properties or rely on a conceptual model but miss the inner 3D nature and relations of anatomical structures. This study was therefore conducted to propose a model of sulco-gyral anatomy for the healthy human brain. We hypothesized that both numeric knowledge (i.e., image-based) and symbolic knowledge (i.e., concept-based) have to be represented and coordinated. In addition, the representation of this knowledge should be application-independent in order to be usable in various contexts. Therefore, we devised a symbolic model describing specialization, composition and spatial organization of cortical anatomical structures. We also collected numeric knowledge such as 3D models of shape and shape variation about cortical anatomical structures. For each numeric piece of knowledge, a companion file describes the concept it refers to and the nature of the relationship. Demonstration software performs a mapping between the numeric and the symbolic aspects for browsing the knowledge base. PMID:15118839

  16. Developmental stability of taurine's activation on glycine receptors in cultured neurons of rat auditory cortex.

    Science.gov (United States)

    Tang, Zheng-Quan; Lu, Yun-Gang; Chen, Lin

    2008-01-01

    Taurine is an endogenous amino acid that can activate glycine and/or gamma-aminobutyric acid type A (GABA(A)) receptors in the central nervous system. During natural development, taurine's receptor target undergoes a shift from glycine receptors to GABA(A) receptors in cortical neurons. Here, we demonstrate that taurine's receptor target in cortical neurons remains stable during in vitro development. With whole-cell patch-clamp recordings, we found that taurine always activated glycine receptors, rather than GABA(A) receptors, in neurons of rat auditory cortex cultured for 5-22 days. Our results suggest that the functional sensitivity of glycine and GABA(A) receptors to taurine is critically regulated by their developmental environments.

  17. Corticospinal neurons in macaque ventral premotor cortex with mirror properties: a potential mechanism for action suppression?

    Science.gov (United States)

    Kraskov, Alexander; Dancause, Numa; Quallo, Marsha M; Shepherd, Samantha; Lemon, Roger N

    2009-12-24

    The discovery of "mirror neurons" in area F5 of the ventral premotor cortex has prompted many theories as to their possible function. However, the identity of mirror neurons remains unknown. Here, we investigated whether identified pyramidal tract neurons (PTNs) in area F5 of two adult macaques exhibited "mirror-like" activity. About half of the 64 PTNs tested showed significant modulation of their activity while monkeys observed precision grip of an object carried out by an experimenter, with somewhat fewer showing modulation during precision grip without an object or grasping concealed from the monkey. Therefore, mirror-like activity can be transmitted directly to the spinal cord via PTNs. A novel finding is that many PTNs (17/64) showed complete suppression of discharge during action observation, while firing actively when the monkey grasped food rewards. We speculate that this suppression of PTN discharge might be involved in the inhibition of self-movement during action observation.

  18. Activity of Somatosensory-Responsive Neurons in High Subdivisions of SI Cortex during Locomotion

    Science.gov (United States)

    Favorov, Oleg V.; Nilaweera, Wijitha U.; Miasnikov, Alexandre A.

    2015-01-01

    Responses of neurons in the primary somatosensory cortex during movements are poorly understood, even during such simple tasks as walking on a flat surface. In this study, we analyzed spike discharges of neurons in the rostral bank of the ansate sulcus (areas 1–2) in 2 cats while the cats walked on a flat surface or on a horizontal ladder, a complex task requiring accurate stepping. All neurons (n = 82) that had receptive fields (RFs) on the contralateral forelimb exhibited frequency modulation of their activity that was phase locked to the stride cycle during simple locomotion. Neurons with proximal RFs (upper arm/shoulder) and pyramidal tract-projecting neurons (PTNs) with fast-conducting axons tended to fire at peak rates in the middle of the swing phase, whereas neurons with RFs on the distal limb (wrist/paw) and slow-conducting PTNs typically showed peak firing at the transition between swing and stance phases. Eleven of 12 neurons with tactile RFs on the volar forepaw began firing toward the end of swing, with peak activity occurring at the moment of foot contact with floor, thereby preceding the evoked sensory volley from touch receptors. Requirement to step accurately on the ladder affected 91% of the neurons, suggesting their involvement in control of accuracy of stepping. During both tasks, neurons exhibited a wide variety of spike distributions within the stride cycle, suggesting that, during either simple or ladder locomotion, they represent the cycling somatosensory events in their activity both predictively before and reflectively after these events take place. PMID:25995465

  19. Neuronal categorization and discrimination of social behaviors in primate prefrontal cortex.

    Directory of Open Access Journals (Sweden)

    Joji Tsunada

    Full Text Available It has been implied that primates have an ability to categorize social behaviors between other individuals for the execution of adequate social-interactions. Since the lateral prefrontal cortex (LPFC is involved in both the categorization and the processing of social information, the primate LPFC may be involved in the categorization of social behaviors. To test this hypothesis, we examined neuronal activity in the LPFC of monkeys during presentations of two types of movies of social behaviors (grooming, mounting and movies of plural monkeys without any eye- or body-contacts between them (no-contacts movies. Although the monkeys were not required to categorize and discriminate the movies in this task, a subset of neurons sampled from the LPFC showed a significantly different activity during the presentation of a specific type of social behaviors in comparison with the others. These neurons categorized social behaviors at the population level and, at the individual neuron level, the majority of the neurons discriminated each movie within the same category of social behaviors. Our findings suggest that a fraction of LPFC neurons process categorical and discriminative information of social behaviors, thereby contributing to the adaptation to social environments.

  20. Avalanche Analysis from Multielectrode Ensemble Recordings in Cat, Monkey, and Human Cerebral Cortex during Wakefulness and Sleep

    OpenAIRE

    Nima eDehghani; Hatsopoulos, Nicholas G.; Haga, Zach D.; Rebecca eParker; Bradley eGreger; Eric eHalgren; Sydney S Cash; Alain eDestexhe

    2012-01-01

    Self-organized critical states are found in many natural systems, from earthquakes to forest fires, they have also been observed in neural systems, particularly, in neuronal cultures. However, the presence of critical states in the awake brain remains controversial. Here, we compared avalanche analyses performed on different in vivo preparations during wakefulness, slow-wave sleep, and REM sleep, using high density electrode arrays in cat motor cortex (96 electrodes), monkey motor cortex and ...

  1. How neurons migrate: a dynamic in-silico model of neuronal migration in the developing cortex

    LENUS (Irish Health Repository)

    Setty, Yaki

    2011-09-30

    Abstract Background Neuronal migration, the process by which neurons migrate from their place of origin to their final position in the brain, is a central process for normal brain development and function. Advances in experimental techniques have revealed much about many of the molecular components involved in this process. Notwithstanding these advances, how the molecular machinery works together to govern the migration process has yet to be fully understood. Here we present a computational model of neuronal migration, in which four key molecular entities, Lis1, DCX, Reelin and GABA, form a molecular program that mediates the migration process. Results The model simulated the dynamic migration process, consistent with in-vivo observations of morphological, cellular and population-level phenomena. Specifically, the model reproduced migration phases, cellular dynamics and population distributions that concur with experimental observations in normal neuronal development. We tested the model under reduced activity of Lis1 and DCX and found an aberrant development similar to observations in Lis1 and DCX silencing expression experiments. Analysis of the model gave rise to unforeseen insights that could guide future experimental study. Specifically: (1) the model revealed the possibility that under conditions of Lis1 reduced expression, neurons experience an oscillatory neuron-glial association prior to the multipolar stage; and (2) we hypothesized that observed morphology variations in rats and mice may be explained by a single difference in the way that Lis1 and DCX stimulate bipolar motility. From this we make the following predictions: (1) under reduced Lis1 and enhanced DCX expression, we predict a reduced bipolar migration in rats, and (2) under enhanced DCX expression in mice we predict a normal or a higher bipolar migration. Conclusions We present here a system-wide computational model of neuronal migration that integrates theory and data within a precise

  2. Developmental patterns of doublecortin expression and white matter neuron density in the postnatal primate prefrontal cortex and schizophrenia.

    Directory of Open Access Journals (Sweden)

    Samantha J Fung

    Full Text Available Postnatal neurogenesis occurs in the subventricular zone and dentate gyrus, and evidence suggests that new neurons may be present in additional regions of the mature primate brain, including the prefrontal cortex (PFC. Addition of new neurons to the PFC implies local generation of neurons or migration from areas such as the subventricular zone. We examined the putative contribution of new, migrating neurons to postnatal cortical development by determining the density of neurons in white matter subjacent to the cortex and measuring expression of doublecortin (DCX, a microtubule-associated protein involved in neuronal migration, in humans and rhesus macaques. We found a striking decline in DCX expression (human and macaque and density of white matter neurons (humans during infancy, consistent with the arrival of new neurons in the early postnatal cortex. Considering the expansion of the brain during this time, the decline in white matter neuron density does not necessarily indicate reduced total numbers of white matter neurons in early postnatal life. Furthermore, numerous cells in the white matter and deep grey matter were positive for the migration-associated glycoprotein polysialiated-neuronal cell adhesion molecule and GAD65/67, suggesting that immature migrating neurons in the adult may be GABAergic. We also examined DCX mRNA in the PFC of adult schizophrenia patients (n = 37 and matched controls (n = 37 and did not find any difference in DCX mRNA expression. However, we report a negative correlation between DCX mRNA expression and white matter neuron density in adult schizophrenia patients, in contrast to a positive correlation in human development where DCX mRNA and white matter neuron density are higher earlier in life. Accumulation of neurons in the white matter in schizophrenia would be congruent with a negative correlation between DCX mRNA and white matter neuron density and support the hypothesis of a migration deficit in

  3. Effects of percutaneous midband pulse current stimulation in hepatic region on free radical and nissl bodies in cerebral cortex of rats with exercise-induced fatigue

    Directory of Open Access Journals (Sweden)

    Jia ZHANG

    2015-06-01

    Full Text Available Objective To investigate the effects of percutaneous midband pulse current stimulation in hepatic region on anti-exercise fatigue ability and the free radicals and nissl bodies in cerebral cortex tissue of rats with exercise-induced fatigue. Methods Seventy-two 8-week old male Wistar rats were randomly divided into 4 groups (18 each: control group (CG, fatigue group (FG, stimulation before fatigue group (SBF and stimulation after fatigue group (SAF. Animals in FG, SBF and SAF group were used to reproduce the swimming-exhaustion models. Midband current stimulation (1024Hz, 10mA, current cycle 1sec for 20 minutes was given to the rats of group SBF before swimming, and to those in group SAF after exhaustion. At the weekend of the 1st, 3rd and 5th week after modeling, the exhaustive swimming time of rats in all but CG group was observed. Cerebral cortex tissue was harvested for the estimation of the level of lipid peroxidation, including SOD, MDA, GSH-Px and SOD/MDA, and the histopathological changes in nissl bodies in neurons were observed. Results At the 1st weekend after modeling, no significant difference was found in all the indexes among the 4 groups, while at the 3rd weekend, the exhaustive time was obviously longer in SAF group than in FG group, and also in SAF group than in FG and SBF group at the 5th weekend (P<0.05. At the 5th weekend, the SOD and GSH-Px levels and SOD/MDA contents were obviously lower in FG and SBF group than in CG and SAF group, and the MDA content was obviously higher in FG and SBF group than in CG and SAF group (P<0.05. As regarding the nissl bodies in neurons, it is observed that the ratio of number/area was obviously higher in SAF group than in FG and SBF group at the 5th weekend (P<0.01. Conclusion Percutaneous stimulation of hepatic region with midband pulse current can effectively reduce the lipid peroxidation damage of cerebral cortex tissue and decrease the dissolution and loss of nissl bodies in

  4. KATP channels modulate intrinsic firing activity of immature entorhinal cortex layer III neurons

    Directory of Open Access Journals (Sweden)

    Maria S. Lemak

    2014-08-01

    Full Text Available Medial temporal lobe structures are essential for memory formation which is associated with coherent network oscillations. During ontogenesis, these highly organized patterns develop from distinct, less synchronized forms of network activity. This maturation process goes along with marked changes in intrinsic firing patterns of individual neurons. One critical factor determining neuronal excitability is activity of ATP-sensitive K+ channels (KATP channels which coupled electrical activity to metabolic state. Here, we examined the role of KATP channels for intrinsic firing patterns and emerging network activity in the immature medial entorhinal cortex (mEC of rats. Western blot analysis of Kir6.2 (a subunit of the KATP channel confirmed expression of this protein in the immature entorhinal cortex. Neuronal activity was monitored by field potential (fp and whole-cell recordings from layer III of the mEC in horizontal brain slices obtained at postnatal day (P 6-13. Spontaneous fp-bursts were suppressed by the KATP channel opener diazoxide and prolonged after blockade of KATP channels by glibenclamide. Immature mEC LIII principal neurons displayed two dominant intrinsic firing patterns, prolonged bursts or regular firing activity, respectively. Burst discharges were suppressed by the KATP channel openers diazoxide and NN414, and enhanced by the KATP channel blockers tolbutamide and glibenclamide. Activity of regularly firing neurons was modulated in a frequency-dependent manner: the diazoxide-mediated reduction of firing correlated negatively with basal frequency, while the tolbutamide-mediated increase of firing showed a positive correlation. These data are in line with an activity-dependent regulation of KATP channel activity. Together, KATP channels exert powerful modulation of intrinsic firing patterns and network activity in the immature mEC.

  5. Three counting methods agree on cell and neuron number in chimpanzee primary visual cortex

    Directory of Open Access Journals (Sweden)

    Daniel James Miller

    2014-05-01

    Full Text Available Determining the cellular composition of specific brain regions is crucial to our understanding of the function of neurobiological systems. It is therefore useful to identify the extent to which different methods agree when estimating the same properties of brain circuitry. In this study, we estimated the number of neuronal and non-neuronal cells in the primary visual cortex (area 17 or V1 of both hemispheres from a single chimpanzee. Specifically, we processed samples distributed across V1 of the right hemisphere after cortex was flattened into a sheet using two variations of the isotropic fractionator cell and neuron counting method. We processed the left hemisphere as serial brain slices for stereological investigation. The goal of this study was to evaluate the agreement between these methods in the most direct manner possible by comparing estimates of cell density across one brain region of interest in a single individual. In our hands, these methods produced similar estimates of the total cellular population (approximately 1 billion as well as the number of neurons (approximately 675 million in chimpanzee V1, providing evidence that both techniques estimate the same parameters of interest. In addition, our results indicate the strengths of each distinct tissue preparation procedure, highlighting the importance of attention to anatomical detail. In summary, we found that the isotropic fractionator and the stereological optical fractionator produced concordant estimates of the cellular composition of V1, and that this result supports the conclusion that chimpanzees conform to the primate pattern of exceptionally high packing density in V1. Ultimately, our data suggest that investigators can optimize their experimental approach by using any of these counting methods to obtain reliable cell and neuron counts.

  6. Effects of low dose x-ray on development and differentiation of cerebral cortex, 13. Observation of construction of cerebral cortex in mice irradiated at 17 days of gestational age

    Energy Technology Data Exchange (ETDEWEB)

    Hoshino, K.; Hayashi, Y.; Ito, Y.; Kameyama, Y. (Nagoya Univ. (Japan). Research Inst. of Environmental Medicine)

    1980-03-01

    ICR mice were irradiated with 25 or 100 R of x-ray at 17 days of pregnancy, and /sup 3/H-thymidine was injected immediately after the irradiation. The brain of progenies which were born from irradiated ICR mice was extracted 4 weeks after their birth, and histoautoradiography of the cerebram were made. Distribution of nerve cells labelled strongly with /sup 3/H-thymidine was observed, and the construction of cerebral cortex was discussed. Abnormality in parietal region of new cerebral cortex in which nerve cells labelled strongly with /sup 3/H-thymidine distributed was not found, but a count of nerve cells distributing tended to decrease according to exposure dose.

  7. Learning alters theta amplitude, theta-gamma coupling and neuronal synchronization in inferotemporal cortex

    Directory of Open Access Journals (Sweden)

    Nicol Alister U

    2011-06-01

    Full Text Available Abstract Background How oscillatory brain rhythms alone, or in combination, influence cortical information processing to support learning has yet to be fully established. Local field potential and multi-unit neuronal activity recordings were made from 64-electrode arrays in the inferotemporal cortex of conscious sheep during and after visual discrimination learning of face or object pairs. A neural network model has been developed to simulate and aid functional interpretation of learning-evoked changes. Results Following learning the amplitude of theta (4-8 Hz, but not gamma (30-70 Hz oscillations was increased, as was the ratio of theta to gamma. Over 75% of electrodes showed significant coupling between theta phase and gamma amplitude (theta-nested gamma. The strength of this coupling was also increased following learning and this was not simply a consequence of increased theta amplitude. Actual discrimination performance was significantly correlated with theta and theta-gamma coupling changes. Neuronal activity was phase-locked with theta but learning had no effect on firing rates or the magnitude or latencies of visual evoked potentials during stimuli. The neural network model developed showed that a combination of fast and slow inhibitory interneurons could generate theta-nested gamma. By increasing N-methyl-D-aspartate receptor sensitivity in the model similar changes were produced as in inferotemporal cortex after learning. The model showed that these changes could potentiate the firing of downstream neurons by a temporal desynchronization of excitatory neuron output without increasing the firing frequencies of the latter. This desynchronization effect was confirmed in IT neuronal activity following learning and its magnitude was correlated with discrimination performance. Conclusions Face discrimination learning produces significant increases in both theta amplitude and the strength of theta-gamma coupling in the inferotemporal cortex

  8. Effects of Vision Restoration Training on Early Visual Cortex in Patients With Cerebral Blindness Investigated With Functional Magnetic Resonance Imaging

    NARCIS (Netherlands)

    Raemaekers, M.; Bergsma, D.P.; Wezel, van R.J.A.; Wildt, van der G.J.; Berg, van den A.V.

    2011-01-01

    Cerebral blindness is a loss of vision as a result of postchiasmatic damage to the visual pathways. Parts of the lost visual field can be restored through training. However, the neuronal mechanisms through which training effects occur are still unclear. We therefore assessed training-induced changes

  9. Predicting spike occurrence and neuronal responsiveness from LFPs in primary somatosensory cortex.

    Science.gov (United States)

    Storchi, Riccardo; Zippo, Antonio G; Caramenti, Gian Carlo; Valente, Maurizio; Biella, Gabriele E M

    2012-01-01

    Local Field Potentials (LFPs) integrate multiple neuronal events like synaptic inputs and intracellular potentials. LFP spatiotemporal features are particularly relevant in view of their applications both in research (e.g. for understanding brain rhythms, inter-areal neural communication and neuronal coding) and in the clinics (e.g. for improving invasive Brain-Machine Interface devices). However the relation between LFPs and spikes is complex and not fully understood. As spikes represent the fundamental currency of neuronal communication this gap in knowledge strongly limits our comprehension of neuronal phenomena underlying LFPs. We investigated the LFP-spike relation during tactile stimulation in primary somatosensory (S-I) cortex in the rat. First we quantified how reliably LFPs and spikes code for a stimulus occurrence. Then we used the information obtained from our analyses to design a predictive model for spike occurrence based on LFP inputs. The model was endowed with a flexible meta-structure whose exact form, both in parameters and structure, was estimated by using a multi-objective optimization strategy. Our method provided a set of nonlinear simple equations that maximized the match between models and true neurons in terms of spike timings and Peri Stimulus Time Histograms. We found that both LFPs and spikes can code for stimulus occurrence with millisecond precision, showing, however, high variability. Spike patterns were predicted significantly above chance for 75% of the neurons analysed. Crucially, the level of prediction accuracy depended on the reliability in coding for the stimulus occurrence. The best predictions were obtained when both spikes and LFPs were highly responsive to the stimuli. Spike reliability is known to depend on neuron intrinsic properties (i.e. on channel noise) and on spontaneous local network fluctuations. Our results suggest that the latter, measured through the LFP response variability, play a dominant role. PMID:22586452

  10. Predicting spike occurrence and neuronal responsiveness from LFPs in primary somatosensory cortex.

    Directory of Open Access Journals (Sweden)

    Riccardo Storchi

    Full Text Available Local Field Potentials (LFPs integrate multiple neuronal events like synaptic inputs and intracellular potentials. LFP spatiotemporal features are particularly relevant in view of their applications both in research (e.g. for understanding brain rhythms, inter-areal neural communication and neuronal coding and in the clinics (e.g. for improving invasive Brain-Machine Interface devices. However the relation between LFPs and spikes is complex and not fully understood. As spikes represent the fundamental currency of neuronal communication this gap in knowledge strongly limits our comprehension of neuronal phenomena underlying LFPs. We investigated the LFP-spike relation during tactile stimulation in primary somatosensory (S-I cortex in the rat. First we quantified how reliably LFPs and spikes code for a stimulus occurrence. Then we used the information obtained from our analyses to design a predictive model for spike occurrence based on LFP inputs. The model was endowed with a flexible meta-structure whose exact form, both in parameters and structure, was estimated by using a multi-objective optimization strategy. Our method provided a set of nonlinear simple equations that maximized the match between models and true neurons in terms of spike timings and Peri Stimulus Time Histograms. We found that both LFPs and spikes can code for stimulus occurrence with millisecond precision, showing, however, high variability. Spike patterns were predicted significantly above chance for 75% of the neurons analysed. Crucially, the level of prediction accuracy depended on the reliability in coding for the stimulus occurrence. The best predictions were obtained when both spikes and LFPs were highly responsive to the stimuli. Spike reliability is known to depend on neuron intrinsic properties (i.e. on channel noise and on spontaneous local network fluctuations. Our results suggest that the latter, measured through the LFP response variability, play a dominant role.

  11. Estrogen intervention in microvascular morphology and choline acetyltransferase expression in rat hippocampal neurons in chronic cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Zhenjun Yang; Hongwei Yan; Guomin Zhang; Zhihong Chen; Jingfeng Xue

    2011-01-01

    We observed dynamic changes in microvessels and a protective effect of estrogen on chronic cerebral ischemia ovariectomized rat models established through permanent occlusion of bilateral carotid arteries at 7, 14 and 21 days. The results revealed that estrogen improved microvasculature in the hippocampus of chronic cerebral ischemic rats, upregulated Bcl-2 protein expression, downregulated Bax protein expression, increased choline acetyltransferase expression in hippocampal cholinergic neurons, and suppressed hippocampal neuronal apoptosis. These findings indicate that estrogen can protect hippocampal neurons in rats with chronic cerebral ischemia.

  12. The cerebral cortex of Albert Einstein: a description and preliminary analysis of unpublished photographs.

    Science.gov (United States)

    Falk, Dean; Lepore, Frederick E; Noe, Adrianne

    2013-04-01

    Upon his death in 1955, Albert Einstein's brain was removed, fixed and photographed from multiple angles. It was then sectioned into 240 blocks, and histological slides were prepared. At the time, a roadmap was drawn that illustrates the location within the brain of each block and its associated slides. Here we describe the external gross neuroanatomy of Einstein's entire cerebral cortex from 14 recently discovered photographs, most of which were taken from unconventional angles. Two of the photographs reveal sulcal patterns of the medial surfaces of the hemispheres, and another shows the neuroanatomy of the right (exposed) insula. Most of Einstein's sulci are identified, and sulcal patterns in various parts of the brain are compared with those of 85 human brains that have been described in the literature. To the extent currently possible, unusual features of Einstein's brain are tentatively interpreted in light of what is known about the evolution of higher cognitive processes in humans. As an aid to future investigators, these (and other) features are correlated with blocks on the roadmap (and therefore histological slides). Einstein's brain has an extraordinary prefrontal cortex, which may have contributed to the neurological substrates for some of his remarkable cognitive abilities. The primary somatosensory and motor cortices near the regions that typically represent face and tongue are greatly expanded in the left hemisphere. Einstein's parietal lobes are also unusual and may have provided some of the neurological underpinnings for his visuospatial and mathematical skills, as others have hypothesized. Einstein's brain has typical frontal and occipital shape asymmetries (petalias) and grossly asymmetrical inferior and superior parietal lobules. Contrary to the literature, Einstein's brain is not spherical, does not lack parietal opercula and has non-confluent Sylvian and inferior postcentral sulci.

  13. Tyrosine inhibits creatine kinase activity in cerebral cortex of young rats.

    Science.gov (United States)

    de Andrade, Rodrigo Binkowski; Gemelli, Tanise; Rojas, Denise Bertin; Funchal, Cláudia; Dutra-Filho, Carlos Severo; Wannmacher, Clovis Milton Duval

    2011-09-01

    Tyrosine accumulates in inborn errors of tyrosine catabolism, especially in tyrosinemia type II, where tyrosine levels are highly elevated in tissues and physiological fluids of affected patients. Tyrosinemia type II is a disorder of autosomal recessive inheritance characterized by neurological symptoms similar to those observed in patients with creatine deficiency syndromes. Considering that the mechanisms of brain damage in these disorders are poorly known, in the present study our main objective was to investigate the in vivo and in vitro effects of different concentrations and preincubation times of tyrosine on cytosolic and mitochondrial creatine kinase activities of the cerebral cortex from 14-day-old Wistar rats. The cytosolic CK was reduced by 15% at 1 mM and 32% at 2 mM tyrosine. Similarly, the mitochondrial CK was inhibited by 15% at 1 mM and 22% at 2 mM tyrosine. We observed that the inhibition caused by tyrosine was concentration-dependent and was prevented by reduced glutathione. Results also indicated that mitochondrial, but not cytosolic creatine kinase activity was inhibited by tyrosine in a time-dependent way. Finally, a single injection of L-Tyrosine methyl ester administered i.p. decreased cytosolic (31%) and mitochondrial (18%) creatine kinase activities of brain cortex from rats. Considering that creatine kinase is an enzyme dependent of thiol residues for its function and tyrosine induces oxidative stress, the results suggest that the inhibition caused by tyrosine might occur by oxidation of essential sulfhydryl groups of the enzyme. In case this also occurs in patients with tyrosinemia, it is possible that creatine kinase inhibition may contribute to the neurological dysfunction characteristic of tyrosinemia.

  14. Effects of microgravity on muscle and cerebral cortex: a suggested interaction

    Science.gov (United States)

    D'Amelio, F.; Fox, R. A.; Wu, L. C.; Daunton, N. G.; Corcoran, M. L.

    The ``slow'' antigravity muscle adductor longus was studied in rats after 14 days of spaceflight (SF). The techniques employed included standard methods for light microscopy, neural cell adhesion molecule (N-CAM) immunocytochemistry and electron microscopy. Light and electron microscopy revealed myofiber atrophy, segmental necrosis and regenerative myofibers. Regenerative myofibers were N-CAM immunoreactive (N-CAM-IR). The neuromuscular junctions showed axon terminals with a decrease or absence of synaptic vesicles, degenerative changes, vacant axonal spaces and changes suggestive of axonal sprouting. No alterations of muscle spindles was seen either by light or electron microscopy. These observations suggest that muscle regeneration and denervation and synaptic remodeling at the level of the neuromuscular junction may take place during spaceflight. In a separate study, GABA immunoreactivity (GABA-IR) was evaluated at the level of the hindlimb representation of the rat somatosensory cortex after 14 days of hindlimb unloading by tail suspension (``simulated'' microgravity). A reduction in number of GABA-immunoreactive cells with respect to the control animals was observed in layer Va and Vb. GABA-IR terminals were also reduced in the same layers, particularly those terminals surrounding the soma and apical dendrites of pyramidal cells in layer Vb. On the basis of previous morphological and behavioral studies of the neuromuscular system after spaceflight and hindlimb suspension it is suggested that after limb unloading there are alterations of afferent signaling and feedback information from intramuscular receptors to the cerebral cortex due to modifications in the reflex organization of hindlimb muscle groups. We propose that the changes observed in GABA immunoreactivity of cells and terminals is an expression of changes in their modulatory activity to compensate for the alterations in the afferent information.

  15. Rich club organization of macaque cerebral cortex and its role in network communication.

    Directory of Open Access Journals (Sweden)

    Logan Harriger

    Full Text Available Graph-theoretical analysis of brain connectivity data has revealed significant features of brain network organization across a range of species. Consistently, large-scale anatomical networks exhibit highly nonrandom attributes including an efficient small world modular architecture, with distinct network communities that are interlinked by hub regions. The functional importance of hubs motivates a closer examination of their mutual interconnections, specifically to examine the hypothesis that hub regions are more densely linked than expected based on their degree alone, i.e. forming a central rich club. Extending recent findings of rich club topology in the cat and human brain, this report presents evidence for the existence of rich club organization in the cerebral cortex of a non-human primate, the macaque monkey, based on a connectivity data set representing a collation of numerous tract tracing studies. Rich club regions comprise portions of prefrontal, parietal, temporal and insular cortex and are widely distributed across network communities. An analysis of network motifs reveals that rich club regions tend to form star-like configurations, indicative of their central embedding within sets of nodes. In addition, rich club nodes and edges participate in a large number of short paths across the network, and thus contribute disproportionately to global communication. As rich club regions tend to attract and disperse communication paths, many of the paths follow a characteristic pattern of first increasing and then decreasing node degree. Finally, the existence of non-reciprocal projections imposes a net directional flow of paths into and out of the rich club, with some regions preferentially attracting and others dispersing signals. Overall, the demonstration of rich club organization in a non-human primate contributes to our understanding of the network principles underlying neural connectivity in the mammalian brain, and further supports

  16. Objective classification of motion- and direction-sensitive neurons in primary somatosensory cortex of awake monkeys.

    Science.gov (United States)

    Warren, S; Hamalainen, H A; Gardner, E P

    1986-09-01

    In order to classify movement-sensitive neurons in SI cortex, and to estimate their relative distribution, we have developed a new simple method for controlled motion of textured surfaces across the skin, as well as a set of objective criteria for determining direction selectivity. Moving stimuli were generated using 5 mm thick precision gear wheels, whose teeth formed a grafting. They were mounted on the shafts of low-torque potentiometers (to measure the speed and direction of movement) and rolled manually across the skin using the potentiometer shaft as an axle. As the grafting wheel was advanced, its ridges sequentially contacted a specific set of points on the skin, leaving gaps of defined spacing that were unstimulated. This stimulus was reproducible from trial to trial and produced little distention of the skin. Three objective criteria were used to categorize responses: the ratio of responses to motion in the most and least preferred directions [direction index (DI)], the difference between mean firing rates in the two directions divided by the average standard deviation [index of discriminability (delta'e)], and statistical tests. Neurons were classified as direction sensitive if DI greater than 35, delta's greater than or equal to 1.35 (equivalent to 75% correct discrimination by an unbiased observer), and firing rates in most- and least-preferred directions were significantly different (P less than 0.05). Good agreement was found between the three classification schemes. Recordings were made from 1,020 cortical neurons in the hand and forearm regions of primary somatosensory cortex (areas 3b, 1 and 2) of five macaque monkeys. Tangential motion across the skin was found to be an extremely effective stimulus for SI cortical neurons. Two hundred eighty six of 757 tactile neurons (38%) responded more vigorously to moving stimuli than to pressure or tapping the skin. One hundred twenty-one cells were tested with moving gratings and were classified according

  17. Nonlinear properties of medial entorhinal cortex neurons reveal frequency selectivity during multi-sinusoidal stimulation.

    Directory of Open Access Journals (Sweden)

    Christophe eMagnani

    2014-08-01

    Full Text Available The neurons in layer II of the medial entorhinal cortex are part of the grid cell network involved in the representation of space. Many of these neurons are likely to be stellate cells with specific oscillatory and firing properties important for their function. A fundamental understanding of the nonlinear basis of these oscillatory properties is critical for the development of theories of grid cell firing. In order to evaluate the behavior of stellate neurons, measurements of their quadratic responses were used to estimate a second order Volterra kernel. This paper uses an operator theory, termed quadratic sinusoidal analysis (QSA, which quantitatively determines that the quadratic response accounts for a major part of the nonlinearity observed at membrane potential levels characteristic of normal synaptic events. Practically, neurons were probed with multi-sinusoidal stimulations to determine a Hermitian operator that captures the quadratic function in the frequency domain. We have shown that the frequency content of the stimulation plays an important role in the characteristics of the nonlinear response, which can distort the linear response as well. Stimulations with enhanced low frequency amplitudes evoked a different nonlinear response than broadband profiles. The nonlinear analysis was also applied to spike frequencies and it was shown that the nonlinear response of subthreshold membrane potential at resonance frequencies near the threshold is similar to the nonlinear response of spike trains.

  18. Effects of sericin on heme oxygenase-1 expression in the hippocampus and cerebral cortex of type 2 diabetes mellitus rats

    Institute of Scientific and Technical Information of China (English)

    Zhihona Chen; Yaqiang He; Wenliang Fu; Jingfeng Xue

    2011-01-01

    Previous studies have demonstrated that sericin effectively reduces blood glucose, and protects islet cells, as well as the gonads and kidneys. However, whether sericin improves diabetes mellitus-induced structural and functional problems in the central nervous system remains poorly understood. Rat models of type 2 diabetes mellitus were established by intraperitoneal injection of streptozotocin. The present study observed histological changes in the hippocampus and cerebral cortex, as well as heme oxygenase-1 expression, and explored sericin effects on the central nervous system in diabetic rats. Pathological damage to neural cells in the rat hippocampus and cerebral cortex was relieved following intragastric administration of sericin at a dose of 2.4 g/kg for 35 consecutive days. Heme oxygenase-1 protein and mRNA expressions were decreased in the hippocampus and cerebral cortex of diabetes mellitus rats after sericin treatment. The results suggest that sericin plays a protective effect on the nervous system by decreasing the high expression of heme oxygenase-1 following diabetes mellitus.

  19. Activity-dependent structural plasticity after aversive experiences in amygdala and auditory cortex pyramidal neurons.

    Science.gov (United States)

    Gruene, Tina; Flick, Katelyn; Rendall, Sam; Cho, Jin Hyung; Gray, Jesse; Shansky, Rebecca

    2016-07-22

    The brain is highly plastic and undergoes changes in response to many experiences. Learning especially can induce structural remodeling of dendritic spines, which is thought to relate to memory formation. Classical Pavlovian fear conditioning (FC) traditionally pairs an auditory cue with an aversive footshock, and has been widely used to study neural processes underlying associative learning and memory. Past research has found dendritic spine changes after FC in several structures. But, due to heterogeneity of cells within brain structures and limitations of traditional neuroanatomical techniques, it is unclear if all cells included in analyses were actually active during learning processes, even if known circuits are isolated. In this study, we employed a novel approach to analyze structural plasticity explicitly in neurons activated by exposure to either cued or uncued footshocks. We used male and female Arc-dVenus transgenic mice, which express the Venus fluorophore driven by the activity-related Arc promoter, to identify neurons that were active during either scenario. We then targeted fluorescent microinjections to Arc+ and neighboring Arc- neurons in the basolateral area of the amygdala (BLA) and auditory association cortex (TeA). In both BLA and TeA, Arc+ neurons had reduced thin and mushroom spine densities compared to Arc- neurons. This effect was present in males and females alike and also in both cued and uncued shock groups. Overall, this study adds to our understanding of how neuronal activity affects structural plasticity, and represents a methodological advance in the ways we can directly relate structural changes to experience-related neural activity.

  20. Activity-dependent structural plasticity after aversive experiences in amygdala and auditory cortex pyramidal neurons.

    Science.gov (United States)

    Gruene, Tina; Flick, Katelyn; Rendall, Sam; Cho, Jin Hyung; Gray, Jesse; Shansky, Rebecca

    2016-07-22

    The brain is highly plastic and undergoes changes in response to many experiences. Learning especially can induce structural remodeling of dendritic spines, which is thought to relate to memory formation. Classical Pavlovian fear conditioning (FC) traditionally pairs an auditory cue with an aversive footshock, and has been widely used to study neural processes underlying associative learning and memory. Past research has found dendritic spine changes after FC in several structures. But, due to heterogeneity of cells within brain structures and limitations of traditional neuroanatomical techniques, it is unclear if all cells included in analyses were actually active during learning processes, even if known circuits are isolated. In this study, we employed a novel approach to analyze structural plasticity explicitly in neurons activated by exposure to either cued or uncued footshocks. We used male and female Arc-dVenus transgenic mice, which express the Venus fluorophore driven by the activity-related Arc promoter, to identify neurons that were active during either scenario. We then targeted fluorescent microinjections to Arc+ and neighboring Arc- neurons in the basolateral area of the amygdala (BLA) and auditory association cortex (TeA). In both BLA and TeA, Arc+ neurons had reduced thin and mushroom spine densities compared to Arc- neurons. This effect was present in males and females alike and also in both cued and uncued shock groups. Overall, this study adds to our understanding of how neuronal activity affects structural plasticity, and represents a methodological advance in the ways we can directly relate structural changes to experience-related neural activity. PMID:27155146

  1. Cellular and synaptic localization of EAAT2a in human cerebral cortex

    Directory of Open Access Journals (Sweden)

    Marcello eMelone

    2011-01-01

    Full Text Available We used light and electron microscopic immunocytochemical techniques to analyze the distribution, cellular and synaptic localization of EAAT2, the main glutamate transporter, in normal human neocortex. EAAT2a immunoreactivity was in all layers and consisted of small neuropilar puncta and rare cells. In white matter EAAT2a+ cells were numerous. Electron microscopic studies showed that in gray matter ∼77% of immunoreactive elements were astrocytic processes, ∼14% axon terminals, ∼2.8% dendrites, whereas ∼5% were unidentifiable. In white matter, ∼81% were astrocytic processes, ∼17% were myelinated axons and ∼2.0% were unidentified. EAAT2a immunoreactivity was never in microglial cells and oligodendrocytes. Pre-embedding electron microscopy showed that ∼67% of EAAT2a expressed at (or in the vicinity of asymmetric synapses was in astrocytes, ∼17% in axon terminals, while ∼13% was both in astrocytes and in axons. Post-embeddeding electron microscopy studies showed that in astrocytic processes contacting asymmetric synapses and in axon terminals, gold particle density was ∼25.1 and ∼2.8 particles/µm2, respectively, and was concentrated in a membrane region extending for ∼300 nm from the active zone edge. Besides representing the first detailed description of EAAT2a in human cerebral cortex, these findings may contribute to understanding its role in the pathophysiology of neuropsychiatric diseases.

  2. Using Individualized Brain Network for Analyzing Structural Covariance of the Cerebral Cortex in Alzheimer's Patients

    Science.gov (United States)

    Kim, Hee-Jong; Shin, Jeong-Hyeon; Han, Cheol E.; Kim, Hee Jin; Na, Duk L.; Seo, Sang Won; Seong, Joon-Kyung

    2016-01-01

    Cortical thinning patterns in Alzheimer's disease (AD) have been widely reported through conventional regional analysis. In addition, the coordinated variance of cortical thickness in different brain regions has been investigated both at the individual and group network levels. In this study, we aim to investigate network architectural characteristics of a structural covariance network (SCN) in AD, and further to show that the structural covariance connectivity becomes disorganized across the brain regions in AD, while the normal control (NC) subjects maintain more clustered and consistent coordination in cortical atrophy variations. We generated SCNs directly from T1-weighted MR images of individual patients using surface-based cortical thickness data, with structural connectivity defined as similarity in cortical thickness within different brain regions. Individual SCNs were constructed using morphometric data from the Samsung Medical Center (SMC) dataset. The structural covariance connectivity showed higher clustering than randomly generated networks, as well as similar minimum path lengths, indicating that the SCNs are “small world.” There were significant difference between NC and AD group in characteristic path lengths (z = −2.97, p brain regions with co-atrophy of the cerebral cortex due to normal aging or AD. We applied our method to the AD Neuroimaging Initiative (ADNI) data to show consistency in results with the SMC dataset. PMID:27635121

  3. Tyrosine impairs enzymes of energy metabolism in cerebral cortex of rats.

    Science.gov (United States)

    de Andrade, Rodrigo Binkowski; Gemelli, Tanise; Rojas, Denise Bertin; Funchal, Cláudia; Dutra-Filho, Carlos Severo; Wannmacher, Clovis Milton Duval

    2012-05-01

    Tyrosine levels are abnormally elevated in tissues and physiological fluids of patients with inborn errors of tyrosine catabolism, especially in tyrosinemia type II, which is caused by deficiency of tyrosine aminotransferase and provokes eyes, skin, and central nervous system disturbances. Considering that the mechanisms of brain damage in these disorders are poorly known, in this study, we investigated the in vivo and in vitro effects of tyrosine on some parameters of energy metabolism in cerebral cortex of 14-day-old Wistar rats. We observed that 2 mM tyrosine inhibited in vitro the pyruvate kinase (PK) activity and that this inhibition was prevented by 1 mM reduced glutathione with 30, 60, and 90 min of preincubation. Moreover, administration of tyrosine methyl ester (TME) (0.5 mg/g of body weight) decreased the activity of PK and this reduction was prevented by pre-treatment with creatine (Cr). On the other hand, tyrosine did not alter adenylate kinase (AK) activity in vitro, but administration of TME enhanced AK activity not prevented by Cr pre-treatment. Finally, TME administration decreased the activity of CK from cytosolic and mitochondrial fractions and this diminution was prevented by Cr pre-treatment. The results suggest that tyrosine alters essential sulfhydryl groups necessary for CK and PK functions, possibly through oxidative stress. In case this also occurs in the patients, it is possible that energy metabolism alterations may contribute, along with other mechanisms, to the neurological dysfunction of hypertyrosinemias.

  4. Effects of weak amplitude-modulated microwave fields on calcium efflux from awake cat cerebral cortex

    International Nuclear Information System (INIS)

    Calcium (45Ca2+) efflux was studied from preloaded cortex in cats immobilized under local anesthesia, and exposed to a 3.0-mW/cm2 450-MHz field, sinusoidally amplitude modulated at 16 Hz modulation depth 85%). Tissue dosimetry showed a field of 33 V/m in the interhemispheric fissure (rate of energy deposition 0.29 W/kg). Field exposure lasted 60 min. By comparison with controls, efflux curves from field exposed brains were disrupted by waves of increased 45Ca2+ efflux. These waves were irregular in amplitude and duration, but many exhibited periods of 20-30 min. They continued into the postexposure period. Binomial probability analysis indicates that the field-exposed efflux curves constitute a different population from controls at a confidence level of 0.96. In about 70% of cases, initiation of field exposure was followed by increased end-tidal CO2 excretion for about 5 min. However, hypercapnea induced by hypoventilation did not elicit increased 45Ca2+ efflux. Thus this increase with exposure does not appear to arise as a secondary effect of raised cerebral CO2 levels. Radioactivity measurements in cortical samples after superfusion showed 45Ca2+ penetration at about 1.7 mm/hr, consistent with diffusion of the ion in free solution

  5. The effect of intervention according to muscle contraction type on the cerebral cortex of the elderly

    Science.gov (United States)

    Kang, Jeong-il; Jeong, Dae-Keun; Choi, Hyun

    2016-01-01

    [Purpose] Here we investigated the activity of the cerebral cortex after resistance training in the elderly. We evaluated the clinical neuropsychological basis of 2 contractile types, and determined the usefulness of a movement-related cortical potential (MRCP) from an electroencephalography (EEG). [Subjects and Methods] The subjects were 11 females and 11 males aged between 65 and 70 years. The subjects were randomly assigned into a group that performed an eccentric contraction exercise (experimental group I, n=11) and a group that performed a concentric contraction exercise (experimental group II, n=11). We measured activities of the rectus femoris, vastus medialis, and vastus lateralis in the non-dominant lower extremity by using surface electromyography (EMG), and measured brain activity using EEG before conducting an intervention. An intervention was conducted 40 minutes per session, once a day, 3 times a week for 4 weeks. [Results] After the intervention, activity in C4, the Cz area and rectus femoris were significantly different. [Conclusion] Our results demonstrate that MRCP from an EEG has the advantage of being non-invasive and cost-effective. Nonetheless, prospective studies are needed to reveal the specific mechanism underlying eccentric contraction exercise, which can provide baseline data for research related to aging and neural plasticity. PMID:27799694

  6. Progesterone and nestorone promote myelin regeneration in chronic demyelinating lesions of corpus callosum and cerebral cortex.

    Science.gov (United States)

    El-Etr, Martine; Rame, Marion; Boucher, Celine; Ghoumari, Abdel M; Kumar, Narender; Liere, Philippe; Pianos, Antoine; Schumacher, Michael; Sitruk-Ware, Regine

    2015-01-01

    Multiple Sclerosis affects mainly women and consists in intermittent or chronic damages to the myelin sheaths, focal inflammation, and axonal degeneration. Current therapies are limited to immunomodulators and antiinflammatory drugs, but there is no efficient treatment for stimulating the endogenous capacity of myelin repair. Progesterone and synthetic progestins have been shown in animal models of demyelination to attenuate myelin loss, reduce clinical symptoms severity, modulate inflammatory responses and partially reverse the age-dependent decline in remyelination. Moreover, progesterone has been demonstrated to promote myelin formation in organotypic cultures of cerebellar slices. In the present study, we show that progesterone and the synthetic 19-nor-progesterone derivative Nestorone® promote the repair of severe chronic demyelinating lesions induced by feeding cuprizone to female mice for up to 12 weeks. Progesterone and Nestorone increase the density of NG2(+) oligodendrocyte progenitor cells and CA II(+) mature oligodendrocytes and enhance the formation of myelin basic protein (MBP)- and proteolipid protein (PLP)-immunoreactive myelin. However, while demyelination in response to cuprizone was less marked in corpus callosum than in cerebral cortex, remyelination appeared earlier in the former. The remyelinating effect of progesterone was progesterone receptor (PR)-dependent, as it was absent in PR-knockout mice. Progesterone and Nestorone also decreased (but did not suppress) neuroinflammatory responses, specifically astrocyte and microglial cell activation. Therefore, some progestogens are promising therapeutic candidates for promoting the regeneration of myelin.

  7. Manatee cerebral cortex: cytoarchitecture of the frontal region in Trichechus manatus latirostris.

    Science.gov (United States)

    Reep, R L; Johnson, J I; Switzer, R C; Welker, W I

    1989-01-01

    Members of the order Sirenia are unique among mammals in being the only totally aquatic herbivores. They display correspondingly specialized physiological, behavioral and anatomical features. There have been few reports concerning sirenian neuroanatomy, and most of these have consisted of gross anatomical observations. Our interest in Sirenia stems from the desire to understand neuroanatomical specializations in the context of behavior and the effort to elucidate trends in mammalian brain evolution. The architecture of frontal regions of cerebral cortex was investigated in several brains of the Florida manatee, Trichechus manatus latirostris. Through observation of sections stained for Nissl substance or myelinated fibers, several distinct cortical areas were identified on the basis of laminar organization. These range from areas with poorly defined laminae to those having 6 well-defined layers, some of which exhibit sublayers. Two cortical areas exhibit pronounced cell clusters in layer VI, and these stain positively for acetylcholinesterase and cytochrome oxidase. We hypothesize that these clusters may be involved in perioral tactile bristle function. Certain of our findings are consistent with previous observations in the literature on the brains of dugongs. On the basis of their lamination patterns, these frontal cortical areas appear to be organized into concentric zones of allocortex, mesocortex and isocortex. PMID:2611642

  8. Neuroprotective effects of tadalafil on gerbil dopaminergic neurons following cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Kwang Taek Kim; Kyung Jin Chung; Han Sae Lee; Il Gyu Ko; Chang Ju Kim; Yong Gil Na; Khae Hawn Kim

    2013-01-01

    Impairment of dopamine function, which is known to have major effects on behaviors and cognition, is one of the main problems associated with cerebral ischemia. Tadalafil, a long-acting phosphodiesterase type-5 inhibitor, is known to ameliorate neurologic impairment induced by brain injury, but not in dopaminergic regions. We investigated the neuroprotective effects of treatment with tadalafil on cyclic guanosine monophosphate level and dopamine function following cerebral ischemia. Forty adult Mongolian gerbils were randomly and evenly divided into five groups (n = 8 in each group): Sham-operation group, cerebral ischemia-induced and 0, 0.1, 1, and 10 mg/kg tadalafil-treated groups, respectively. Tadalafil dissolved in distilled water was administered orally for 7 consecutive days, starting 1 day after surgery. Cyclic guanosine monophosphate assay and immunohistochemistry were performed for thyrosine hydroxylase expression and western blot analysis for dopamine D2 receptor expression. A decrease in cyclic guanosine monophosphate level following cerebral ischemia was found with an increase in thyrosine hydroxylase activity and a decrease in dopamine D2 receptor expression in the striatum and substantia nigra region. However, treatment with tadalafil increased cyclic guanosine monophosphate expression, suppressed thyrosine hydroxylase expression and increased dopamine D2 receptor expression in the striatum and substantia nigra region in a dose-dependent manner. Tadalafil might ameliorate cerebral ischemia-induced dopaminergic neuron injury. Therefore, tadalafil has the potential as a new neuroprotective treatment strategy for cerebral ischemic injury.

  9. Neuroprotective effects of tadalafil on gerbil dopaminergic neurons following cerebral ischemia.

    Science.gov (United States)

    Kim, Kwang Taek; Chung, Kyung Jin; Lee, Han Sae; Ko, Il Gyu; Kim, Chang Ju; Na, Yong Gil; Kim, Khae Hawn

    2013-03-15

    Impairment of dopamine function, which is known to have major effects on behaviors and cognition, is one of the main problems associated with cerebral ischemia. Tadalafil, a long-acting phosphodiesterase type-5 inhibitor, is known to ameliorate neurologic impairment induced by brain injury, but not in dopaminergic regions. We investigated the neuroprotective effects of treatment with tadalafil on cyclic guanosine monophosphate level and dopamine function following cerebral ischemia. Forty adult Mongolian gerbils were randomly and evenly divided into five groups (n = 8 in each group): Sham-operation group, cerebral ischemia-induced and 0, 0.1, 1, and 10 mg/kg tadalafil-treated groups, respectively. Tadalafil dissolved in distilled water was administered orally for 7 consecutive days, starting 1 day after surgery. Cyclic guanosine monophosphate assay and immunohistochemistry were performed for thyrosine hydroxylase expression and western blot analysis for dopamine D2 receptor expression. A decrease in cyclic guanosine monophosphate level following cerebral ischemia was found with an increase in thyrosine hydroxylase activity and a decrease in dopamine D2 receptor expression in the striatum and substantia nigra region. However, treatment with tadalafil increased cyclic guanosine monophosphate expression, suppressed thyrosine hydroxylase expression and increased dopamine D2 receptor expression in the striatum and substantia nigra region in a dose-dependent manner. Tadalafil might ameliorate cerebral ischemia-induced dopaminergic neuron injury. Therefore, tadalafil has the potential as a new neuroprotective treatment strategy for cerebral ischemic injury. PMID:25206715

  10. Effect of a low-dose x-ray irradiation on the development and differentiation of the cerebral cortex, (15)

    International Nuclear Information System (INIS)

    Mice of 17 day's gestation received x-rays of 10 R, 25 R, or 100 R, and those of 13 or 15 day's gestation received 10 R in a single exposure. These irradiated fetuses were examined for the weight of the brain, thickness of the cerebral cortex, density of the cortical cells and branching of the pyramidal cells in the fifth layer of the cortex 12 weeks after birth. Decrease in the thickness of the cortex was observed in the mice which received 100 R at 17 day's gestation. A decrease in the branching index of the pyramidal cells was found in the mice which received 100 R. Although a decreasing tendency of the branching index was also recognized in those which received 10 R at 13 days of gestation, showing no statistically significant difference. (Ueda, J.)

  11. Electroacupuncture stimulation of the brachial plexus trunk on the healthy side promotes brain-derived neurotrophic factor mRNA expression in the ischemic cerebral cortex of a rat model of cerebral ischemia/reperfusion injury

    Institute of Scientific and Technical Information of China (English)

    Zongjun Guo; Lumin Wang

    2012-01-01

    A rat model of cerebral ischemia/reperfusion was established by suture occlusion of the left middle cerebral artery. In situ hybridization results showed that the number of brain-derived neurotrophic factor mRNA-positive cells in the ischemic rat cerebral cortex increased after cerebral ischemia/ reperfusion injury. Low frequency continuous wave electroacupuncture (frequency 2-6 Hz, current intensity 2 mA) stimulation of the brachial plexus trunk on the healthy (right) side increased the number of brain-derived neurotrophic factor mRNA-positive cells in the ischemic cerebral cortex 14 days after cerebral ischemia/reperfusion injury. At the same time, electroacupuncture stimulation of the healthy brachial plexus truck significantly decreased neurological function scores and alleviated neurological function deficits. These findings suggest that electroacupuncture stimulation of the brachial plexus trunk on the healthy (right) side can greatly increase brain-derived neurotrophic factor mRNA expression and improve neurological function.

  12. Color-tuned neurons are spatially clustered according to color preference within alert macaque posterior inferior temporal cortex

    OpenAIRE

    Conway, Bevil R.; Tsao, Doris Y

    2009-01-01

    Large islands of extrastriate cortex that are enriched for color-tuned neurons have recently been described in alert macaque using a combination of functional magnetic resonance imaging (fMRI) and single-unit recording. These millimeter-sized islands, dubbed “globs,” are scattered throughout the posterior inferior temporal cortex (PIT), a swath of brain anterior to area V3, including areas V4, PITd, and posterior TEO. We investigated the micro-organization of neurons within the globs. We used...

  13. Hemodynamic changes in a rat parietal cortex after endothelin-1-induced middle cerebral artery occlusion monitored by optical coherence tomography

    Science.gov (United States)

    Liu, Jian; Ma, Yushu; Dou, Shidan; Wang, Yi; La, Dongsheng; Liu, Jianghong; Ma, Zhenhe

    2016-07-01

    A blockage of the middle cerebral artery (MCA) on the cortical branch will seriously affect the blood supply of the cerebral cortex. Real-time monitoring of MCA hemodynamic parameters is critical for therapy and rehabilitation. Optical coherence tomography (OCT) is a powerful imaging modality that can produce not only structural images but also functional information on the tissue. We use OCT to detect hemodynamic changes after MCA branch occlusion. We injected a selected dose of endothelin-1 (ET-1) at a depth of 1 mm near the MCA and let the blood vessels follow a process first of occlusion and then of slow reperfusion as realistically as possible to simulate local cerebral ischemia. During this period, we used optical microangiography and Doppler OCT to obtain multiple hemodynamic MCA parameters. The change trend of these parameters from before to after ET-1 injection clearly reflects the dynamic regularity of the MCA. These results show the mechanism of the cerebral ischemia-reperfusion process after a transient middle cerebral artery occlusion and confirm that OCT can be used to monitor hemodynamic parameters.

  14. Preserved number of entorhinal cortex layer II neurons in aged macaque monkeys

    Science.gov (United States)

    Gazzaley, A. H.; Thakker, M. M.; Hof, P. R.; Morrison, J. H.; Bloom, F. E. (Principal Investigator)

    1997-01-01

    The perforant path, which consists of the projection from the layer II neurons of the entorhinal cortex to the outer molecular layer of the dentate gyrus, is a critical circuit involved in learning and memory formation. Accordingly, disturbances in this circuit may contribute to age-related cognitive deficits. In a previous study, we demonstrated a decrease in N-methyl-D-aspartate receptor subunit 1 immunofluorescence intensity in the outer molecular layer of aged macaque monkeys. In this study, we used the optical fractionator, a stereological method, to determine if a loss of layer II neurons occurred in the same animals in which the N-methyl-D-aspartate receptor subunit 1 alteration was observed. Our results revealed no significant differences in the number of layer II neurons between juvenile, young adult, and aged macaque monkeys. These results suggest that the circuit-specific decrease in N-methyl-D-aspartate receptor subunit 1 reported previously occurs in the absence of structural compromise of the perforant path, and thus may be linked to an age-related change in the physiological properties of this circuit.

  15. Representation of others' action by neurons in monkey medial frontal cortex.

    Science.gov (United States)

    Yoshida, Kyoko; Saito, Nobuhito; Iriki, Atsushi; Isoda, Masaki

    2011-02-01

    Successful social interaction depends on not only the ability to identify with others but also the ability to distinguish between aspects of self and others. Although there is considerable knowledge of a shared neural substrate between self-action and others' action, it remains unknown where and how in the brain the action of others is uniquely represented. Exploring such agent-specific neural codes is important because one's action and intention can differ between individuals. Moreover, the assignment of social agency breaks down in a range of mental disorders. Here, using two monkeys monitoring each other's action for adaptive behavioral planning, we show that the medial frontal cortex (MFC) contains a group of neurons that selectively encode others' action. These neurons, observed in both dominant and submissive monkeys, were significantly more prevalent in the dorsomedial convexity region of the MFC including the pre-supplementary motor area than in the cingulate sulcus region of the MFC including the rostral cingulate motor area. Further tests revealed that the difference in neuronal activity was not due to gaze direction or muscular activity. We suggest that the MFC is involved in self-other differentiation in the domain of motor action and provides a fundamental neural signal for social learning. PMID:21256015

  16. The von Economo neurons in the frontoinsular and anterior cingulate cortex.

    Science.gov (United States)

    Allman, John M; Tetreault, Nicole A; Hakeem, Atiya Y; Manaye, Kebreten F; Semendeferi, Katerina; Erwin, Joseph M; Park, Soyoung; Goubert, Virginie; Hof, Patrick R

    2011-04-01

    The von Economo neurons (VENs) are large bipolar neurons located in the frontoinsular cortex (FI) and limbic anterior (LA) area in great apes and humans but not in other primates. Our stereological counts of VENs in FI and LA show them to be more numerous in humans than in apes. In humans, small numbers of VENs appear the 36th week postconception, with numbers increasing during the first 8 months after birth. There are significantly more VENs in the right hemisphere in postnatal brains; this may be related to asymmetries in the autonomic nervous system. VENs are also present in elephants and whales and may be a specialization related to very large brain size. The large size and simple dendritic structure of these projection neurons suggest that they rapidly send basic information from FI and LA to other parts of the brain, while slower neighboring pyramids send more detailed information. Selective destruction of VENs in early stages of frontotemporal dementia (FTD) implies that they are involved in empathy, social awareness, and self-control, consistent with evidence from functional imaging. PMID:21534993

  17. Leucine-rich α2-glycoprotein is a novel biomarker of neurodegenerative disease in human cerebrospinal fluid and causes neurodegeneration in mouse cerebral cortex.

    Directory of Open Access Journals (Sweden)

    Masakazu Miyajima

    Full Text Available Leucine-rich α2-glycoprotein (LRG is a protein induced by inflammation. It contains a leucine-rich repeat (LRR structure and easily binds with other molecules. However, the function of LRG in the brain during aging and neurodegenerative diseases has not been investigated. Here, we measured human LRG (hLRG concentration in the cerebrospinal fluid (CSF and observed hLRG expression in post-mortem human cerebral cortex. We then generated transgenic (Tg mice that over-expressed mouse LRG (mLRG in the brain to examine the effects of mLRG accumulation. Finally, we examined protein-protein interactions using a protein microarray method to screen proteins with a high affinity for hLRG. The CSF concentration of hLRG increases with age and is significantly higher in patients with Parkinson's disease with dementia (PDD and progressive supranuclear palsy (PSP than in healthy elderly people, idiopathic normal pressure hydrocephalus (iNPH patients, and individuals with Alzheimer's disease (AD. Tg mice exhibited neuronal degeneration and neuronal decline. Accumulation of LRG in the brains of PDD and PSP patients is not a primary etiological factor, but it is thought to be one of the causes of neurodegeneration. It is anticipated that hLRG CSF levels will be a useful biomarker for the early diagnosis of PDD and PSP.

  18. Protective effects of icariin on neurons injured by cerebral ischemia/reperfusion

    Institute of Scientific and Technical Information of China (English)

    LI Li; ZHOU Qi-xin; SHI Jing-shan

    2005-01-01

    Background It is very important to search for novel anti-ischemia/reperfusion neuroprotective drugs for prevention or treatment of cerebrovascular diseases. Icariin, the major active component of traditional Chinese herb Yinyanghuo, may have a beneficial role for neurons in cerebral ischemia/reperfusion caused by accident. However, it was not clear yet. In this study, we observed the protective effects of icariin on neurons injured by ischemia/reperfusion in vitro and in vivo and investigated its protective mechanism.Methods Cerebral cortical neurons of Wistar rats in primary culture were studied during the different periods of oxygen-glucose deprivation and reperfusion with oxygen and glucose. Cell viability was determined by methyl thiazoleterazolium (MTT) assay. The activity of lactate dehydrogenase (LDH) leaked from neurons, cell apoptosis and the concentration of intracellular free calcium were measured respectively. On the other hand, the mice model of transient cerebral ischemia/reperfusion was made by bilateral occlusion of common carotid arteries and ischemic hypotension/reperfusion. The mice were divided into several groups at random: sham operated group, model group and icariin preventive treatment group. The changes of mice behavioral, activities of superoxide dismutase (SOD) and the content of malondialdehyde (MDA) were measured, respectively. Results Treatment with icariin (final concentration 0.25, 0.5, and 1 mg/L) during ischemia/reperfusion-mimetic incubation in vitro concentration-dependently attenuated neuronal damage with characteristics of increasing injured neuronal absorbance of MTT, decreasing LDH release, decreasing cell apoptosis, and blunting elevation of intracellular calcium concentration. And in vivo the learning and memory abilities significantly decreased,activities of SOD were diminished and MDA level increased obviously in model group,compared with that in sham operated group. But pre-treatment of model mice with icariin (10, 30

  19. Enhancement of an outwardly rectifying chloride channel in hippocampal pyramidal neurons after cerebral ischemia.

    Science.gov (United States)

    Li, Jianguo; Chang, Quanzhong; Li, Xiaoming; Li, Xiawen; Qiao, Jiantian; Gao, Tianming

    2016-08-01

    Cerebral ischemia induces delayed, selective neuronal death in the CA1 region of the hippocampus. The underlying molecular mechanisms remain unclear, but it is known that apoptosis is involved in this process. Chloride efflux has been implicated in the progression of apoptosis in various cell types. Using both the inside-out and whole-cell configurations of the patch-clamp technique, the present study characterized an outwardly rectifying chloride channel (ORCC) in acutely dissociated pyramid neurons in the hippocampus of adult rats. The channel had a nonlinear current-voltage relationship with a conductance of 42.26±1.2pS in the positive voltage range and 18.23±0.96pS in the negative voltage range, indicating an outward rectification pattern. The channel is Cl(-) selective, and the open probability is voltage-dependent. It can be blocked by the classical Cl(-) channel blockers DIDS, SITS, NPPB and glibenclamide. We examined the different changes in ORCC activity in CA1 and CA3 pyramidal neurons at 6, 24 and 48h after transient forebrain ischemia. In the vulnerable CA1 neurons, ORCC activity was persistently enhanced after ischemic insult, whereas in the invulnerable CA3 neurons, no significant changes occurred. Further analysis of channel kinetics suggested that multiple openings are a major contributor to the increase in channel activity after ischemia. Pharmacological blockade of the ORCC partly attenuated cell death in the hippocampal neurons. We propose that the enhanced activity of ORCC might contribute to selective neuronal damage in the CA1 region after cerebral ischemia, and that ORCC may be a therapeutic target against ischemia-induced cell death. PMID:27181516

  20. Redox homeostasis is compromised in vivo by the metabolites accumulating in 3-hydroxy-3-methylglutaryl-CoA lyase deficiency in rat cerebral cortex and liver.

    Science.gov (United States)

    da Rosa, M S; Seminotti, B; Amaral, A U; Fernandes, C G; Gasparotto, J; Moreira, J C F; Gelain, D P; Wajner, M; Leipnitz, G

    2013-12-01

    3-Hydroxy-3-methylglutaryl-CoA lyase (HL) deficiency is a disorder biochemically characterized by the predominant accumulation of 3-hydroxy-3-methylglutarate (HMG), 3-methylglutarate (MGA), 3-methylglutaconate and 3-hydroxyisovalerate in tissues and biological fluids of the affected patients. Neurological symptoms and hepatopathy are commonly found in HL deficiency, especially during metabolic crises. Since the mechanisms of tissue damage in this disorder are not well understood, in the present study we evaluated the ex vivo effects of acute administration of HMG and MGA on important parameters of oxidative stress in cerebral cortex and liver from young rats. In vivo administration of HMG and MGA provoked an increase of carbonyl and carboxy-methyl-lysine formation in cerebral cortex, but not in liver, indicating that these metabolites induce protein oxidative damage in the brain. We also verified that HMG and MGA significantly decreased glutathione concentrations in both cerebral cortex and liver, implying a reduction of antioxidant defenses. Furthermore, HMG and MGA increased 2',7'-dichlorofluorescin oxidation, but did not alter nitrate and nitrite content in cerebral cortex and liver, indicating that HMG and MGA effects are mainly mediated by reactive oxygen species. HMG and MGA also increased the activities of superoxide dismutase and catalase in cerebral cortex and liver, whereas MGA decreased glutathione peroxidase activity in cerebral cortex. Our present data showing a disruption of redox homeostasis in cerebral cortex and liver caused by in vivo administration of HMG and MGA suggest that this pathomechanism may possibly contribute to the brain and liver abnormalities observed in HL-deficient patients. PMID:24127998

  1. Skilled Bimanual Training Drives Motor Cortex Plasticity in Children With Unilateral Cerebral Palsy.

    Science.gov (United States)

    Friel, Kathleen M; Kuo, Hsing-Ching; Fuller, Jason; Ferre, Claudio L; Brandão, Marina; Carmel, Jason B; Bleyenheuft, Yannick; Gowatsky, Jaimie L; Stanford, Arielle D; Rowny, Stefan B; Luber, Bruce; Bassi, Bruce; Murphy, David L K; Lisanby, Sarah H; Gordon, Andrew M

    2016-10-01

    Background Intensive bimanual therapy can improve hand function in children with unilateral spastic cerebral palsy (USCP). We compared the effects of structured bimanual skill training versus unstructured bimanual practice on motor outcomes and motor map plasticity in children with USCP. Objective We hypothesized that structured skill training would produce greater motor map plasticity than unstructured practice. Methods Twenty children with USCP (average age 9.5; 12 males) received therapy in a day camp setting, 6 h/day, 5 days/week, for 3 weeks. In structured skill training (n = 10), children performed progressively more difficult movements and practiced functional goals. In unstructured practice (n = 10), children engaged in bimanual activities but did not practice skillful movements or functional goals. We used the Assisting Hand Assessment (AHA), Jebsen-Taylor Test of Hand Function (JTTHF), and Canadian Occupational Performance Measure (COPM) to measure hand function. We used single-pulse transcranial magnetic stimulation to map the representation of first dorsal interosseous and flexor carpi radialis muscles bilaterally. Results Both groups showed significant improvements in bimanual hand use (AHA; P < .05) and hand dexterity (JTTHF; P < .001). However, only the structured skill group showed increases in the size of the affected hand motor map and amplitudes of motor evoked potentials (P < .01). Most children who showed the most functional improvements (COPM) had the largest changes in map size. Conclusions These findings uncover a dichotomy of plasticity: the unstructured practice group improved hand function but did not show changes in motor maps. Skill training is important for driving motor cortex plasticity in children with USCP.

  2. Using Individualized Brain Network for Analyzing Structural Covariance of the Cerebral Cortex in Alzheimer's Patients.

    Science.gov (United States)

    Kim, Hee-Jong; Shin, Jeong-Hyeon; Han, Cheol E; Kim, Hee Jin; Na, Duk L; Seo, Sang Won; Seong, Joon-Kyung

    2016-01-01

    Cortical thinning patterns in Alzheimer's disease (AD) have been widely reported through conventional regional analysis. In addition, the coordinated variance of cortical thickness in different brain regions has been investigated both at the individual and group network levels. In this study, we aim to investigate network architectural characteristics of a structural covariance network (SCN) in AD, and further to show that the structural covariance connectivity becomes disorganized across the brain regions in AD, while the normal control (NC) subjects maintain more clustered and consistent coordination in cortical atrophy variations. We generated SCNs directly from T1-weighted MR images of individual patients using surface-based cortical thickness data, with structural connectivity defined as similarity in cortical thickness within different brain regions. Individual SCNs were constructed using morphometric data from the Samsung Medical Center (SMC) dataset. The structural covariance connectivity showed higher clustering than randomly generated networks, as well as similar minimum path lengths, indicating that the SCNs are "small world." There were significant difference between NC and AD group in characteristic path lengths (z = -2.97, p < 0.01) and small-worldness values (z = 4.05, p < 0.01). Clustering coefficients in AD was smaller than that of NC but there was no significant difference (z = 1.81, not significant). We further observed that the AD patients had significantly disrupted structural connectivity. We also show that the coordinated variance of cortical thickness is distributed more randomly from one region to other regions in AD patients when compared to NC subjects. Our proposed SCN may provide surface-based measures for understanding interaction between two brain regions with co-atrophy of the cerebral cortex due to normal aging or AD. We applied our method to the AD Neuroimaging Initiative (ADNI) data to show consistency in results with the SMC

  3. Using Individualized Brain Network for Analyzing Structural Covariance of the Cerebral Cortex in Alzheimer's Patients.

    Science.gov (United States)

    Kim, Hee-Jong; Shin, Jeong-Hyeon; Han, Cheol E; Kim, Hee Jin; Na, Duk L; Seo, Sang Won; Seong, Joon-Kyung

    2016-01-01

    Cortical thinning patterns in Alzheimer's disease (AD) have been widely reported through conventional regional analysis. In addition, the coordinated variance of cortical thickness in different brain regions has been investigated both at the individual and group network levels. In this study, we aim to investigate network architectural characteristics of a structural covariance network (SCN) in AD, and further to show that the structural covariance connectivity becomes disorganized across the brain regions in AD, while the normal control (NC) subjects maintain more clustered and consistent coordination in cortical atrophy variations. We generated SCNs directly from T1-weighted MR images of individual patients using surface-based cortical thickness data, with structural connectivity defined as similarity in cortical thickness within different brain regions. Individual SCNs were constructed using morphometric data from the Samsung Medical Center (SMC) dataset. The structural covariance connectivity showed higher clustering than randomly generated networks, as well as similar minimum path lengths, indicating that the SCNs are "small world." There were significant difference between NC and AD group in characteristic path lengths (z = -2.97, p < 0.01) and small-worldness values (z = 4.05, p < 0.01). Clustering coefficients in AD was smaller than that of NC but there was no significant difference (z = 1.81, not significant). We further observed that the AD patients had significantly disrupted structural connectivity. We also show that the coordinated variance of cortical thickness is distributed more randomly from one region to other regions in AD patients when compared to NC subjects. Our proposed SCN may provide surface-based measures for understanding interaction between two brain regions with co-atrophy of the cerebral cortex due to normal aging or AD. We applied our method to the AD Neuroimaging Initiative (ADNI) data to show consistency in results with the SMC

  4. Avalanche analysis from multi-electrode ensemble recordings in cat, monkey and human cerebral cortex during wakefulness and sleep.

    Directory of Open Access Journals (Sweden)

    Nima eDehghani

    2012-08-01

    Full Text Available Self-organized critical states are found in many natural systems, from earthquakes to forest fires, they have also been observed in neural systems, particularly, in neuronal cultures. However, the presence of critical states in the awake brain remains controversial. Here, we compared avalanche analyses performed on different in vivo preparations during wakefulness, slow-wave sleep and REM sleep, using high-density electrode arrays in cat motor cortex (96 electrodes, monkey motor cortex and premotor cortex and human temporal cortex (96 electrodes in epileptic patients. In neuronal avalanches defined from units (up to 160 single units, the size of avalanches never clearly scaled as power-law, but rather scaled exponentially or displayed intermediate scaling. We also analyzed the dynamics of local field potentials (LFPs and in particular LFP negative peaks (nLFPs among the different electrodes (up to 96 sites in temporal cortex or up to 128 sites in adjacent motor and pre-motor cortices. In this case, the avalanches defined from nLFPs displayed power-law scaling in double logarithmic representations, as reported previously in monkey. However, avalanche defined as positive LFP (pLFP peaks, which are less directly related to neuronal firing, also displayed apparent power-law scaling. Closer examination of this scaling using the more reliable cumulative distribution function (CDF and other rigorous statistical measures, did not confirm power-law scaling. The same pattern was seen for cats, monkey and human, as well as for different brain states of wakefulness and sleep. We also tested other alternative distributions. Multiple exponential fitting yielded optimal fits of the avalanche dynamics with bi-exponential distributions. Collectively, these results show no clear evidence for power-law scaling or self-organized critical states in the awake and sleeping brain of mammals, from cat to man.

  5. Association of Cerebral Amyloidosis, Blood Pressure, and Neuronal Injury with Late-Life Onset Depression

    Science.gov (United States)

    Byun, Min Soo; Choe, Young Min; Sohn, Bo Kyung; Yi, Dahyun; Han, Ji Young; Park, Jinsick; Choi, Hyo Jung; Baek, Hyewon; Lee, Jun Ho; Kim, Hyun Jung; Kim, Yu Kyeong; Yoon, Eun Jin; Sohn, Chul-Ho; Woo, Jong Inn; Lee, Dong Young

    2016-01-01

    Previous literature suggests that Alzheimer's disease (AD) process may contribute to late-life onset depression (LLOD). Therefore, we investigated the association of LLOD with cerebral amyloidosis and neuronal injury, the two key brain changes in AD, along with vascular risks. Twenty nine non-demented individuals who first experienced major depressive disorder (MDD) after age of 60 years were included as LLOD subjects, and 27 non-demented elderly individuals without lifetime experience of MDD were included as normal controls (NC). Comorbid mild cognitive impairment (MCI) was diagnosed in 48% of LLOD subjects and in 0% of NC. LLOD, irrespective of comorbid MCI diagnosis, was associated with prominent prefrontal cortical atrophy. Compared to NC, LLOD subjects with comorbid MCI (LLODMCI) showed increased cerebral 11C-Pittsburg compound B (PiB) retention and plasma beta-amyloid 1–40 and 1–42 peptides, as measures of cerebral amyloidosis; and, such relationship was not observed in overall LLOD or LLOD without MCI (LLODwoMCI). LLOD subjects, particularly the LLODwoMCI, had higher systolic blood pressure (SBP) than NC. When analyzed in the same multiple logistic regression model that included prefrontal gray matter (GM) density, cerebral amyloidosis, and SBP as independent variables, only prefrontal GM density showed a significant independent association with LLOD regardless of MCI comorbidity status. Our findings suggest AD process might be related to LLOD via prefrontal neuronal injury in the MCI stage, whereas vascular processes—SBP elevation, in particular—are associated with LLOD via prefrontal neuronal injury even in cognitively intact or less impaired individuals. PMID:27790137

  6. Single neurons in M1 and premotor cortex directly reflect behavioral interference.

    Directory of Open Access Journals (Sweden)

    Neta Zach

    Full Text Available Some motor tasks, if learned together, interfere with each other's consolidation and subsequent retention, whereas other tasks do not. Interfering tasks are said to employ the same internal model whereas noninterfering tasks use different models. The division of function among internal models, as well as their possible neural substrates, are not well understood. To investigate these questions, we compared responses of single cells in the primary motor cortex and premotor cortex of primates to interfering and noninterfering tasks. The interfering tasks were visuomotor rotation followed by opposing visuomotor rotation. The noninterfering tasks were visuomotor rotation followed by an arbitrary association task. Learning two noninterfering tasks led to the simultaneous formation of neural activity typical of both tasks, at the level of single neurons. In contrast, and in accordance with behavioral results, after learning two interfering tasks, only the second task was successfully reflected in motor cortical single cell activity. These results support the hypothesis that the representational capacity of motor cortical cells is the basis of behavioral interference and division between internal models.

  7. Ultrastructure of focal cerebral cortex tissue from rats with focal cortical dysplasia

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    for observing its ultrastructure under a transmission electron microscope. MAIN OUTCOME MEASURES:①The ultrastructure of hippocampal tissue.②The conscious state and electrical activity of brain of rats. RESULTS:Eighteen rats were enrolled in the final analysis.① Observation of hippocampal ultrastructure: Electromicroscopic pathological findings showed that for each rat of the liquid nitrogen injured group, mitochondrium in the pyramidal neuron around the microgyrus was swelled,endoplasmic reticulum was expanded,glial cells were swelled,water gathered around the blood capillary,partial medullary sheath was degenerated,neuropilem was normal and no obviously abnormal synapse was found.② Changes in conscious state of rats:Rats in the normal control group and sham-operation group had no convulsive seizure, but those in the liquid nitrogen injured group had occasionally.Most of them showed increased activities, excitation and restlessness,scratching and frequent " watching face-like activities".③Electrical activity of brain of rats:Electroencephalogram recording of liquid nitrogen injured group showed that small wave amplitude of rhythm took the main part.No typical sharp wave,V wave,sharp and slow wave,V and slow waves were discharged. CONCLUSION:Liquid nitrogen can lead to cerebral cortical developmental disorder.Pathological changes of ultrastructure of focal tissue around the microgyrus can provide pathological basis for epilepsy associated with focal cortical developmental disorder.

  8. Protective effect and its mechanism of curcumin on ischemia-reperfusion injury of cerebral cortex in rats

    OpenAIRE

    Liu, Li; Bo-tao TAN; Li, Yu; Yu, Gang

    2013-01-01

    Objective  To investigate the effect of curcumin pretreatment on the expression of uncoupling protein 2 (UCP2) and mitochondrial transcription factor A (MTFA) in rats' cerebral cortex against focal ischemia reperfusion injury. Methods  Eighty male SD rats weighed 220g–300g were randomly divided into 4 groups: sham-operated group, ischemia/reperfusion (I/R) group, curcumine 50mg/kg+I/R (low dose) group, and curcumine 100mg/kg+I/R (high dose) group. The common carotid artery, external carotid a...

  9. Voluntary exercise prior to traumatic brain injury alters miRNA expression in the injured mouse cerebral cortex

    OpenAIRE

    Miao, W.; T.H. Bao; Han, J. H.; Yin, M.; Yan, Y.; Wang, W. W.; Zhu, Y. H.

    2015-01-01

    MicroRNAs (miRNAs) may be important mediators of the profound molecular and cellular changes that occur after traumatic brain injury (TBI). However, the changes and possible roles of miRNAs induced by voluntary exercise prior to TBI are still not known. In this report, the microarray method was used to demonstrate alterations in miRNA expression levels in the cerebral cortex of TBI mice that were pretrained on a running wheel (RW). Voluntary RW exercise prior to TBI: i) significantly decrease...

  10. A phosphatidylinositol lipids system, lamellipodin, and Ena/VASP regulate dynamic morphology of multipolar migrating cells in the developing cerebral cortex.

    Science.gov (United States)

    Yoshinaga, Satoshi; Ohkubo, Takahiro; Sasaki, Shinji; Nuriya, Mutsuo; Ogawa, Yukino; Yasui, Masato; Tabata, Hidenori; Nakajima, Kazunori

    2012-08-22

    In the developing mammalian cerebral cortex, excitatory neurons are generated in the ventricular zone (VZ) and subventricular zone; these neurons migrate toward the pial surface. The neurons generated in the VZ assume a multipolar morphology and remain in a narrow region called the multipolar cell accumulation zone (MAZ) for ∼24 h, in which they extend and retract multiple processes dynamically. They eventually extend an axon tangentially and begin radial migration using a migratory mode called locomotion. Despite the potential biological importance of the process movement of multipolar cells, the molecular mechanisms remain to be elucidated. Here, we observed that the processes of mouse multipolar cells were actin rich and morphologically resembled the filopodia and lamellipodia in growth cones; thus, we focused on the actin-remodeling proteins Lamellipodin (Lpd) and Ena/vasodilator-stimulated phosphoprotein (VASP). Lpd binds to phosphatidylinositol (3,4)-bisphosphate [PI(3,4)P₂] and recruits Ena/VASP, which promotes the assembly of actin filaments, to the plasma membranes. In situ hybridization and immunohistochemistry revealed that Lpd is expressed in multipolar cells in the MAZ. The functional silencing of either Lpd or Ena/VASP decreased the number of primary processes. Immunostaining and a Förster resonance energy transfer analysis revealed the subcellular localization of PI(3,4)P₂ at the tips of the processes. A knockdown experiment and treatment with an inhibitor for Src homology 2-containing inositol phosphatase-2, a 5-phosphatase that produces PI(3,4)P₂ from phosphatidylinositol (3,4,5)-triphosphate, decreased the number of primary processes. Our observations suggest that PI(3,4)P₂, Lpd, and Ena/VASP are involved in the process movement of multipolar migrating cells.

  11. NK-3 receptor activation depolarizes and induces an after-depolarization in pyramidal neurons in gerbil cingulate cortex

    DEFF Research Database (Denmark)

    Rekling, Jens C

    2004-01-01

    The involvement of tachykinins in cortical function is poorly understood. To study the actions of neurokinin-3 (NK3) receptor activation in frontal cortex, whole cell patch clamp recordings were performed from pyramidal neurons in slices of cingulate cortex from juvenile gerbils. Senktide (500n......M), a selective NK3 receptor agonist, induced a transient increase in spontaneous EPSPs in layer V pyramidal neurons, accompanied by a small depolarization ( approximately 4 mV). EPSPs during senktide had a larger amplitude and faster 10-90% rise time than during control. Senktide induced a transient...... depolarization in layer II/III pyramidal neurons, which often reached threshold for spikes. The depolarization ( approximately 6 mV) persisted in TTX, and was accompanied by an increase in input resistance. Senktide also transiently induced a slow after-depolarization, which appeared following a depolarizing...

  12. Effects of chronic ethanol exposure on neuronal function in the prefrontal cortex and extended amygdala.

    Science.gov (United States)

    Pleil, Kristen E; Lowery-Gionta, Emily G; Crowley, Nicole A; Li, Chia; Marcinkiewcz, Catherine A; Rose, Jamie H; McCall, Nora M; Maldonado-Devincci, Antoniette M; Morrow, A Leslie; Jones, Sara R; Kash, Thomas L

    2015-12-01

    Chronic alcohol consumption and withdrawal leads to anxiety, escalated alcohol drinking behavior, and alcohol dependence. Alterations in the function of key structures within the cortico-limbic neural circuit have been implicated in underlying the negative behavioral consequences of chronic alcohol exposure in both humans and rodents. Here, we used chronic intermittent ethanol vapor exposure (CIE) in male C57BL/6J mice to evaluate the effects of chronic alcohol exposure and withdrawal on anxiety-like behavior and basal synaptic function and neuronal excitability in prefrontal cortical and extended amygdala brain regions. Forty-eight hours after four cycles of CIE, mice were either assayed in the marble burying test (MBT) or their brains were harvested and whole-cell electrophysiological recordings were performed in the prelimbic and infralimbic medial prefrontal cortex (PLC and ILC), the lateral and medial central nucleus of the amygdala (lCeA and mCeA), and the dorsal and ventral bed nucleus of the stria terminalis (dBNST and vBNST). Ethanol-exposed mice displayed increased anxiety in the MBT compared to air-exposed controls, and alterations in neuronal function were observed in all brain structures examined, including several distinct differences between subregions within each structure. Chronic ethanol exposure induced hyperexcitability of the ILC, as well as a shift toward excitation in synaptic drive and hyperexcitability of vBNST neurons; in contrast, there was a net inhibition of the CeA. This study reveals extensive effects of chronic ethanol exposure on the basal function of cortico-limbic brain regions, suggests that there may be complex interactions between these regions in the regulation of ethanol-dependent alterations in anxiety state, and highlights the need for future examination of projection-specific effects of ethanol in cortico-limbic circuitry.

  13. Effects of chronic ethanol exposure on neuronal function in the prefrontal cortex and extended amygdala.

    Science.gov (United States)

    Pleil, Kristen E; Lowery-Gionta, Emily G; Crowley, Nicole A; Li, Chia; Marcinkiewcz, Catherine A; Rose, Jamie H; McCall, Nora M; Maldonado-Devincci, Antoniette M; Morrow, A Leslie; Jones, Sara R; Kash, Thomas L

    2015-12-01

    Chronic alcohol consumption and withdrawal leads to anxiety, escalated alcohol drinking behavior, and alcohol dependence. Alterations in the function of key structures within the cortico-limbic neural circuit have been implicated in underlying the negative behavioral consequences of chronic alcohol exposure in both humans and rodents. Here, we used chronic intermittent ethanol vapor exposure (CIE) in male C57BL/6J mice to evaluate the effects of chronic alcohol exposure and withdrawal on anxiety-like behavior and basal synaptic function and neuronal excitability in prefrontal cortical and extended amygdala brain regions. Forty-eight hours after four cycles of CIE, mice were either assayed in the marble burying test (MBT) or their brains were harvested and whole-cell electrophysiological recordings were performed in the prelimbic and infralimbic medial prefrontal cortex (PLC and ILC), the lateral and medial central nucleus of the amygdala (lCeA and mCeA), and the dorsal and ventral bed nucleus of the stria terminalis (dBNST and vBNST). Ethanol-exposed mice displayed increased anxiety in the MBT compared to air-exposed controls, and alterations in neuronal function were observed in all brain structures examined, including several distinct differences between subregions within each structure. Chronic ethanol exposure induced hyperexcitability of the ILC, as well as a shift toward excitation in synaptic drive and hyperexcitability of vBNST neurons; in contrast, there was a net inhibition of the CeA. This study reveals extensive effects of chronic ethanol exposure on the basal function of cortico-limbic brain regions, suggests that there may be complex interactions between these regions in the regulation of ethanol-dependent alterations in anxiety state, and highlights the need for future examination of projection-specific effects of ethanol in cortico-limbic circuitry. PMID:26188147

  14. Automated identification of neurons and their locations

    OpenAIRE

    Inglis, A.; Cruz, L; Roe, D L; H. E. Stanley; Rosene, D.L.; Urbanc, B.

    2008-01-01

    Individual locations of many neuronal cell bodies (>10^4) are needed to enable statistically significant measurements of spatial organization within the brain such as nearest-neighbor and microcolumnarity measurements. In this paper, we introduce an Automated Neuron Recognition Algorithm (ANRA) which obtains the (x,y) location of individual neurons within digitized images of Nissl-stained, 30 micron thick, frozen sections of the cerebral cortex of the Rhesus monkey. Identification of neurons ...

  15. Differential visually-induced gamma-oscillations in human cerebral cortex

    OpenAIRE

    Asano, Eishi; Nishida, Masaaki; Fukuda, Miho; Rothermel, Robert; Juhasz, Csaba; Sood, Sandeep

    2008-01-01

    Using intracranial electrocorticography, we determined how cortical gamma-oscillations (50–150Hz) were induced by different visual tasks in nine children with focal epilepsy. In all children, full-field stroboscopic flash-stimuli induced gamma-augmentation in the anterior-medial occipital cortex (starting on average at 31-msec after stimulus presentation) and subsequently in the lateral-polar occipital cortex; minimal gamma-augmentation was noted in the inferior occipital-temporal cortex; occ...

  16. Neuronal Development: SAD Kinases Make Happy Axons

    OpenAIRE

    Xing, Lei; Newbern, Jason M.; Snider, William D

    2013-01-01

    The polarity proteins LKB1 and SAD-A/B are key regulators of axon specification in the developing cerebral cortex. Recent studies now show that this mechanism cannot be generalized to other classes of neurons: instead, SAD-A/B functions downstream of neurotrophin signaling in sensory neurons to mediate a later stage of axon development — arborization in the target field.

  17. Coordinated scaling of cortical and cerebellar numbers of neurons

    Directory of Open Access Journals (Sweden)

    Suzana Herculano-Houzel

    2010-03-01

    Full Text Available While larger brains possess concertedly larger cerebral cortices and cerebella, the relative size of the cerebral cortex increases with brain size, but relative cerebellar size does not. In the absence of data on numbers of neurons in these structures, this discrepancy has been used to dispute the hypothesis that the cerebral cortex and cerebellum function and have evolved in concert and to support a trend towards neocorticalization in evolution. However, the rationale for interpreting changes in absolute and relative size of the cerebral cortex and cerebellum relies on the assumption that they reflect absolute and relative numbers of neurons in these structures across all species – an assumption that our recent studies have shown to be flawed. Here I show for the first time that the numbers of neurons in the cerebral cortex and cerebellum are directly correlated across 19 mammalian species of 4 different orders, including humans, and increase concertedly in a similar fashion both within and across the orders Eulipotyphla (Insectivora, Rodentia, Scandentia and Primata, such that on average a ratio of 3.6 neurons in the cerebellum to every neuron in the cerebral cortex is maintained across species. This coordinated scaling of cortical and cerebellar numbers of neurons provides direct evidence in favor of concerted function, scaling and evolution of these brain structures, and suggests that the common notion that equates cognitive advancement with neocortical expansion should be revisited to consider in its stead the coordinated scaling of neocortex and cerebellum as a functional ensemble.

  18. Neuronal apoptosis, metallothionein expression and proinflammatory responses during cerebral malaria in mice

    DEFF Research Database (Denmark)

    Wiese, Lothar; Kurtzhals, Jørgen A L; Penkowa, Milena

    2006-01-01

    BACKGROUND: Cerebral malaria (CM) is an acute encephalopathy in humans due to the infection with Plasmodium falciparum. Neuro-cognitive impairment following CM occurs in about 10% of the treated survivors, while the precise pathophysiological mechanism remains unknown. Metallothionein I + II (MT...... show: (1) a localized CM-induced neuronal apoptosis (detected by TUNEL) indicating severe and irreversible pathology. (2) A significant increase in MT-I + II expression in reactive astrocytes, macrophages/microglia and vascular endothelium. INTERPRETATION: This is the first report showing apoptosis...

  19. A pattern formed by preferential orientation of tangential fibres in layer I of the rabbit's cerebral cortex.

    Science.gov (United States)

    Fleischhauer, K; Laube, A

    1977-12-01

    1. The tangential organization of layer I has been studied in frozen sections impregnated according to a modified Liesegang method and in Bodian impregnated paraffin sections cut tangentially to the dorsal surface of the rabbit's cerebral cortex. 2. It is shown that sublamina tangentialis of layer I contains a system of parallel nerve fibres forming a distinct pattern in the tangential plane. 3. This pattern has been reconstructed for a large region of the dorsal surface of the cerebral cortex including the striate areas as well as the peristriate, parietal and precentral agranular regions and parts of the retrosplenial area. 4. In most parts of the region investigated, the tangential fibres of layer I are oriented in an antero-medial to postero-lateral direction, forming an angle of about 50 degrees with the sagittal plane. 5. Deviations from this pattern are found in the furrows formed by the lateral sulcus and the frontal impression and also in the caudal part of the retrosplenial area. In these regions, which are characterized by comparatively steep changes of the cortical relief, the fibres course in a more sagittal direction.

  20. A pattern formed by preferential orientation of tangential fibres in layer I of the rabbit's cerebral cortex.

    Science.gov (United States)

    Fleischhauer, K; Laube, A

    1977-12-01

    1. The tangential organization of layer I has been studied in frozen sections impregnated according to a modified Liesegang method and in Bodian impregnated paraffin sections cut tangentially to the dorsal surface of the rabbit's cerebral cortex. 2. It is shown that sublamina tangentialis of layer I contains a system of parallel nerve fibres forming a distinct pattern in the tangential plane. 3. This pattern has been reconstructed for a large region of the dorsal surface of the cerebral cortex including the striate areas as well as the peristriate, parietal and precentral agranular regions and parts of the retrosplenial area. 4. In most parts of the region investigated, the tangential fibres of layer I are oriented in an antero-medial to postero-lateral direction, forming an angle of about 50 degrees with the sagittal plane. 5. Deviations from this pattern are found in the furrows formed by the lateral sulcus and the frontal impression and also in the caudal part of the retrosplenial area. In these regions, which are characterized by comparatively steep changes of the cortical relief, the fibres course in a more sagittal direction. PMID:603078

  1. Acute Carnosine Administration Increases Respiratory Chain Complexes and Citric Acid Cycle Enzyme Activities in Cerebral Cortex of Young Rats.

    Science.gov (United States)

    Macedo, Levy W; Cararo, José H; Maravai, Soliany G; Gonçalves, Cinara L; Oliveira, Giovanna M T; Kist, Luiza W; Guerra Martinez, Camila; Kurtenbach, Eleonora; Bogo, Maurício R; Hipkiss, Alan R; Streck, Emilio L; Schuck, Patrícia F; Ferreira, Gustavo C

    2016-10-01

    Carnosine (β-alanyl-L-histidine) is an imidazole dipeptide synthesized in excitable tissues of many animals, whose biochemical properties include carbonyl scavenger, anti-oxidant, bivalent metal ion chelator, proton buffer, and immunomodulating agent, although its precise physiological role(s) in skeletal muscle and brain tissues in vivo remain unclear. The aim of the present study was to investigate the in vivo effects of acute carnosine administration on various aspects of brain bioenergetics of young Wistar rats. The activity of mitochondrial enzymes in cerebral cortex was assessed using a spectrophotometer, and it was found that there was an increase in the activities of complexes I-III and II-III and succinate dehydrogenase in carnosine-treated rats, as compared to vehicle-treated animals. However, quantitative real-time RT-PCR (RT-qPCR) data on mRNA levels of mitochondrial biogenesis-related proteins (nuclear respiratory factor 1 (Nrf1), peroxisome proliferator-activated receptor-γ coactivator 1-α (Ppargc1α), and mitochondrial transcription factor A (Tfam)) were not altered significantly and therefore suggest that short-term carnosine administration does not affect mitochondrial biogenesis. It was in agreement with the finding that immunocontent of respiratory chain complexes was not altered in animals receiving carnosine. These observations indicate that acute carnosine administration increases the respiratory chain and citric acid cycle enzyme activities in cerebral cortex of young rats, substantiating, at least in part, a neuroprotector effect assigned to carnosine against oxidative-driven disorders.

  2. Characteristics of intracellularly injected infragranular pyramidal neurons in cat primary auditory cortex.

    Science.gov (United States)

    Ojima, H; Honda, C N; Jones, E G

    1992-01-01

    Pyramidal neurons in layers V and VI of cat primary auditory cortex (AI) were intracellularly injected with biocytin after functional characterization according to a position relative to an anteroposterior sequence of best-frequency responses. A sample of 19 completely filled neurons was analyzed, and a preliminary classification was made on the basis of dendritic morphology and axon collateral distribution. Layer V cells could be divided into two types. Cells in the upper part of layer V and projecting toward the diencephalon had a large cell body and an apical dendrite with extensive branches in layer I. These cells had few recurrent axon collaterals, and no terminal axonal bushes were formed in the vicinity of the dendritic field. Long horizontal collaterals with many boutons, however, extended in various directions parallel to the cortical surface. By contrast, cells in the lower part of layer V and sending an axon into the putamen, or without an obvious subcortical axon, had a medium soma and an apical dendrite with few branches in layer I. These cells had a dense bush of recurrent collaterals extending into layers II and III and surrounding the dendritic field, but few or no horizontal collaterals. Layer VI injected neurons were more heterogeneous. All had a thin ascending dendrite with oblique branches both ending in layer III. Axon collateral distributions varied from cell to cell. Relatively small cells with an apical dendrite that branched frequently in layers III and IV had a dense network of recurrent collaterals in the dendritic field, but virtually no horizontal collaterals. This type projected toward the diencephalon. Cells with relatively long horizontal collaterals and a weak recurrent system confined to layers V and VI had a unique arborization pattern of basal dendrites. This type may have projected to the claustrum or other cortical areas. One cell with dendritic branches restricted to layer VI had horizontal collaterals predominantly in layer

  3. Reactive changes in astrocytes, and delayed neuronal death, in the rat hippocampal CA1 region following cerebral ischemia/reperfusion

    Institute of Scientific and Technical Information of China (English)

    Guiqing Zhang; Xiang Luo; Zhiyuan Yu; Chao Ma; Shabei Xu; Wei Wang

    2009-01-01

    BACKGROUND: Blood supply to the hippocampus is not provided by the middle cerebral artery. However, previous studies have shown that delayed neuronal death in the hippocampus may occur following focal cerebral ischemia induced by middle cerebral artery occlusion. OBJECTIVE: To observe the relationship between reactive changes in hippocampal astrocytes and delayed neuronal death in the hippocampal CA1 region following middle cerebral artery occlusion. DESIGN, TIME AND SETTING: The immunohistochemical, randomized, controlled animal study was performed at the Laboratory of Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, from July to November 2007. MATERIALS: Rabbit anti-glial fibrillary acidic protein (GFAP) (Neomarkers, USA), goat anti-rabbit IgG (Sigma, USA) and ApoAlert apoptosis detection kit (Biosciences Clontech, USA) were used in this study. METHODS: A total of 42 healthy adult male Wistar rats, aged 3-5 months, were randomly divided into a sham operation group (n = 6) and a cerebral ischemia/reperfusion group (n = 36). In the cerebral ischemia/reperfusion group, cerebral ischemia/reperfusion models were created by middle cerebral artery occlusion. In the sham operation group, the thread was only inserted into the initial region of the internal carotid artery, and middle cerebral artery occlusion was not induced. Rats in the cerebral ischemia/reperfusion group were assigned to a delayed neuronal death (+) subgroup and a delayed neuronal death (-) subgroup, according to the occurrence of delayed neuronal death in the ischemic side of the hippocampal CA1 region following cerebral ischemia. MAIN OUTCOME MEASURES: Delayed neuronal death in the hippocampal CA1 region was measured by Nissl staining. GFAP expression and delayed neuronal death changes were measured in the rat hippocampal CA1 region at the ischemic hemisphere by double staining for GFAP and TUNEL. RESULTS: After 3 days of ischemia

  4. The contribution of CXCL12-expressing radial glia cells to neuro-vascular patterning during human cerebral cortex development

    Directory of Open Access Journals (Sweden)

    Mariella eErrede

    2014-10-01

    Full Text Available This study was conducted on human developing brain by laser confocal and transmission electron microscopy to make a detailed analysis of important features of blood-brain barrier microvessels and possible control mechanisms of vessel growth and differentiation during cerebral cortex vascularization. The blood-brain barrier status of cortex microvessels was examined at a defined stage of cortex development, at the end of neuroblast waves of migration and before cortex lamination, with blood-brain barrier-endothelial cell markers, namely tight junction proteins (occludin and claudin-5 and influx and efflux transporters (Glut-1 and P-glycoprotein, the latter supporting evidence for functional effectiveness of the fetal blood-brain barrier. According to the well-known roles of astroglia cells on microvessel growth and differentiation, the early composition of astroglia/endothelial cell relationships was analysed by detecting the appropriate astroglia, endothelial, and pericyte markers. GFAP, chemokine CXCL12, and connexin 43 (Cx43 were utilized as markers of radial glia cells, CD105 (endoglin as a marker of angiogenically activated endothelial cells, and proteoglycan NG2 as a marker of immature pericytes. Immunolabeling for CXCL12 showed the highest level of the ligand in radial glial fibres in contact with the growing cortex microvessels. These specialized contacts, recognizable on both perforating radial vessels and growing collaterals, appeared as CXCL12-reactive en passant, symmetrical and asymmetrical vessel-specific RG fibre swellings. At the highest confocal resolution, these RG varicosities showed a CXCL12-reactive dot-like content whose microvesicular nature was confirmed by ultrastructural observations. A further analysis of radial glial varicosities reveals colocalization of CXCL12 with connexin Cx43, which is possibly implicated in vessel-specific chemokine signalling.

  5. Mirrored patterns of lateralized neuronal activation reflect old and new memories in the avian auditory cortex.

    Science.gov (United States)

    Olson, Elizabeth M; Maeda, Rie K; Gobes, Sharon M H

    2016-08-25

    In monolingual humans, language-related brain activation shows a distinct lateralized pattern, in which the left hemisphere is often dominant. Studies are not as conclusive regarding the localization of the underlying neural substrate for language in sequential language learners. Lateralization of the neural substrate for first and second language depends on a number of factors including proficiency and early experience with each language. Similar to humans learning speech, songbirds learn their vocalizations from a conspecific tutor early in development. Here, we show mirrored patterns of lateralization in the avian analog of the mammalian auditory cortex (the caudomedial nidopallium [NCM]) in sequentially tutored zebra finches (Taeniopygia guttata​) in response to their first tutor song, learned early in development, and their second tutor song, learned later in development. The greater the retention of song from their first tutor, the more right-dominant the birds were when exposed to that song; the more birds learned from their second tutor, the more left-dominant they were when exposed to that song. Thus, the avian auditory cortex may preserve lateralized neuronal traces of old and new tutor song memories, which are dependent on proficiency of song learning. There is striking resemblance in humans: early-formed language representations are maintained in the brain even if exposure to that language is discontinued. The switching of hemispheric dominance related to the acquisition of early auditory memories and subsequent encoding of more recent memories may be an evolutionary adaptation in vocal learners necessary for the behavioral flexibility to acquire novel vocalizations, such as a second language. PMID:27288718

  6. EFFECT OF MELATONIN AGAINST GLUTAMATE-INDUCED EXCITOTOXICITY ON CULTURED CEREBRAL CORTICAL NEURONS

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective To research the effect of melatonin against glutamate excitotoxicity. Methods The model of glutamate-induced excitotoxic damage was built up in rat cerebral cortical cell culture. The effect of mela- tonin against excitotoxic injury was observed by determining the leakage rate of lactate dehydrogenase(LDH) from neurons. Results The leakage rate of LDH wasn't decreased markedly when cultures were exposed to melatonin be- fore, during or 6 h after glutamate treatment. The leakage rate of LDH was decreased significantly when melatonin was administered 0 h, 2 h or 4 h after the cultures were exposed to glutamate. The inhibitory function of melatonin on LDH leakage was most effective at 2 h and 4 h. Conclusion Melatonin has protective effects on neurons damaged by glutamate in a certain time limit.

  7. Ultrastructural Study of Neuronal Death in Rat Hippocampus after Transient and Permanent Focal Cerebral Ischemia

    Directory of Open Access Journals (Sweden)

    Majid Asadi-Shekaari

    2009-01-01

    Full Text Available Objective: Morphological changes of CA1 neurons in rat hippocampus after transientand permanent focal cerebral ischemia were studied to clarify the nature of postischemiccell death in the subfield.Materials and Methods: Male adult rats were divided into 3 groups: Control (Shamoperated,transient ischemic group (30 minutes of MCAO followed by 48 hours ofreperfusion, and permanent ischemic group (48 hours of MCAO. After the mentionedtimes, deep anesthesia was induced in the rats and their brains were removed andprocessed for transmission electron microscopy (TEM and evaluation.Results: Electron-microscopic examination on day 2 showed key morphological signsof apoptosis in the permanent ischemic group, while morphological signs of necrosiswere observed in the transient ischemic group.Conclusion: These results suggest necrosis (as dominant mechanism of neuronaldeath after transient ischemia and apoptosis (after permanent ischemia to be involvedin neuronal death.

  8. Patterns of axon collateralization of identified supragranular pyramidal neurons in the cat auditory cortex.

    Science.gov (United States)

    Ojima, H; Honda, C N; Jones, E G

    1991-01-01

    Nine pyramidal neurons in layers II and III of cat primary auditory cortex (AI) were fully reconstructed after intracellular injections of horseradish peroxidase or biocytin. Each neuron was functionally characterized according to its position relative to an anteroposterior sequence of best frequency responses. All labeled somata were in layers II or III and gave rise to typical apical and basal dendritic arbors as well as to extensive systems of axon collaterals. The primary axon of all except 1 cell entered the white matter and was probably directed toward other cortical areas ipsi- or contralaterally. Two major intracortical collateral systems emerged from the main axon in AI, one ending in the vicinity of the cell and the second at a distance. (1) Many local and recurrent collaterals, given off in layers III and V, contributed terminal branches to the formation of a columnar pattern of terminations extending superficially and deeply into the soma. The column extended through layers I-V, with some constriction in the middle portion corresponding to layer IV. (2) The axon of each cell also gave rise to 2-5 thick, long-range collaterals in layers III and/or V. These ran parallel to the pial surface for several millimeters. At several points along these long horizontal collaterals, vertically directed branches emerged to form columnar terminations, again extending through layers I-V. These columns did not overlap with that formed in the vicinity of the cell, and were situated at distances 500-1200 microns from the cell body. When viewed in the tangential plane, horizontal collaterals were oriented, on the whole, dorsoventrally with respect to the surface of the cortex. This may correspond to the organization of isofrequency bands previously described in cats. The results suggest that the major spread of excitation in AI is mediated by horizontal collaterals of pyramidal cells and that it occurs along the lines of isofrequency domains. Within the latter the

  9. THE EFFECT OF LIGUSTRAZINE ON NEUROGENESIS IN CORTEX AFTER FOCAL CEREBRAL ISCHEMIA IN RATS

    Institute of Scientific and Technical Information of China (English)

    邱芬; 刘勇; 张蓬勃; 康前雁; 田英芳; 陈新林; 赵建军; 祁存芳

    2006-01-01

    It has been demonstrated that there are neuralstemcells that can self-renewand differentiate intomultiple cell types[1-3]in central nervous system ofadult mammals.After cerebral ischemia,these cellscan proliferate,migrate,differentiate and partici-pate in the repair of ischemic cerebral injuries[4-6].Neural stemcells play a very i mportant role in alle-viating ischemic cerebral injuries and promotingfunctional recovery.Ligustrazine,an active ingre-dient of Ligustici,can help dilate blood vessels,i m-prove m...

  10. Spatio-temporal characteristics of cerebral blood volume changes in different microvascular compartments evoked by sciatic nerve stimulation in rat somatosensory cortex

    Science.gov (United States)

    Li, Pengcheng; Luo, Qingming; Luo, Weihua; Chen, Shangbin; Chen, Haiying; Zeng, Shaoqun

    2003-10-01

    The spatio-temporal characteristics of changes in cerebral blood volume associated with neuronal activity were investigated in the hindlimb somatosensory cortex of α-chloralose/urethan anesthetized rats (n=10) with optical imaging at 570nm through a thinned skull. Activation of cortex was carried out by electrical stimulation of the contralateral sciatic nerve with 5Hz, 0.3V pulses (0.5ms) for duration of 2s. The stimulation evoked a monophasic optical reflectance decrease at cortical parenchyma and arteries sites rapidly after the onset of stimulation, whereas no similar response was observed at vein compartments. The optical signal changes reached 10% of the peak response 0.70+/-0.32s after stimulation onset and no significant time lag in this 10% start latency time was observed between the response at cortical parenchyma and arteries compartments. The evoked optical reflectance decrease reached the peak (0.25%+/-0.047%)2.66+/-0.61s after the stimulus onset at parenchyma site, 0.40+/-0.20s earlier (P<0.05) than that at arteries site (0.50%+/-0.068% 3.06+/-0.70s). Variable location within the cortical parenchyma and arteries compartment themselves didn"t affect the temporal characteristics of the evoked signal significantly. These results suggest that the sciatic nerve stimulation evokes a local blood volume increase at both capillaries (cortical parenchyma) and arterioles rapidly after the stimulus onset but the evoked blood volume increase in capillaries could not be entirely accounted for by the dilation of arterioles.

  11. A Laboratory Exercise Demonstrating the Limited Circumstances in which the Cerebral Cortex is Engaged in Over Ground Locomotion.

    Science.gov (United States)

    Buford, John A

    2005-01-01

    For neuroscience, memorable demonstrations of principles in action are crucial. Neural control of walking is particularly difficult to understand because the interaction of the cerebral cortex with a central pattern generator (CPG) makes the mode of control context-dependent. Beginning students tend to consider corticospinal control the basis of all movement, so they may not distinguish the limited circumstances in which the cerebral cortex bypasses the CPG to control leg movements directly for walking. The demonstration described here is designed to show that cortical involvement in normal walking is minimal unless visual control of foot placement is required. Cortical involvement in motor control is assessed by probing for spare attention while a student volunteer performs three different tasks: sitting, walking down a hallway, and walking through an obstacle course. Simple math quizzes with 20 oral questions are the probes. The class observes the demonstration and discusses the results. To evaluate learning, a multiple-choice question was administered two months after the demonstration, as well as 14 months later to cohorts from the previous year's class. The demonstration succeeded: quiz scores were similar for sitting and level walking, but lower for the obstacle course. Two months later, 86% of students correctly answered the multiple choice question; 42% of the previous year's cohorts answered correctly after 14 months. The demonstration shows that the cortex is engaged by walking through an obstacle course, not walking on a flat indoor surface. Initially, most students learned this distinction well, but after a year, many reverted to the idea that the corticospinal tract controls details of leg movements during walking. Thus this result emphasizes the need for review of advanced concepts. Overall, the experience was fun and could easily fit into basic or clinical neuroscience courses. PMID:23494163

  12. Neuronal activity related to eye-hand coordination in the primate premotor cortex.

    Science.gov (United States)

    Jouffrais, C; Boussaoud, D

    1999-09-01

    To test the functional implications of gaze signals that we previously reported in the dorsal premotor cortex (PMd), we trained two rhesus monkeys to point to visual targets presented on a touch screen while controlling their gaze orientation. Each monkey had to perform four different tasks. To initiate a trial, the monkey had to put his hand on a starting position at the center of the touch screen and fixate a fixation point. In one task, the animal had to make a reaching movement to a peripheral target randomly presented at one of eight possible locations on a circle while maintaining fixation at the center of this virtual circle (central fixation + reaching). In the second task, the monkey maintained fixation at the location of the upcoming peripheral target and, later, reached to that location. After a delay, the target was turned on and the monkey made a reaching arm movement (target fixation + reaching). In the third task, the monkey made a saccade to the target without any arm movement (saccade). Finally, in the fourth task, the monkey first made a saccade to the target, then reached to it after a delay (saccade + reaching). This design allowed us to examine the contribution of the oculomotor context to arm-related neuronal activity in PMd. We analyzed the effects of the task type on neuronal activity and found that many cells showed a task effect during the signal (26/60; 43%), set (16/49; 33%) and/or movement (15/54; 28%) epochs, depending on the oculomotor history. These findings, together with previously published data, suggest that PMd codes limb-movement direction in a gaze-dependent manner and may, thus, play an important role in the brain mechanisms of eye-hand coordination during visually guided reaching. PMID:10473760

  13. Reinforcement learning of targeted movement in a spiking neuronal model of motor cortex.

    Directory of Open Access Journals (Sweden)

    George L Chadderdon

    Full Text Available Sensorimotor control has traditionally been considered from a control theory perspective, without relation to neurobiology. In contrast, here we utilized a spiking-neuron model of motor cortex and trained it to perform a simple movement task, which consisted of rotating a single-joint "forearm" to a target. Learning was based on a reinforcement mechanism analogous to that of the dopamine system. This provided a global reward or punishment signal in response to decreasing or increasing distance from hand to target, respectively. Output was partially driven by Poisson motor babbling, creating stochastic movements that could then be shaped by learning. The virtual forearm consisted of a single segment rotated around an elbow joint, controlled by flexor and extensor muscles. The model consisted of 144 excitatory and 64 inhibitory event-based neurons, each with AMPA, NMDA, and GABA synapses. Proprioceptive cell input to this model encoded the 2 muscle lengths. Plasticity was only enabled in feedforward connections between input and output excitatory units, using spike-timing-dependent eligibility traces for synaptic credit or blame assignment. Learning resulted from a global 3-valued signal: reward (+1, no learning (0, or punishment (-1, corresponding to phasic increases, lack of change, or phasic decreases of dopaminergic cell firing, respectively. Successful learning only occurred when both reward and punishment were enabled. In this case, 5 target angles were learned successfully within 180 s of simulation time, with a median error of 8 degrees. Motor babbling allowed exploratory learning, but decreased the stability of the learned behavior, since the hand continued moving after reaching the target. Our model demonstrated that a global reinforcement signal, coupled with eligibility traces for synaptic plasticity, can train a spiking sensorimotor network to perform goal-directed motor behavior.

  14. Reinforcement learning of targeted movement in a spiking neuronal model of motor cortex.

    Science.gov (United States)

    Chadderdon, George L; Neymotin, Samuel A; Kerr, Cliff C; Lytton, William W

    2012-01-01

    Sensorimotor control has traditionally been considered from a control theory perspective, without relation to neurobiology. In contrast, here we utilized a spiking-neuron model of motor cortex and trained it to perform a simple movement task, which consisted of rotating a single-joint "forearm" to a target. Learning was based on a reinforcement mechanism analogous to that of the dopamine system. This provided a global reward or punishment signal in response to decreasing or increasing distance from hand to target, respectively. Output was partially driven by Poisson motor babbling, creating stochastic movements that could then be shaped by learning. The virtual forearm consisted of a single segment rotated around an elbow joint, controlled by flexor and extensor muscles. The model consisted of 144 excitatory and 64 inhibitory event-based neurons, each with AMPA, NMDA, and GABA synapses. Proprioceptive cell input to this model encoded the 2 muscle lengths. Plasticity was only enabled in feedforward connections between input and output excitatory units, using spike-timing-dependent eligibility traces for synaptic credit or blame assignment. Learning resulted from a global 3-valued signal: reward (+1), no learning (0), or punishment (-1), corresponding to phasic increases, lack of change, or phasic decreases of dopaminergic cell firing, respectively. Successful learning only occurred when both reward and punishment were enabled. In this case, 5 target angles were learned successfully within 180 s of simulation time, with a median error of 8 degrees. Motor babbling allowed exploratory learning, but decreased the stability of the learned behavior, since the hand continued moving after reaching the target. Our model demonstrated that a global reinforcement signal, coupled with eligibility traces for synaptic plasticity, can train a spiking sensorimotor network to perform goal-directed motor behavior.

  15. EFFECT OF VASOPRESSIN ON DELAYED NEURONAL DAMAGE IN HIPPOCAMPUS FOLLOWING CEREBRAL ISCHEMIA AND REPERFUSION IN GERBILS

    Institute of Scientific and Technical Information of China (English)

    刘新峰; 金泳清; 陈光辉

    1996-01-01

    Mongolian gerbils were used as delayed neuronal damage (DND) animal models.At the end of 15 minute cerebral ischermia and at various reperfusion time ranging from 1 to 96 hours,the content of water and arginine vasopressin (AVP) in the CA1 sector of hippocampus were measured by the specific gravity method and radioimmunoassy.Furthermore,we also examined the effect of intracerebroventricular (ICV) injection of AVP,AVP antiserum on calcium,Na+,K+-ATP ase activity in the CA1 sector after ischemia and 96 hour reperfusion.The results showed that AVP Contents of CA1 sector of hippocampus during 6 to 96 hour recirculation,and the water content of CA1 sector during 24 to 96 hour were significantly and continuously increased.After ICV injection of AVP,the water content and calcium in CA1 sector of hippocampus at cerebral ischemia and 96 hour recirculation further increased,and the Na+,K+-AT-tion of AVP antiserum,the water contenr and calcium in CA1 sector were significantly decreased as compared with that of control.These suggested that AVP was involved in the pathopysiologic process of DND in hippocampus following cerbral ischemia and reprfusion.Its mechanism might be through the change of intracellular action mediated by specific AVP receptor to lead to Ca inos over-load of neuron and inhibit the Na+,K+-ATPase activity,thereby to exacerbate the DND in hippocampus.

  16. Multichannel optical brain imaging to separate cerebral vascular, tissue metabolic, and neuronal effects of cocaine

    Science.gov (United States)

    Ren, Hugang; Luo, Zhongchi; Yuan, Zhijia; Pan, Yingtian; Du, Congwu

    2012-02-01

    Characterization of cerebral hemodynamic and oxygenation metabolic changes, as well neuronal function is of great importance to study of brain functions and the relevant brain disorders such as drug addiction. Compared with other neuroimaging modalities, optical imaging techniques have the potential for high spatiotemporal resolution and dissection of the changes in cerebral blood flow (CBF), blood volume (CBV), and hemoglobing oxygenation and intracellular Ca ([Ca2+]i), which serves as markers of vascular function, tissue metabolism and neuronal activity, respectively. Recently, we developed a multiwavelength imaging system and integrated it into a surgical microscope. Three LEDs of λ1=530nm, λ2=570nm and λ3=630nm were used for exciting [Ca2+]i fluorescence labeled by Rhod2 (AM) and sensitizing total hemoglobin (i.e., CBV), and deoxygenated-hemoglobin, whereas one LD of λ1=830nm was used for laser speckle imaging to form a CBF mapping of the brain. These light sources were time-sharing for illumination on the brain and synchronized with the exposure of CCD camera for multichannel images of the brain. Our animal studies indicated that this optical approach enabled simultaneous mapping of cocaine-induced changes in CBF, CBV and oxygenated- and deoxygenated hemoglobin as well as [Ca2+]i in the cortical brain. Its high spatiotemporal resolution (30μm, 10Hz) and large field of view (4x5 mm2) are advanced as a neuroimaging tool for brain functional study.

  17. Reelin-immunoreactive neurons in entorhinal cortex layer II selectively express intracellular amyloid in early Alzheimer's disease.

    Science.gov (United States)

    Kobro-Flatmoen, Asgeir; Nagelhus, Anne; Witter, Menno P

    2016-09-01

    The onset of Alzheimer's disease (AD) is associated with subtle pathological changes including increased intracellular expression of amyloid-β (Aβ). A structure affected particularly early in the course of AD is the entorhinal cortex, where neuronal death in layer II is observed already at initial stages. Neurons in EC-layer II, particularly those that express the protein Reelin, give rise to projections to the hippocampal dentate gyrus and this projection shows severe loss of synaptic contacts during early-stage AD. Given this anatomical specificity, we sought to determine whether increased intracellular expression of Aβ is selectively associated with Reelin-immunoreactive neurons in layer II of the entorhinal cortex. Here we report that in a transgenic rat model, which mimics the onset and distribution of extracellular amyloid deposits seen in human AD subjects, expression of intracellular Aβ in entorhinal layer II selectively occurs in Reelin-immunoreactive neurons during the early, pre-plaque stage. This Reelin-Aβ association is also present in human subjects with AD-related pathological changes, even in early disease stages. These findings strongly indicate that Reelin-immunoreactive neurons in entorhinal layer II play a crucial role during the initial stages of AD, and may therefore lead to refined hypotheses concerning the origin of this devastating condition. PMID:27195475

  18. Time course changes of NADPH-d positive neuron counts in the cortex of mice after heat stress

    Institute of Scientific and Technical Information of China (English)

    Yan Wang; Ling Chen; Yu-Zhong Jin

    2016-01-01

    Objective:To discuss the time course changes of NADPH-d positive neuron counts in the cortex of mice after acute heat stress.Methods:Models of mice after acute heat stress were duplicated. Shuttle box test was used to observe the learning and memory function of mice at 6 h, 12 h, 24 h, respectively after heat stress. NADPH-d histochemical staining test was used to observe the time course changes of NADPH-d positive neuron counts in the cortex of mice at 6 h, 12 h, 24 h respectively after heat stress.Results:Compared with control group, mistakes in heat stress (HS) group was significantly increased while escape latency was significantly shortened at 6 h, 12 h respectively (P<0.05). Compared with control group, NADPH-d positive neuron counts in HS group were significantly increased at 6 h (P<0.05). NADPH-d positive neuron counts in HS group were significantly decreased at 12 h.Conclusions:Acute heat stress could result in obvious damages on learning and memory function of mice, which is possibly related with the increased NADPH-d positive neuron expression.

  19. Changes in time course of NADPH-d positive neuron counts in the cortex of mice after heat stress

    Institute of Scientific and Technical Information of China (English)

    Yan Wang; Ling Chen; Yuzhong Jin

    2016-01-01

    Objective:To discuss the time course changes of NADPH-d positive neuron counts in the cortex of mice after acute heat stress. Methods:Model of mice after acute heat stress were duplicated. Shuttle box test was used to observe the learning and memory function of mice at 6 h, 12 h, 24 h respectively after heat stress. NADPH-d histochemical staining test was used to observe the time course changes of NADPH-d positive neuron counts in the cortex of mice at 6 h, 12 h, 24 h respectively after heat stress. Results:(1) Shuttle box test indicated that:Compared with control group, mistakes (M) in HS (heat stress) group was significantly increased while escape latency (EL) was significantly shortened at 6 h, 12 h respectively. (2) NADPH-d histochemical staining test indicated that:Compared with control group, NADPH-d positive neuron counts in HS group were significantly increased at 6 h, and difference had statistical significance. NADPH-d positive neuron counts in HS group were significantly decreased at 12 h. Conclusion:Acute heat stress could result in obvious damages on learning and memory function of mice, which was possibly related with the increased NADPH-d positive neuron expression.

  20. Cerebral Oedema, Blood-Brain Barrier Breakdown and the Decrease in Na(+),K(+)-ATPase Activity in the Cerebral Cortex and Hippocampus are Prevented by Dexamethasone in an Animal Model of Maple Syrup Urine Disease.

    Science.gov (United States)

    Rosa, Luciana; Galant, Leticia S; Dall'Igna, Dhébora M; Kolling, Janaina; Siebert, Cassiana; Schuck, Patrícia F; Ferreira, Gustavo C; Wyse, Angela T S; Dal-Pizzol, Felipe; Scaini, Giselli; Streck, Emilio L

    2016-08-01

    Maple syrup urine disease (MSUD) is a rare metabolic disorder associated with acute and chronic brain dysfunction. This condition has been shown to lead to macroscopic cerebral alterations that are visible on imaging studies. Cerebral oedema is widely considered to be detrimental for MSUD patients; however, the mechanisms involved are still poorly understood. Therefore, we investigated whether acute administration of branched-chain amino acids (BCAA) causes cerebral oedema, modifies the Na(+),K(+)-ATPase activity, affects the permeability of the blood-brain barrier (BBB) and alters the levels of cytokines in the hippocampus and cerebral cortex of 10-day-old rats. Additionally, we investigated the influence of concomitant administration of dexamethasone on the alterations caused by BCAA. Our results showed that the animals submitted to the model of MSUD exhibited an increase in the brain water content, both in the cerebral cortex and in the hippocampus. By investigating the mechanism of cerebral oedema, we discovered an association between H-BCAA and the Na(+),K(+)-ATPase activity and the permeability of the BBB to small molecules. Moreover, the H-BCAA administration increases Il-1β, IL-6 and TNF-α levels in the hippocampus and cerebral cortex, whereas IL-10 levels were decreased in the hippocampus. Interestingly, we showed that the administration of dexamethasone successfully reduced cerebral oedema, preventing the inhibition of Na(+),K(+)-ATPase activity, BBB breakdown and the increase in the cytokines levels. In conclusion, these findings suggest that dexamethasone can improve the acute cerebral oedema and brain injury associated with high levels of BCAA, either through a direct effect on brain capillary Na(+),K(+)-ATPase or through a generalized effect on the permeability of the BBB to all compounds. PMID:26133302

  1. Neuronal and inducible nitric oxide synthase upregulation in the rat medial prefrontal cortex following acute restraint stress: A dataset

    Directory of Open Access Journals (Sweden)

    Jereme G. Spiers

    2016-03-01

    Full Text Available This data article provides additional evidence on gene expression changes in the neuronal and inducible isoforms of nitric oxide synthase in the medial prefrontal cortex following acute stress. Male Wistar rats aged 6–8 weeks were exposed to control or restraint stress conditions for up to four hours in the dark cycle after which the brain was removed and the medial prefrontal cortex isolated by cryodissection. Following RNA extraction and cDNA synthesis, gene expression data were measured using quantitative real-time PCR. The mRNA levels of the neuronal and inducible nitric oxide synthase isoforms, and the inhibitory subunit of NF-κB, I kappa B alpha were determined using the ΔΔCT method relative to control animals. This data article presents complementary results related to the research article entitled ‘Acute restraint stress induces specific changes in nitric oxide production and inflammatory markers in the rat hippocampus and striatum’ [1].

  2. Effects of Ketamine on Neuronal Spontaneous Excitatory Postsynaptic Currents and Miniature Excitatory Postsynaptic Currents in the Somatosensory Cortex of Rats

    OpenAIRE

    Chengdong Yuan; Yajun Zhang; Yu Zhang; Song Cao; Yuan Wang; Bao Fu; Tian Yu

    2016-01-01

    Background: Ketamine is a commonly used intravenous anesthetic which produces dissociation anesthesia, analgesia, and amnesia. The mechanism of ketamine-induced synaptic inhibition in high-level cortical areas is still unknown. We aimed to elucidate the effects of different concentrations of ketamine on the glutamatergic synaptic transmission of the neurons in the primary somatosensory cortex by using the whole-cell patch-clamp method. Methods: Sprague-Dawley rats (11–19 postnatal days, n=...

  3. Petilla terminology: nomenclature of features of GABAergic interneurons of the cerebral cortex

    OpenAIRE

    Ascoli, Giorgio A.; Yuste, Rafael; The Petilla Interneuron Nomenclature Group (PING); Marín Parra, Oscar

    2008-01-01

    Neuroscience produces a vast amount of data from an enormous diversity of neurons. A neuronal classification system is essential to organize such data and the knowledge that is derived from them. Classification depends on the unequivocal identification of the features that distinguish one type of neuron from another. The problems inherent in this are particularly acute when studying cortical interneurons. To tackle this, we convened a representative group of researchers to agree on a set of t...

  4. Neuronal differentiation of adipose-derived stem cells and their transplantation for cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Guoping Tian; Xiaoguang Luo; Jin Zhou; Jinge Wang; Bing Xu; Li Li; Feng Zhu; Jian Han; Jianping Li; Siyang Zhang

    2012-01-01

    OBJECTIVE: To review published data on the biological characteristics, differentiation and applications of adipose-derived stem cells in ischemic diseases.DATA RETRIEVAL: A computer-based online search of reports published from January 2005 to June 2012 related to the development of adipose-derived stem cells and their transplantation for treatment of cerebral ischemia was performed in Web of Science using the key words"adipose-derived stem cells", "neural-like cells", "transplantation", "stroke", and "cerebral ischemia". SELECTION CRITERIA: The documents associated with the development of adipose-derived stem cells and their transplantation for treatment of cerebral ischemia were selected, and those published in the last 3-5 years or in authoritative journals were preferred in the same field. Totally 89 articles were obtained in the initial retrieval, of which 53 were chosen based on the inclusion criteria. MAIN OUTCOME MEASURES: Biological characteristics and induced differentiation ofadipose-derived stem cells and cell transplantation for disease treatment as well as the underlying mechanism of clinical application. RESULTS: The advantages of adipose-derived stem cells include their ease of procurement, wide availability, rapid expansion, low tumorigenesis, low immunogenicity, and absence of ethical constraints. Preclinical experiments have demonstrated that transplanted adipose-derived stem cells can improve neurological functions, reduce small regions of cerebral infarction, promote angiogenesis, and express neuron-specific markers. The improvement of neurological functions was demonstrated in experiments using different methods and time courses of adipose-derived stem cell transplantation, but the mechanisms remain unclear.CONCLUSION: Further research into the treatment of ischemic disease by adipose-derived stem cell transplantation is needed to determine their mechanism of action.

  5. Synchrony between orientation-selective neurons is modulated during adaptation-induced plasticity in cat visual cortex

    Directory of Open Access Journals (Sweden)

    Shumikhina Svetlana

    2008-07-01

    Full Text Available Abstract Background Visual neurons respond essentially to luminance variations occurring within their receptive fields. In primary visual cortex, each neuron is a filter for stimulus features such as orientation, motion direction and velocity, with the appropriate combination of features eliciting maximal firing rate. Temporal correlation of spike trains was proposed as a potential code for linking the neuronal responses evoked by various features of a same object. In the present study, synchrony strength was measured between cells following an adaptation protocol (prolonged exposure to a non-preferred stimulus which induce plasticity of neurons' orientation preference. Results Multi-unit activity from area 17 of anesthetized adult cats was recorded. Single cells were sorted out and (1 orientation tuning curves were measured before and following 12 min adaptation and 60 min after adaptation (2 pairwise synchrony was measured by an index that was normalized in relation to the cells' firing rate. We first observed that the prolonged presentation of a non-preferred stimulus produces attractive (58% and repulsive (42% shifts of cell's tuning curves. It follows that the adaptation-induced plasticity leads to changes in preferred orientation difference, i.e. increase or decrease in tuning properties between neurons. We report here that, after adaptation, the neuron pairs that shared closer tuning properties display a significant increase of synchronization. Recovery from adaptation was accompanied by a return to the initial synchrony level. Conclusion We conclude that synchrony reflects the similarity in neurons' response properties, and varies accordingly when these properties change.

  6. Layer- and column-specific knockout of NMDA receptors in pyramidal neurons of the mouse barrel cortex.

    Directory of Open Access Journals (Sweden)

    Rachel Aronoff

    2007-11-01

    Full Text Available Viral vectors injected into the mouse brain offer the possibility for localized genetic modifications in a highly controlled manner. Lentivector injection into mouse neocortex transduces cells within a diameter of approximately 200µm, which closely matches the lateral scale of a column in barrel cortex. The depth and volume of the injection determines which cortical layer is transduced. Furthermore, transduced gene expression from the lentivector can be limited to predominantly pyramidal neurons by using a 1.3kb fragment of the αCaMKII promoter. This technique therefore allows genetic manipulation of a specific cell type in defined columns and layers of the neocortex. By expressing Cre recombinase from such a lentivector in gene-targeted mice carrying a floxed gene, highly specific genetic lesions can be induced. Here, we demonstrate the utility of this approach by specifically knocking out NMDA receptors (NMDARs in pyramidal neurons in the somatosensory barrel cortex of gene-targeted mice carrying floxed NMDAR 1 genes. Neurons transduced with lentivector encoding GFP and Cre recombinase exhibit not only reductions in NMDAR 1 mRNA levels, but reduced NMDAR-dependent currents and pairing-induced synaptic potentiation. This technique for knockout of NMDARs in a cell type, column- and layer-specific manner in the mouse somatosensory cortex may help further our understanding of the functional roles of NMDARs in vivo during sensory perception and learning.

  7. Tissue-type plasminogen activator induces synaptic vesicle endocytosis in cerebral cortical neurons.

    Science.gov (United States)

    Yepes, M; Wu, F; Torre, E; Cuellar-Giraldo, D; Jia, D; Cheng, L

    2016-04-01

    The release of the serine proteinase tissue-type plasminogen activator (tPA) from the presynaptic terminal of cerebral cortical neurons plays a central role in the development of synaptic plasticity, adaptation to metabolic stress and neuronal survival. Our earlier studies indicate that by inducing the recruitment of the cytoskeletal protein βII-spectrin and voltage-gated calcium channels to the active zone, tPA promotes Ca(2+)-dependent translocation of synaptic vesicles (SVs) to the synaptic release site where they release their load of neurotransmitters into the synaptic cleft. Here we used a combination of in vivo and in vitro experiments to investigate whether this effect leads to depletion of SVs in the presynaptic terminal. Our data indicate that tPA promotes SV endocytosis via a mechanism that does not require the conversion of plasminogen into plasmin. Instead, we show that tPA induces calcineurin-mediated dynamin I dephosphorylation, which is followed by dynamin I-induced recruitment of the actin-binding protein profilin II to the presynaptic membrane, and profilin II-induced F-actin formation. We report that this tPA-induced sequence of events leads to the association of newly formed SVs with F-actin clusters in the endocytic zone. In summary, the data presented here indicate that following the exocytotic release of neurotransmitters tPA activates the mechanism whereby SVs are retrieved from the presynaptic membrane and endocytosed to replenish the pool of vesicles available for a new cycle of exocytosis. Together, these results indicate that in murine cerebral cortical neurons tPA plays a central role coupling SVs exocytosis and endocytosis. PMID:26820595

  8. Asymmetric activation of the anterior cerebral cortex in recipients of IRECA: Preliminary evidence for the energetic effects of an intention-based biofield treatment modality on human neurophysiology

    NARCIS (Netherlands)

    Pike, C.; Vernon, D.; Hald, L.A.

    2014-01-01

    Neurophysiologic studies of mindfulness link the health benefits of meditation to activation of the left-anterior cerebral cortex. The similarity and functional importance of intention and attentional stance in meditative and biofield therapeutic practices suggest that modulation of recipient anteri

  9. Cl(-) conduction of GABAA receptor complex of synaptic membranes in the cortex of rats at the middle stage of chronic cerebral epileptization (pharmacological kindling).

    Science.gov (United States)

    Rebrov, I G; Karpova, M N; Andreev, A A; Klishina, N Yu; Kalinina, M V; Kusnetzova, L V

    2007-11-01

    Experiments on Wistar rats showed a decrease in basal and muscimol-stimulated 36Cl(-) entry into synaptoneurosomes isolated from the cerebral cortex during the middle stage of kindling (30 mg/kg pentylenetetrazole intraperitoneally for 14 days) characterized by the development of convulsions of higher (2 points) severity in comparison with the previous stage.

  10. AT WHAT AGE IS THE DEVELOPING CEREBRAL-CORTEX OF THE RAT COMPARABLE TO THAT OF THE FULL-TERM NEWBORN HUMAN BABY

    NARCIS (Netherlands)

    ROMIJN, HJ; HOFMAN, MA; GRAMSBERGEN, A

    1991-01-01

    By means of a comparative study of experimental data from the literature we estimated at what age the rat cerebral cortex corresponds to that of the full-term newborn human infant with regard to the degree of maturation. As a result of this study we suggest that the 12-13-day-old rat pup fulfills th

  11. Coupling of cerebral blood flow and oxygen metabolism is conserved for chromatic and luminance stimuli in human visual cortex.

    Science.gov (United States)

    Leontiev, Oleg; Buracas, Giedrius T; Liang, Christine; Ances, Beau M; Perthen, Joanna E; Shmuel, Amir; Buxton, Richard B

    2013-03-01

    The ratio of the changes in cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRO(2)) during brain activation is a critical determinant of the magnitude of the blood oxygenation level dependent (BOLD) response measured with functional magnetic resonance imaging (fMRI). Cytochrome oxidase (CO), a key component of oxidative metabolism in the mitochondria, is non-uniformly distributed in visual area V1 in distinct blob and interblob regions, suggesting significant spatial variation in the capacity for oxygen metabolism. The goal of this study was to test whether CBF/CMRO(2) coupling differed when these subpopulations of neurons were preferentially stimulated, using chromatic and luminance stimuli to preferentially stimulate either the blob or interblob regions. A dual-echo spiral arterial spin labeling (ASL) technique was used to measure CBF and BOLD responses simultaneously in 7 healthy human subjects. When the stimulus contrast levels were adjusted to evoke similar CBF responses (mean 65.4% ± 19.0% and 64.6% ± 19.9%, respectively for chromatic and luminance contrast), the BOLD responses were remarkably similar (1.57% ± 0.39% and 1.59% ± 0.35%) for both types of stimuli. We conclude that CBF-CMRO(2) coupling is conserved for the chromatic and luminance stimuli used, suggesting a consistent coupling for blob and inter-blob neuronal populations despite the difference in CO concentration. PMID:23238435

  12. Corticotrigeminal projections from the insular cortex to the trigeminal caudal subnucleus regulate orofacial pain after nerve injury via extracellular signal-regulated kinase activation in insular cortex neurons

    Directory of Open Access Journals (Sweden)

    Jian eWang

    2015-12-01

    Full Text Available Cortical neuroplasticity alterations are implicated in the pathophysiology of chronic orofacial pain. However, the relationship between critical cortex excitability and orofacial pain maintenance has not been fully elucidated. We recently demonstrated a top-down corticospinal descending pain modulation pathway from the anterior cingulate cortex (ACC to the spinal dorsal horn that could directly regulate nociceptive transmission. Thus, we aimed to investigate possible corticotrigeminal connections that directly influence orofacial nociception in rats. Infraorbital nerve chronic constriction injury (IoN-CCI induced significant orofacial nociceptive behaviors as well as pain-related negative emotions such as anxiety/depression in rats. By combining retrograde and anterograde tract tracing, we found powerful evidence that the trigeminal caudal subnucleus (Vc, especially the superficial laminae (I/II, received direct descending projections from granular and dysgranular parts of the insular cortex (IC. Extracellular signal-regulated kinase (ERK, an important signaling molecule involved in neuroplasticity, was significantly activated in the IC following IoN-CCI. Moreover, in IC slices from IoN-CCI rats, U0126, an inhibitor of ERK activation, decreased both the amplitude and the frequency of spontaneous excitatory postsynaptic currents (sEPSCs and reduced the paired-pulse ratio (PPR of Vc-projecting neurons. Additionally, U0126 also reduced the number of action potentials in the Vc-projecting neurons. Finally, intra-IC infusion of U0126 obviously decreased Fos expression in the Vc, accompanied by the alleviation of both nociceptive behavior and negative emotions. Thus, the corticotrigeminal descending pathway from the IC to the Vc could directly regulate orofacial pain, and ERK deactivation in the IC could effectively alleviate neuropathic pain as well as pain-related negative emotions in IoN-CCI rats, probably through this top-down pathway. These

  13. Remodeling of motor cortex function in acute cerebral infarction patients following human urinary kallidinogenase A functional magnetic resonance imaging evaluation after 6 months

    Institute of Scientific and Technical Information of China (English)

    Xuezhu Song; Lixin Han; Yan Liu

    2012-01-01

    A total of 29 patients were treated within 48 hours after acute subcortical cerebral infarction with Xuesaitong or Xuesaitong plus human urinary kallidinogenase for 14 days. Neurological deficits, activity of daily living, and evaluations of distal upper limb motor functions at the 6-month follow-up showed that patients treated with Xuesaitong plus human urinary kallidinogenase recovered better than with Xuesaitong alone. In addition, functional MRI revealed that activation sites were primarily at the ipsilesional side of injury in all patients. Human urinary kallidinogenase induced hyperactiva-tion of the ipsilesional primary sensorimotor cortex, premotor cortex, supplementary motor area, and contralesional posterior parietal cortex. Results showed that human urinary kallidinogenase improved symptoms of neurological deficiency by enhancing remodeling of long-term cortical motor function in patients with acute cerebral infarction.

  14. Nerve growth factor downregulates c-jun mRNA and Caspase-3 in striate cortex of rats after transient global cerebral ischemia/reperfusion

    Institute of Scientific and Technical Information of China (English)

    Dacheng Jin; Tiemin Wang; Xiubin Fang

    2006-01-01

    solution (PBS, 0.1 mol/L) containing 40 g/L polyformaldehyde, their brains were quickly removed. The coronal section tissue mass containing striate cortex about 3 mm before line between two ears was taken and made into successive frozen sections.④The expression of c-jun Mrna and Caspase-3 protein in striate cortex of global cerebral ischemia rats were detected with in situ hybridization, immunohistochemistry and microscope image analysis. ⑤t test was used for comparing the difference of the measurement data.MATN OUTCOME MEASURES:Comparison of the expression of IEG c-jun Mrna and Caspase-3 protein in striate cortex of brain of rats in each group.RESULTS:All the 18 SD rats were involved in the analysis of results. The c-jun Mrna and Caspase-3 protein positive reaction cells were found brown yellow in the striate cortex of rats, and most of them were in lamellas Ⅱ and Ⅲ, mainly presenting round or oval. The expression of c-jun Mrna and Caspase-3 protein in sham-operation group was weak or negative. The average gray value of c-jun Mrna and Caspase-3 protein in the IR group was significantly lower than that in the sham-operation group (49.52±4.13 vs. 95.48±5.28; 74.73±4.29 vs. 162.38±9.16,P < 0.01). The average gray value of c-jun Mrna and Caspase-3 protein in the NGF group was significantly higher than that in the IR group (63.96±4.25 vs.49.52±4.13; 83.98±4.13 vs. 74.73±4.29, P< 0.05).CONCLUSTON: NGF can protect ischemic neurons by down-regulating the expression of c-jun Mrna and Caspase-3 protein in striate cortex of global cerebral ischemia rats.

  15. Attenuation of γ-aminobutyric acid (GABA) transaminase activity contributes to GABA increase in the cerebral cortex of mice exposed to β-cypermethrin.

    Science.gov (United States)

    Han, Y; Cao, D; Li, X; Zhang, R; Yu, F; Ren, Y; An, L

    2014-03-01

    The current study investigated the γ-aminobutyric acid (GABA) levels and GABA metabolic enzymes (GABA transaminase (GABA(T)) and glutamate decarboxylase (GAD)) activities at 2 and 4 h after treatment, using a high-performance liquid chromatography with ultraviolet detectors and colorimetric assay, in the cerebral cortex of mice treated with 20, 40 or 80 mg/kg β-cypermethrin by a single oral gavage, with corn oil as vehicle control. In addition, GABA protein (4 h after treatment), GABA(T) protein (2 h after treatment) and GABA receptors messenger RNA (mRNA) expression were detected by immunohistochemistry, Western blot and real-time quantitative reverse transcriptase polymerase chain reaction, respectively. β-Cypermethrin (80 mg/kg) significantly increased GABA levels in the cerebral cortex of mice, at both 2 and 4 h after treatment, compared with the control. Also, GABA immunohistochemistry results suggested that the number of positive granules was increased in the cerebral cortex of mice 4 h after exposure to 80 mg/kg β-cypermethrin when compared with the control. Furthermore, the results also showed that GABA(T) activity detected was significantly decreased in the cerebral cortex of mice 2 h after β-cypermethrin administration (40 or 80 mg/kg). No significant changes were found in GAD activity, or the expression of GABA(T) protein and GABAB receptors mRNA, in the cerebral cortex of mice, except that 80 mg/kg β-cypermethrin caused a significant decrease, compared with the vehicle control, in GABAA receptors mRNA expression 4 h after administration. These results suggested that attenuated GABA(T) activity induced by β-cypermethrin contributed to increased GABA levels in the mouse brain. The downregulated GABAA receptors mRNA expression is most likely a downstream event.

  16. Chimera in a neuronal network model of the cat brain

    OpenAIRE

    Santos, M. S.; Szezech Jr., J. D.; Borges, F. S.; Iarosz, K. C.; Caldas, I. L.; Batista, A. M.; Viana, R. L.; Kurths, J.

    2016-01-01

    Neuronal systems have been modeled by complex networks in different description levels. Recently, it has been verified that networks can simultaneously exhibit one coherent and other incoherent domain, known as chimera states. In this work, we study the existence of chimera states in a network considering the connectivity matrix based on the cat cerebral cortex. The cerebral cortex of the cat can be separated in 65 cortical areas organised into the four cognitive regions: visual, auditory, so...

  17. Mild systemic inflammation and moderate hypoxia transiently alter neuronal excitability in mouse somatosensory cortex.

    Science.gov (United States)

    Mordel, Jérôme; Sheikh, Aminah; Tsohataridis, Simeon; Kanold, Patrick O; Zehendner, Christoph M; Luhmann, Heiko J

    2016-04-01

    During the perinatal period, the brain is highly vulnerable to hypoxia and inflammation, which often cause white matter injury and long-term neuronal dysfunction such as motor and cognitive deficits or epileptic seizures. We studied the effects of moderate hypoxia (HYPO), mild systemic inflammation (INFL), or the combination of both (HYPO+INFL) in mouse somatosensory cortex induced during the first postnatal week on network activity and compared it to activity in SHAM control animals. By performing in vitro electrophysiological recordings with multi-electrode arrays from slices prepared directly after injury (P8-10), one week after injury (P13-16), or in young adults (P28-30), we investigated how the neocortical network developed following these insults. No significant difference was observed between the four groups in an extracellular solution close to physiological conditions. In extracellular 8mM potassium solution, slices from the HYPO, INFL, and HYPO+INFL group were more excitable than SHAM at P8-10 and P13-16. In these two age groups, the number and frequency of spontaneous epileptiform events were significantly increased compared to SHAM. The frequency of epileptiform events was significantly reduced by the NMDA antagonist D-APV in HYPO, INFL, and HYPO+INFL, but not in SHAM, indicating a contribution of NMDA receptors to this pathophysiological activity. In addition, the AMPA/kainate receptor antagonist CNQX suppressed the remaining epileptiform activity. Electrical stimulation evoked prominent epileptiform activity in slices from HYPO, INFL and HYPO+INFL animals. Stimulation threshold to elicit epileptiform events was lower in these groups than in SHAM. Evoked events spread over larger areas and lasted longer in treated animals than in SHAM. In addition, the evoked epileptiform activity was reduced in the older (P28-30) group indicating that cortical dysfunction induced by hypoxia and inflammation was transient and compensated during early development.

  18. [Effects of ketamine and urethane on stimulation-induced c-fos expression in neurons of cat visual cortex].

    Science.gov (United States)

    Wang, Ke; Zhu, Hui; Chen, Cui-Yun; Li, Peng; Jin, Cai-Hong; Wang, Zi-Lu; Jiang, San; Hua, Tian-Miao

    2013-12-01

    The effects of ketamine and urethane on neuronal activities remain in debate. As a member of immediate early genes family, the expression of c-fos is stimulation dependent and could be treated as an index to evaluate the strength of neural activities. In this study, SABC immunohistochemical techniques were applied to compare the c-fos expression in neurons of the primary visual cortex (V1) of cats and therefore, to evaluate the effects of acute anesthesia with ketamine HCl and uethane on inhibiting neural activities. Our results showed that compared with control cats, there were no significant differences with the average densities of Nissl-stained V1 neurons in each cortical layers of either urethane or ketamine anesthetized cats. In urethane anesthetized cats, neither the average densities nor the immunoreactive intensities of c-fos positive V1 neurons showed significant difference with that of control ones. However, both the average densities and immunoreactive intensities of c-fos positive V1 neurons in ketamine anesthetized cats decreased significantly compared with that of control and urethane anesthetized cats. These results suggested that ketamine has strong inhibitory effects on the activities of visual cortical neurons, whereas urethane did not. PMID:24415690

  19. The facilitatory influence of anterior cingulate cortex on ON-OFF response of tactile neuron in thalamic ventrobasal nucleus

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The structures of limbic system have been found to modulate the auditory, visual and pain afferent signals in the related nuclei of thalamus. One of those structures is anterior cingulate cortex (ACC) that influences nocuous response of the pain-sensitive neurons in the ventropostero-lateral nucleus of thalamus. Thus, we inferred that ACC would also modulate tactile information at the thalamic level. To test this assumption, single units were recorded extracellularly from thalamic ventrobasal nucleus (VB). Tactile ON-OFF response and the relationship between different patterns of the responses and the parameters of tactile stimulation were examined. Furthermore, the influence of ACC on the tactile ON-OFF response was studied. ACC stimulation was found to produce a facilitatory effect on the OFF-response of ON-OFF neurons. It lowered the threshold of the off-response of that neuron, and therefore changed the response pattern or enhanced the firing rate of the OFF-response of the neuron. The study on receptive fields of ON-OFF neurons showed that the excitation of the ACC could change an ON-response on the verge of a receptive field into an ON-OFF response. The above results suggest that the ACC modulation sharpens the response of a VB neuron to a moving stimulus within its receptive field, indicating that the limbic system can modulate tactile ascending sensory information.

  20. Desynchronization and rebound of beta oscillations during conscious and unconscious local neuronal processing in the macaque lateral prefrontal cortex.

    Science.gov (United States)

    Panagiotaropoulos, Theofanis I; Kapoor, Vishal; Logothetis, Nikos K

    2013-01-01

    Accumulating evidence indicates that control mechanisms are not tightly bound to conscious perception since both conscious and unconscious information can trigger control processes, probably through the activation of higher-order association areas like the prefrontal cortex. Studying the modulation of control-related prefrontal signals in a microscopic, neuronal level during conscious and unconscious neuronal processing, and under control-free conditions could provide an elementary understanding of these interactions. Here we performed extracellular electrophysiological recordings in the macaque lateral prefrontal cortex (LPFC) during monocular physical alternation (PA) and binocular flash suppression (BFS) and studied the local scale relationship between beta (15-30 Hz) oscillations, a rhythmic signal believed to reflect the current sensory, motor, or cognitive state (status-quo), and conscious or unconscious neuronal processing. First, we show that beta oscillations are observed in the LPFC during resting state. Both PA and BFS had a strong impact on the power of this spontaneous rhythm with the modulation pattern of beta power being identical across these two conditions. Specifically, both perceptual dominance and suppression of local neuronal populations in BFS were accompanied by a transient beta desynchronization followed by beta activity rebound, a pattern also observed when perception occurred without any underlying visual competition in PA. These results indicate that under control-free conditions, at least one rhythmic signal known to reflect control processes in the LPFC (i.e., beta oscillations) is not obstructed by local neuronal, and accordingly perceptual, suppression, thus being independent from temporally co-existing conscious and unconscious local neuronal representations. Future studies could reveal the additive effects of motor or cognitive control demands on prefrontal beta oscillations during conscious and unconscious processing.

  1. Controle neuronal e manifestações digestórias na paralisia cerebral

    Directory of Open Access Journals (Sweden)

    Liubiana A. Araújo

    2012-12-01

    Full Text Available OBJETIVOS: Abordar as peculiaridades do controle neuronal digestório e descrever as principais manifestações digestórias na paralisia cerebral, atentando-se à importância do diagnóstico precoce para intervenção interdisciplinar eficaz. FONTES DOS DADOS: Revisão sistemática de 1997 a 2012 das bases de dados MEDLINE, LILACS, SciELO e Cochrane Library. Incluem-se 70 artigos, como revisões relevantes, estudos observacionais, ensaios clínicos e estudos de prevalência. Excluíram-se pesquisas qualitativas. Os termos pesquisados foram: paralisia cerebral, disfagia, doença do refluxo gastroesofágico, constipação intestinal, infecção respiratória e gastrostomia. SÍNTESE DOS DADOS: O controle adequado do trato digestório depende do funcionamento e integridade do sistema nervoso. Como indivíduos portadores de paralisia cerebral possuem anormalidades estruturais evidentes no sistema nervoso central e periférico, estão mais propensos a desenvolver distúrbios do trato digestório, com repercussões nutricionais. As alterações vão desde imaturidade neurológica até interferência do estado de humor e capacitação dos cuidadores. Trata-se, portanto, de etiologia multifatorial. As desordens digestórias mais prevalentes são disfagia, doença do refluxo gastroesofágico e constipação intestinal, com consequentes quadros de infecções respiratórias de repetição e repercussão deletéria no estado nutricional. CONCLUSÕES: Indivíduos com paralisia cerebral apresentam alterações neurológicas do controle do sistema digestório, portanto manifestações digestórias são frequentes. As questões abordadas são fundamentais para profissionais das equipes interdisciplinares que atendem indivíduos com paralisia cerebral acerca da importância da anamnese ampla, exame clínico e complementar detalhado que incluam investigação das desordens gastrointestinais associadas e suas consequências. A detecção precoce dessas altera

  2. Immunochemical characterization of inhibitory mouse cortical neurons: Three chemically distinct classes of inhibitory cells

    OpenAIRE

    Xu, Xiangmin; Roby, Keith D.; Edward M Callaway

    2010-01-01

    The cerebral cortex has diverse types of inhibitory neurons. In rat cortex, past research has shown that parvalbumin (PV), somatostatin (SOM), calretinin (CR), and cholecystokinin (CCK) label four distinct chemical classes of GABAergic interneurons. However, in contrast to rat cortex, previous studies indicate that there is significant co-localization of SOM and CR in mouse cortical inhibitory neurons. In the present study, we further characterized immunochemical distinctions among mouse inhi...

  3. Growth of the Developing Cerebral Cortex Is Controlled by MicroRNA-7 through the p53 Pathway

    Directory of Open Access Journals (Sweden)

    Andrew Pollock

    2014-05-01

    Full Text Available Proper growth of the mammalian cerebral cortex is crucial for normal brain functions and is controlled by precise gene-expression regulation. Here, we show that microRNA-7 (miR-7 is highly expressed in cortical neural progenitors and describe miR-7 sponge transgenic mice in which miR-7-silencing activity is specifically knocked down in the embryonic cortex. Blocking miR-7 function causes microcephaly-like brain defects due to reduced intermediate progenitor (IP production and apoptosis. Upregulation of miR-7 target genes, including those implicated in the p53 pathway, such as Ak1 and Cdkn1a (p21, is responsible for abnormalities in neural progenitors. Furthermore, ectopic expression of Ak1 or p21 and specific blockade of miR-7 binding sites in target genes using protectors in vivo induce similarly reduced IP production. Using conditional miRNA sponge transgenic approaches, we uncovered an unexpected role for miR-7 in cortical growth through its interactions with genes in the p53 pathway.

  4. An enhanced role and expanded developmental origins for gamma-aminobutyric acidergic interneurons in the human cerebral cortex.

    Science.gov (United States)

    Clowry, Gavin J

    2015-10-01

    Human beings have considerably expanded cognitive abilities compared with all other species and they also have a relatively larger cerebral cortex compared with their body size. But is a bigger brain the only reason for higher cognition or have other features evolved in parallel? Humans have more and different types of GABAergic interneurons, found in different places, than our model species. Studies are beginning to show differences in function. Is this expanded repertoire of functional types matched by an evolution of their developmental origins? Recent studies support the idea that generation of interneurons in the ventral telencephalon may be more complicated in primates, which have evolved a large and complex outer subventricular zone in the ganglionic eminences. In addition, proportionally more interneurons appear to be produced in the caudal ganglionic eminence, the majority of which populate the superficial layers of the cortex. Whether or not the cortical proliferative zones are a source of interneurogenesis, and to what extent and of what significance, is a contentious issue. As there is growing evidence that conditions such as autism, schizophrenia and congenital epilepsy may have developmental origins in the failure of interneuron production and migration, it is important we understand fully the similarities and differences between human development and our animal models.

  5. Acetylcholine modulates transient outward potassium channel in acutely isolated cerebral cortical neurons of rats

    Institute of Scientific and Technical Information of China (English)

    Lanwei Cui; Tao Sun; Lihui Qu; Yurong Li; Haixia Wen

    2009-01-01

    BACKGROUND:The neuronal transient outward potassium channel has been shown to be highly associated with acetylcholine.However,the influence of acetylcholine on the transient outward potassium current in cerebral cortical neurons remains poorly understood.OBJECTIVE:To investigate acetylcholine modulation on transient outward potassium current in rat parietal cortical neurons using the whole-cell patch-clamp technique.DESIGN,TIME AND SETTING:A neuroelectrophysiology study was performed at the Department of Physiology,Harbin Medical University between January 2005 and January 2006.MATERIALS:Wistar rats were provided by the Animal Research Center,the Second Hospital of Harbin Medical University;PC-IIC patch-clamp amplifier and IBBClamp data collection analysis system were provided by Huazhong University for Science and Technology,Wuhan,China;PP-83 microelectrode puller was purchased from Narrishage,Japan.METHODS:The parietal somatosensory cortical neurons were acutely dissociated,and the modulation of acetylcholine (0.1,1,10,100 μmol/L) on transient outward potassium channel was recorded using the whole-cell patch-clamp technique.MAIN OUTCOME MEASURES:Influence of acetylcholine on transient outward potassium current,potassium channel activation,and inactivation.RESULTS:The inhibitory effect of acetylcholine on transient outward potassium current was dose- and voltage-dependent (P<0.01).Acetylcholine was found to significantly affect the activation process of transient outward potassium current,i.e.,the activation curve of transient outward potassium current was left-shifted,while the inactivation curve was shifted to hyperpolarization.Acetylcholine significantly prolonged the time constant of recovery from inactivation of transient outward potassium current (P<0.01).CONCLUSION:These results suggest that acetylcholine inhibits transient outward potassium current by regulating activation and inactivation processes of the transient outward potassium channel.

  6. Inhibition of propofol on single neuron and neuronal ensemble activity in prefrontal cortex of rats during working memory task.

    Science.gov (United States)

    Xu, Xinyu; Tian, Yu; Wang, Guolin; Tian, Xin

    2014-08-15

    Working memory (WM) refers to the temporary storage and manipulation of information necessary for performance of complex cognitive tasks. There is a growing interest in whether and how propofol anesthesia inhibits WM function. The aim of this study is to investigate the possible inhibition mechanism of propofol anesthesia from the view of single neuron and neuronal ensemble activities. Adult SD rats were randomly divided into two groups: propofol group (0.9 mg kg(-1)min(-1), 2h via a tail vein catheter) and control group. All the rats were tested for working memory performances in a Y-maze-rewarded alternation task (a task of delayed non-matched-to-sample) at 24, 48, 72 h after propofol anesthesia, and the behavior results of WM tasks were recorded at the same time. Spatio-temporal trains of action potentials were obtained from the original signals. Single neuron activity was characterized by peri-event time histograms analysis and neuron ensemble activities were characterized by Granger causality to describe the interactions within the neuron ensemble. The results show that: comparing with the control group, the percentage of neurons excited and related to WM was significantly decreased (pneuron ensemble were significantly weakened (p0.05), which were consistent with the behavior results. These findings could lead to improved understanding of the mechanism of anesthesia inhibition on WM functions from the view of single neuron activity and neuron ensemble interactions.

  7. Inosine inhibits apoptosis and cytochrome C mRNA expression in rat neurons after cerebral ischemia/reperfusion

    Institute of Scientific and Technical Information of China (English)

    Jinrong Wang; Mingjun Bi; Qin Li

    2006-01-01

    BACKGROUND: It has been demonstrated that adenosine can induce glial cell to release cytochrome C,enhance expression of apoptotic gene bax,inhibit anti-apoptotic gene bcl-2,and activate caspase-3 to apoptosis;Whereas inosine can inhibit neuronal apoptosis which is similar to bil-2.OBJECTIVE: To observe the affects of inosine on neuronal apoptosis and expression of cytochrome C mRNA in rats after focal cerebral ischemia/reperfusion,and analyze the pathway of its neuroprotective effect.DESIGN: A randomised controlled animal trial.SETTINGS: Department of Neurology,Rongcheng Second People's Hospital;Department of Neruology,Affiliated Union Hospital,Tongji Medical College,Huazhong University of Science and Technology.MATERIALS: Sixty-eight rats,weighing 230-280 g and clean grade,were used.TdT-mediated dUTP-biotin nick end labeling(TUNEL)and cytochrome C mRNA in situ hybridization kits and DAB staining kit were purchased from Wuhan Boster Biological Co.,Ltd;Inosine injection[200mg(2ml)each] from Qingdao First Pharmaceutical Factory.METHODS:The experiment was accomplished in the animal experimental center in Tongji Medical College of Huazhong University of Science and Technology from December 2003 to June 2005.①Sixty-four rats were made into focal ischemia by middle cerebral artery occlusion(MCAO)with a nylon monofilament suture.The successfully induced rats were assigned to inosine group(n=32)and model group(n=32)at random.Rats in the inosine group were intraperitoneally administrated with inosine in dose of 100mg/kg preoperatively.twice a day,7 days in all.The rats in the control group were injected with the same dose of saline solution by the similar way preoperatively.Each group was randomized into ischemia/reperfusion 2,6,12,24 hours,2,3,7 and 14 days subgroups consisted of 4 rats.The other 4 rats were taken as the sham-operated group,the rats were given the same treatment except for not introduced the filament into the external carotid artery stump.and brain

  8. EFFECT OF ELECTROACUPUNCTURE OF SCALP-POINTS ON ABNORMAL DISCHARGES OF NEURONS AROUND THE CEREBRAL HEMORRHAGE FOCUS IN THE RAT

    Institute of Scientific and Technical Information of China (English)

    东红升; 东贵荣; 白妍

    2004-01-01

    Objective: To study the mechanism of electroacupuncture (EA) of scalp-points for regulating abnormal discharges of neurons in different regions around the cerebral hemorrhage focus by using neuro-electrophysiological methods. Methods: 80 Wistar rats (anesthetized with 20% urethane 1 g/kg, I.p.) were randomly divided into normal, saline, model and EA groups, with 20 cases in each group. Cerebral hemorrhage model was established by intracerebral injection of the rat's own arterial blood sample (40 uL). In rats of saline group, the same volume of saline was given for intracerebral injection. Extracellular electrical activity of neurons of the caudate nucleus and parafascicular nucleus and Tail filiform needles and stimulated electrically with stimulating parameters of strength of 1 V, frequency of 15 Hz and duration of 15 min. Results: Compared with normal group, TFL values of model group and EA group increased significantly (P<0.01); and compared with model group, those of EA group decreased significantly (P<0.01), suggesting that the pain threshold increased significantly in cerebral hemorrhage rats while after acupuncture stimulation, it lowered strikingly. Compared with normal and saline groups, the latency values of the pain excitement and inhibitory responses of the cellular discharges of the caudate and parafascicular nuclei in model and EA groups increased significantly (P<0.05~0.01), while after EA, it recovered apparently (P<0.01), showing an apparent regulative effect of EA on the abnormal changes of discharges of neurons around the cerebral hemorrhage focus. Conclusion: Scalp-acupuncture possesses an apparent regulatory effect on the abnormal electrical activity of neurons around the cerebral hemorrhage focus which may favor the early recovery of functional activity of neurons near the focus tissues.

  9. Effect of Cistanche Desertica Polysaccharides on Learning and Memory Functions and Ultrastructure of Cerebral Neurons in Experimental Aging Mice

    Institute of Scientific and Technical Information of China (English)

    孙云; 邓杨梅; 王德俊; 沈春锋; 刘晓梅; 张洪泉

    2001-01-01

    To observe the effects of Cistanche desertica polysaccharides (CDP) on the learning and memory functions and cerebral ultrastructure in experimental aging mice. Methods: CDP was administrated intragastrically 50 or 100 mg/kg per day for 64 successive days to experimental aging model mice induced by D-galactose, then the learning and memory functions of mice were estimated by step-down test and Y-maze test; organelles of brain tissue and cerebral ultrastructure were observed by transmission electron microscope and physical strength was determined by swimming test. Results: CDP could obviously enhance the learning and memory functions (P<0.01) and prolong the swimming time (P<0.05), decrease the number of lipofuscin and slow down the degeneration of mitochondria in neurons(P<0.05), and improve the degeneration of cerebral ultra-structure in aging mice. Conclusion: CDP could improve the impaired physiological function and alleviate cerebral morphological change in experimental aging mice.

  10. Two-dimensional electrophoretogram of acute brain injury-associated proteins Comparison between Injured and normal cerebral cortex

    Institute of Scientific and Technical Information of China (English)

    Xuejun Li; Xianrui Yuan; Cui Li; Zefeng Peng; Dun Yuan

    2008-01-01

    cerebral cortex; ②differential protein expression. RESULTS:①Two-dimensional electrophoresis of protein from cerebral cortex:two-dimensional gel electrophoretogram,which is considered to have high resolution and consistent duplication,was performed on injured cortical tissues and normal cortical tissues.The image analysis system detected 21 differential protein pots.②Differential protein spot expressions:mass spectrometry resulted in 17 differential protein spots that related to metabolic response,oxidative stress response,and signal transduction.CONCLUSION:MALDI/TOF MS and ESI-Qq TOF MS are exceptional methods for evaluating differential protein expression.Results from this study indicated 17 different craniocerebral injury-associated proteins.

  11. Early asymmetry of gene transcription between embryonic human left and right cerebral cortex

    OpenAIRE

    Sun, Tao; Patoine, Christina; Abu-Khalil, Amir; Visvader, Jane; Sum, Eleanor; Cherry, Timothy J.; Orkin, Stuart H.; Geschwind, Daniel H.; Walsh, Christopher A.

    2005-01-01

    The human left and right cerebral hemispheres are anatomically and functionally asymmetric. To test whether human cortical asymmetry has a molecular basis, we studied gene expression levels between the left and right embryonic hemispheres using Serial Analysis of Gene Expression (SAGE), and identified and verified 27 differentially expressed genes, suggesting that human cortical asymmetry is accompanied by early, striking transcriptional asymmetries. LMO4 is consistently more highly expressed...

  12. Neocortical Maturation during Adolescence: Change in Neuronal Soma Dimension

    Science.gov (United States)

    Rabinowicz, Theodore; Petetot, Jean MacDonald-Comber; Khoury, Jane C.; de Courten-Myers, Gabrielle M.

    2009-01-01

    During adolescence, cognitive abilities increase robustly. To search for possible related structural alterations of the cerebral cortex, we measured neuronal soma dimension (NSD = width times height), cortical thickness and neuronal densities in different types of neocortex in post-mortem brains of five 12-16 and five 17-24 year-olds (each 2F,…

  13. Superficially projecting principal neurons in layer V of medial entorhinal cortex in the rat receive excitatory retrosplenial input.

    Science.gov (United States)

    Czajkowski, Rafał; Sugar, Jørgen; Zhang, Sheng-Jia; Couey, Jonathan J; Ye, Jing; Witter, Menno P

    2013-10-01

    Principal cells in layer V of the medial entorhinal cortex (MEC) have a nodal position in the cortical-hippocampal network. They are the main recipients of hippocampal output and receive inputs from several cortical areas, including a prominent one from the retrosplenial cortex (RSC), likely targeting basal dendrites of layer V neurons. The latter project to extrahippocampal structures but also relay information to the superficial layers of MEC, closing the hippocampal-entorhinal loop. In the rat, we electrophysiologically and morphologically characterized RSC input into MEC and conclude that RSC provides an excitatory input to layer V pyramidal cells. Ultrastructural analyses of anterogradely labeled RSC projections showed that RSC axons in layer V of MEC form predominantly asymmetrical, likely excitatory, synapses on dendritic spines (90%) or shafts (8%), with 2% symmetrical, likely inhibitory, synapses on shafts and spines. The overall excitatory nature of the RSC input was confirmed by an optogenetic approach. Patterned laser stimulation of channelrhodopsin-expressing presynaptic RSC axons evoked exclusively EPSPs in recorded postsynaptic layer V cells. All responding layer V pyramidal cells had an axon extending toward the white matter. Half of these neurons also sent an axon to superficial layers. Confocal imaging of RSC synapses onto MEC layer V neurons shown to project superficially by way of retrogradely labeling from superficial layers confirmed that proximal dendrites of superficially projecting cells are among the targets of inputs from RSC. The excitatory RSC input thus interacts with both entorhinal-cortical and entorhinal-hippocampal circuits.

  14. Top-down inputs enhance orientation selectivity in neurons of the primary visual cortex during perceptual learning.

    Directory of Open Access Journals (Sweden)

    Samat Moldakarimov

    2014-08-01

    Full Text Available Perceptual learning has been used to probe the mechanisms of cortical plasticity in the adult brain. Feedback projections are ubiquitous in the cortex, but little is known about their role in cortical plasticity. Here we explore the hypothesis that learning visual orientation discrimination involves learning-dependent plasticity of top-down feedback inputs from higher cortical areas, serving a different function from plasticity due to changes in recurrent connections within a cortical area. In a Hodgkin-Huxley-based spiking neural network model of visual cortex, we show that modulation of feedback inputs to V1 from higher cortical areas results in shunting inhibition in V1 neurons, which changes the response properties of V1 neurons. The orientation selectivity of V1 neurons is enhanced without changing orientation preference, preserving the topographic organizations in V1. These results provide new insights to the mechanisms of plasticity in the adult brain, reconciling apparently inconsistent experiments and providing a new hypothesis for a functional role of the feedback connections.

  15. Wiener-Volterra characterization of neurons in primary auditory cortex using poisson-distributed impulse train inputs.

    Science.gov (United States)

    Pienkowski, Martin; Shaw, Greg; Eggermont, Jos J

    2009-06-01

    An extension of the Wiener-Volterra theory to a Poisson-distributed impulse train input was used to characterize the temporal response properties of neurons in primary auditory cortex (AI) of the ketamine-anesthetized cat. Both first- and second-order "Poisson-Wiener" (PW) models were tested on their predictions of temporal modulation transfer functions (tMTFs), which were derived from extracellular spike responses to periodic click trains with click repetition rates of 2-64 Hz. Second-order (i.e., nonlinear) PW fits to the measured tMTFs could be described as very good in a majority of cases (e.g., predictability >or=80%) and were almost always superior to first-order (i.e., linear) fits. In all sampled neurons, second-order PW kernels showed strong compressive nonlinearities (i.e., a depression of the impulse response) but never expansive nonlinearities (i.e., a facilitation of the impulse response). In neurons with low-pass tMTFs, the depression decayed exponentially with the interstimulus lag, whereas in neurons with band-pass tMTFs, the depression was typically double-peaked, and the second peak occurred at a lag that correlated with the neuron's best modulation frequency. It appears that modulation-tuning in AI arises in part from an interplay of two nonlinear processes with distinct time courses. PMID:19321635

  16. No Reduction of Spindle Neuron Number in Frontoinsular Cortex in Autism

    Science.gov (United States)

    Kennedy, Daniel P.; Semendeferi, Katerina; Courchesne, Eric

    2007-01-01

    It has been suggested that spindle neurons, an evolutionarily unique type of neuron, might be involved in higher-order social, emotional, and cognitive functions. As such, it was hypothesized that these neurons may be particularly important to the pathophysiology of autism, a disease characterized in part by disruption of higher-order social and…

  17. Loss of endoplasmic reticulum Ca homeostasis:contribution to neuronal cell death during cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Ankur BODALIA; Hongbin LI; Michael F JACKSON

    2013-01-01

    The loss of Ca2+ homeostasis during cerebral ischemia is a hallmark of impending neuronal demise.Accordingly,considerable cellular resources are expended in maintaining low resting cytosolic levels of Ca2+.These include contributions by a host of proteins involved in the sequestration and transport of Ca2+,many of which are expressed within intracellular organelles,including lysosomes,mitochondria as well as the endoplasmic reticulum (ER).Ca2+ sequestration by the ER contributes to cytosolic Ca2+ dynamics and homeostasis.Furthermore,within the ER Ca2+ plays a central role in regulating a host of physiological processes.Conversely,impaired ER Ca2+ homeostasis is an important trigger of pathological processes.Here we review a growing body of evidence suggesting that ER dysfunction is an important factor contributing to neuronal injury and loss post-ischemia.Specifically,the contribution of the ER to cytosolic Ca2+ elevations during ischemia will be considered,as will the signalling cascades recruited as a consequence of disrupting ER homeostasis and function.

  18. Subpallial origin of a population of projecting pioneer neurons during corticogenesis

    OpenAIRE

    Morante-Oria, Javier; Carleton, Alan; Ortino, Barbara; Kremer, Eric J.; Fairén, Alfonso; Lledo, Pierre-Marie

    2003-01-01

    Pyramidal neurons of the mammalian cerebral cortex are generated in the ventricular zone of the pallium whereas the subpallium provides the cortex with inhibitory interneurons. The marginal zone contains a subpial stream of migratory interneurons and two different classes of transient neurons, the pioneer neurons provided with corticofugal axons, and the reelin-expressing Cajal–Retzius cells. We found in cultured slices that the medial ganglionic eminence provides the reelin-negative pioneer ...

  19. Neuronal quantity and ultrastructure in extracorticospinal tract of newborn rabbits with cerebral palsy

    Institute of Scientific and Technical Information of China (English)

    Xiaojie Li; Ying Yang; Zhimei Jiang; Lanrnin Guo; Jing Gao

    2006-01-01

    BACKGROUND: The liver enzyme system and blood brain barrier function of newborn rabbits are incomplete.High level of bilirubin can lead to cerebral palsy (CP) of newborn rabbits. The pathological and ultrastructural changes of brains of immature rabbits may differ from those of mature rabbits.OBJECTIVE: To observe the changes in dopaminergic neuron amount and ultrastructure in the extracorticospinal tract of animal models of CP induced by hyperbilirubinemia.DESIGN: A randomized controlled observation.SETTING: Rehabilitation Medical College of Jiamusi University; Laboratory for Pediatric Neurology Rehabilitation of Jiamusi University.MATERIALS: Thirty newborn 2- to 5- day inbred Japanese rabbits, weighing about 50 g, of either gender, were provided by Experimental Animal Center, Jilin University. Bilirubin and tyrosine hydroxylase (TH) antibody were purchased from Sigma Corporation, USA.METHODS: This experiment was carried out in the laboratory for children neuro-rehabilitation, Jiamusi University between September 2002 and December 2005. ①Thirty rabbits were randomly divided into 2groups: control group (n =10) and model group (n =20). ②Bilirubin of 100 mg/kg was given to the rabbits of model group through intraperitoneal injection, once every other day, 3 times totally; The same amount of normal saline was given to the rabbits of control group. After injection, the newborn rabbits had been fed by maternal milk for 45 days. ③TH-positive neurons in substantia nigra and corpora striatum in each area of0.15 mm ×0.15 mm were counted. Uitrastructures of substantia nigra and corpora striatum were observed under the electron miscroscope. The concentration of bilirubin in brain tissue of CP rabbits of model group was measured with high performance liquid chromatogram.MAIN OUTCOME MEASURES: Quantitative analysis results and ultrastructure of TH-positive neurons in substantia nigra and corpora striatum in two groups.RESULTS: Thirty newborn rabbits were involved, 6

  20. Nitric oxide synthase and neuronal NADPH diaphorase are identical in brain and peripheral tissues.

    OpenAIRE

    Dawson, T. M.; Bredt, D S; M Fotuhi; Hwang, P M; Snyder, S. H.

    1991-01-01

    NADPH diaphorase staining neurons, uniquely resistant to toxic insults and neurodegenerative disorders, have been colocalized with neurons in the brain and peripheral tissue containing nitric oxide synthase (EC 1.14.23.-), which generates nitric oxide (NO), a recently identified neuronal messenger molecule. In the corpus striatum and cerebral cortex, NO synthase immunoreactivity and NADPH diaphorase staining are colocalized in medium to large aspiny neurons. These same neurons colocalize with...

  1. Functional Near-Infrared Spectroscopy Signals Measure Neuronal Activity in the Cortex

    Science.gov (United States)

    Harrivel, Angela; Hearn, Tristan

    2013-01-01

    Functional near infrared spectroscopy (fNIRS) is an emerging optical neuroimaging technology that indirectly measures neuronal activity in the cortex via neurovascular coupling. It quantifies hemoglobin concentration ([Hb]) and thus measures the same hemodynamic response as functional magnetic resonance imaging (fMRI), but is portable, non-confining, relatively inexpensive, and is appropriate for long-duration monitoring and use at the bedside. Like fMRI, it is noninvasive and safe for repeated measurements. Patterns of [Hb] changes are used to classify cognitive state. Thus, fNIRS technology offers much potential for application in operational contexts. For instance, the use of fNIRS to detect the mental state of commercial aircraft operators in near real time could allow intelligent flight decks of the future to optimally support human performance in the interest of safety by responding to hazardous mental states of the operator. However, many opportunities remain for improving robustness and reliability. It is desirable to reduce the impact of motion and poor optical coupling of probes to the skin. Such artifacts degrade signal quality and thus cognitive state classification accuracy. Field application calls for further development of algorithms and filters for the automation of bad channel detection and dynamic artifact removal. This work introduces a novel adaptive filter method for automated real-time fNIRS signal quality detection and improvement. The output signal (after filtering) will have had contributions from motion and poor coupling reduced or removed, thus leaving a signal more indicative of changes due to hemodynamic brain activations of interest. Cognitive state classifications based on these signals reflect brain activity more reliably. The filter has been tested successfully with both synthetic and real human subject data, and requires no auxiliary measurement. This method could be implemented as a real-time filtering option or bad channel

  2. The expression of cholecystokinin and prolactin in cerebral cortex of developing rats with seizure induced by acute heat stress%发育期热水浴诱发惊厥大鼠大脑皮层催乳素和胆囊收缩素蛋白表达的研究

    Institute of Scientific and Technical Information of China (English)

    陈大庆; 倪宏; 水泉祥; 丁振尧; 李上淼

    2009-01-01

    Objective To analyze the distribution of cholecystokinin (CCK) and prolactin (PRL) positive cells in rat' s brain following heat stress (HS) and febrile convulsion ( FC). Methods Acute heat stress model of seizure induced by warm water was developed in this study. Adjacent section immunohistochemical staining method was used to observe expression of CCK and PRL in cerebral cortex. Results (1) There were similar distributions of CCK and PRL positive cells in cerebral cortex of HS group. (2) Both HS and FC rats showed more positive neurons in cerebral cortex than those in control group (P < 0. 01). There were significant more CCK positive neurons in cerebral cortex than that in HS group(P <0. 01) .however,no significant difference of PRL positive neurons was found in piriform cortex and entorhinal cortex between HS and FC group(P>0.05) ,but the difference was significant in perirhinal cortex and parietal cortex. (3)Correlation and regression analysis of the data of CCK and PRL positive units demonstrated that the immunoreactive intensity of CCK and PRL had a positive linear correlation in cerebral cortex of HS group ( Y = 7. 939 +1. 36X, r = 0. 97, P < 0. 01), but no correlation was found in cerebral cortex of FC group ( r = 0. 47, P >0.05). Conclusion (1) CCK may involve in anti-convulsant mechanisms in response to FC. (2) There may be a synergistic action of PRL and CCK in the central control of HS.%目的 探讨急性热应激(HS)和热性惊厥(FC)对大脑皮层胆囊收缩素(CCK)和催乳素(PRL)定位表达的影响.方法 采用热水浴诱导21 日龄大鼠FC模型,应用免疫组织化学技术,对HS和FC大鼠CCK和PRL在大脑皮层的定位表达进行比较分析.结果 (1)HS组CCK和PRL阳性细胞在大脑皮层分布极为相似,免疫染色有共深或共浅的倾向.(2)HS组和FC组大脑皮层CCK、PRL阳性细胞数明显高于对照组(P<0.01).FC组大鼠大脑皮层各区CCK阳性细胞数明显高于HS组(P<0.01).FC组大鼠大

  3. Protective effect of Angelica sinensis on cerebral neurons from rat embryos under hypoxia

    Institute of Scientific and Technical Information of China (English)

    Yuling Wu; Hongxian Zhao; Hong Yu

    2007-01-01

    BACKGROUND: The enhanced expression of c-Fos protein in nerve cells after hypoxia is the marker for converting extracellular hypoxia information to intracellular changes at hypoxia, and it is suspected that the increase of c-Fos protein can lead to the synthesis and excretion of related neurotrophic factor and nerve growth factor. However, it is still unclear what functional changes of nerve cells are induced by the increase of c-Fos protein at hypoxia, and whether it is good for the survival of damaged neurons.OBJECTIVE: To observe the expression of c-Fos in the cerebral neurons from embryos of rats with hypoxia in uterus, and investigate the pathway for the protective effect of Angelica sinensis injection on the cerebral neurons from rat embryos under hypoxia.DESIGN: A completely randomized controlled study.SETTING: Department of Histology and Embryology, Luzhou Medical College.MATERIALS: Twelve female Wistar rats in oestrum and 1 male adult Wistar rat with body mass of 220 to 250 g were selected. Rabbit-anti-rat neuro-specific enolase (NSE) and rabbit-anti-rat c-Fos were purchased from Wuhan Boster Biological Technology Co., Ltd.; Double-staining kit was bought from Beijing Zhongshan Golden Bridge Biotechnology Co., Ltd. Angelica sinensis injection was produced by the Department of Pharmacy, the Second Affiliated Hospital of Hubei Medical University.METHODS: The experiments were completed in the experimental animal center and the Department of Histology and Embryology of Luzhou Medical College from December 2004 to December 2005. ① Twelve adult female Wistar rats in oestrum and 1 male Wistar rat were housed in one rearing cage. The appearance of vaginal embolus at 8:00 in the next morning was recorded as 0 day of pregnancy and the rats were recorded for 15 days, and they were divided randomly into three groups, control group (n =4), hypoxia group (n =4)and Angelica group (n =4). The pregnant rats in the hypoxia group were firstly injected with saline (8 m

  4. Wnt Signaling Regulates Multipolar-to-Bipolar Transition of Migrating Neurons in the Cerebral Cortex

    OpenAIRE

    Michael Boitard; Riccardo Bocchi; Kristof Egervari; Volodymyr Petrenko; Beatrice Viale; Stéphane Gremaud; Eloisa Zgraggen; Patrick Salmon; Jozsef Z. Kiss

    2015-01-01

    The precise timing of pyramidal cell migration from the ventricular germinal zone to the cortical plate is essential for establishing cortical layers, and migration errors can lead to neurodevelopmental disorders underlying psychiatric and neurological diseases. Here, we report that Wnt canonical as well as non-canonical signaling is active in pyramidal precursors during radial migration. We demonstrate using constitutive and conditional genetic strategies that transient downregulation of can...

  5. Visual space and object space in the cerebral cortex of retinal disease patients.

    Directory of Open Access Journals (Sweden)

    Elfi Goesaert

    Full Text Available The lower areas of the hierarchically organized visual cortex are strongly retinotopically organized, with strong responses to specific retinotopic stimuli, and no response to other stimuli outside these preferred regions. Higher areas in the ventral occipitotemporal cortex show a weak eccentricity bias, and are mainly sensitive for object category (e.g., faces versus buildings. This study investigated how the mapping of eccentricity and category sensitivity using functional magnetic resonance imaging is affected by a retinal lesion in two very different low vision patients: a patient with a large central scotoma, affecting central input to the retina (juvenile macular degeneration, and a patient where input to the peripheral retina is lost (retinitis pigmentosa. From the retinal degeneration, we can predict specific losses of retinotopic activation. These predictions were confirmed when comparing stimulus activations with a no-stimulus fixation baseline. At the same time, however, seemingly contradictory patterns of activation, unexpected given the retinal degeneration, were observed when different stimulus conditions were directly compared. These unexpected activations were due to position-specific deactivations, indicating the importance of investigating absolute activation (relative to a no-stimulus baseline rather than relative activation (comparing different stimulus conditions. Data from two controls, with simulated scotomas that matched the lesions in the two patients also showed that retinotopic mapping results could be explained by a combination of activations at the stimulated locations and deactivations at unstimulated locations. Category sensitivity was preserved in the two patients. In sum, when we take into account the full pattern of activations and deactivations elicited in retinotopic cortex and throughout the ventral object vision pathway in low vision patients, the pattern of (deactivation is consistent with the retinal loss.

  6. On the Parallel Between Zipf's Law and 1/f Processes\\in Chaotic Systems Possessing Coexisting Attractors --A Possible Mechanism for language Formation in the Cerebral Cortex--

    Science.gov (United States)

    Nicolis, J. S.; Tsuda, I.

    1989-08-01

    A chaotic dynamics model of creating Markovian strings of symbols as well as sequences of "words" is exposed, and its relevance to Zipf's law in experimental linguistics is discussed. Recent developments of brain science and linguistics suggest a preliminary theory of language formation by means of chaotic dynamics both in groups of cerebral neurons and the thalamocortical pacemaker itself.

  7. Region-specific maturation of cerebral cortex in human fetal brain: diffusion tensor imaging and histology

    Energy Technology Data Exchange (ETDEWEB)

    Trivedi, Richa; Gupta, Rakesh K.; Saksena, Sona [Sanjay Gandhi Post Graduate Institute of Medical Sciences, Department of Radiodiagnosis, Lucknow, UP (India); Husain, Nuzhat; Srivastava, Savita [CSM Medical University, Department of Pathology, Lucknow (India); Rathore, Ram K.S.; Sarma, Manoj K. [Indian Institute of Technology, Department of Mathematics and Statistics, Kanpur (India); Malik, Gyanendra K. [CSM Medical University, Department of Pediatrics, Lucknow (India); Das, Vinita [CSM Medical University, Department of Obstetrics and Gynecology, Lucknow (India); Pradhan, Mandakini [Sanjay Gandhi Postgraduate Institute of Medical Sciences, Department of Medical Genetics, Lucknow (India); Pandey, Chandra M. [Sanjay Gandhi Postgraduate Institute of Medical Sciences, Department of Biostatistics, Lucknow (India); Narayana, Ponnada A. [University of Texas Medical School at Houston, Department of Diagnostic and Interventional Imaging, Houston, TX (United States)

    2009-09-15

    In this study, diffusion tensor imaging (DTI) and glial fibrillary acidic protein (GFAP) immunohistochemical analysis in different cortical regions in fetal brains at different gestational age (GA) were performed. DTI was performed on 50 freshly aborted fetal brains with GA ranging from 12 to 42 weeks to compare age-related fractional anisotropy (FA) changes in different cerebral cortical regions that include frontal, parietal, occipital, and temporal lobes at the level of thalami. GFAP immunostaining was performed and the percentage of GFAP-positive areas was quantified. The cortical FA values in the frontal lobe peaked at around 26 weeks of GA, occipital and temporal lobes at around 20 weeks, and parietal lobe at around 23 weeks. A significant, but modest, positive correlation (r=0.31, p=0.02) was observed between cortical FA values and percentage area of GFAP expression in cortical region around the time period during which the migrational events are at its peak, i.e., GA {<=} 28 weeks for frontal cortical region and GA{<=}22 weeks for rest of the lobes. The DTI-derived FA quantification with its GFAP immunohistologic correlation in cortical regions of the various lobes of the cerebral hemispheres supports region-specific migrational and maturational events in human fetal brain. (orig.)

  8. Culturated rat cerebral cortex explants and their application in the study of SPECT scan radiopharaceuticals

    International Nuclear Information System (INIS)

    In this thesis mechanics that result in the distinct localization of radiopharmaceuticals within the brain have been investigated. In order to 'get more insight' in uptake and binding of radiopharmaceuticals bu brain tissue, use has been made of the tissue culture technique. Tissue culture privides the opportunity of doing experiments with brain tissue under stable conditions, in the absence of a blood-brain barrier, and without interference by cerebral blood flow. The present thesis is presented in two sections. The first part focusses on longterm culture of 'organotypic' cerebral neocortex tissue, obtained from neonatal rat brain and explanted into a chemically defined medium. Procedures were developed which enabled culturing of this tissue without the occurence of central necrosis and with the preservation of a characteristic histiotypic organization. Morphological characteristics of the cultures were described and measured at various ages in vitro. In the second part, the cultures were used to study mechanisms that might contribute to the tissue uptake of radiopharmaceuticals which are in clinical use for SPECT brain imaging. (author). 369 refs.; 50 figs.; 13 tabs

  9. Cortical neurogenesis in adult rats after ischemic brain injury:most new neurons fail to mature

    Institute of Scientific and Technical Information of China (English)

    Qing-quan Li; Guan-qun Qiao; Jun Ma; Hong-wei Fan; Ying-bin Li

    2015-01-01

    The present study examines the hypothesis that endogenous neural progenitor cells isolated from the neocortex of ischemic brain can differentiate into neurons or glial cells and contribute to neural regeneration. We performed middle cerebral artery occlusion to establish a model of cerebral ischemia/reperfusion injury in adult rats. Immunohistochemical staining of the cortex 1, 3, 7, 14 or 28 days after injury revealed that neural progenitor cells double-positive for nestin and sox-2 appeared in the injured cortex 1 and 3 days post-injury, and were also positive for glial ifbrillary acidic protein. New neurons were labeled using bromodeoxyuridine and different stages of maturity were identiifed using doublecortin, microtubule-associated protein 2 and neuronal nuclei antigen immunohistochemistry. Immature new neurons coexpressing doublecortin and bromodeoxyuridine were observed in the cortex at 3 and 7 days post-injury, and semi-mature and mature new neurons double-positive for microtubule-associated protein 2 and bromode-oxyuridine were found at 14 days post-injury. A few mature new neurons coexpressing neuronal nuclei antigen and bromodeoxyuridine were observed in the injured cortex 28 days post-injury. Glial ifbrillary acidic protein/bromodeoxyuridine double-positive astrocytes were also found in the injured cortex. Our ifndings suggest that neural progenitor cells are present in the damaged cortex of adult rats with cerebral ischemic brain injury, and that they differentiate into astrocytes and immature neurons, but most neurons fail to reach the mature stage.

  10. [Multiscale functional imaging: reconstructing network dynamics from the synaptic echoes recorded in a single visual cortex neuron].

    Science.gov (United States)

    Fregnac, Yves; Baudot, Pierre; Chavane, Frédéric; Marre, Olivier; Monier, Cyril; Pananceau, Marc; Sadoc, Gérard

    2009-04-01

    In vivo intracellular electrophysiology offers the unique possibility of listening to the "synaptic rumor " of the cortical network, captured by a recording electrode in a single V1 cell. It allows one to reconstruct the distribution of input sources in space and time, i.e. the effective network dynamics. We have used a reverse engineering method to demonstrate the propagation of visually evoked activity through lateral (and feedback) connectivity in the primary cortex of higher mammals. This approach, based on synaptic echography, is compared here with a real-time brain imaging technique based on voltage-sensitive dye imaging. The former method gives access to the microscopic convergence processes of single neurons, whereas the latter describes the macroscopic divergence process on the neuronal map. A combination of the two techniques can be used to elucidate the cortical origin of low-level (non attentive) binding processes participating in the emergence of Gestalt percepts. PMID:20120274

  11. Selective expression of KCNS3 potassium channel α-subunit in parvalbumin-containing GABA neurons in the human prefrontal cortex.

    Directory of Open Access Journals (Sweden)

    Danko Georgiev

    Full Text Available The cognitive deficits of schizophrenia appear to be associated with altered cortical GABA neurotransmission in the subsets of inhibitory neurons that express either parvalbumin (PV or somatostatin (SST. Identification of molecular mechanisms that operate selectively in these neurons is essential for developing targeted therapeutic strategies that do not influence other cell types. Consequently, we sought to identify, in the human cortex, gene products that are expressed selectively by PV and/or SST neurons, and that might contribute to their distinctive functional properties. Based on previously reported expression patterns in the cortex of mice and humans, we selected four genes: KCNS3, LHX6, KCNAB1, and PPP1R2, encoding K(+ channel Kv9.3 modulatory α-subunit, LIM homeobox protein 6, K(+ channel Kvβ1 subunit, and protein phosphatase 1 regulatory subunit 2, respectively, and examined their colocalization with PV or SST mRNAs in the human prefrontal cortex using dual-label in situ hybridization with (35S- and digoxigenin-labeled antisense riboprobes. KCNS3 mRNA was detected in almost all PV neurons, but not in SST neurons, and PV mRNA was detected in >90% of KCNS3 mRNA-expressing neurons. LHX6 mRNA was detected in almost all PV and >90% of SST neurons, while among all LHX6 mRNA-expressing neurons 50% expressed PV mRNA and >44% expressed SST mRNA. KCNAB1 and PPP1R2 mRNAs were detected in much larger populations of cortical neurons than PV or SST neurons. These findings indicate that KCNS3 is a selective marker of PV neurons, whereas LHX6 is expressed by both PV and SST neurons. KCNS3 and LHX6 might be useful for characterizing cell-type specific molecular alterations of cortical GABA neurotransmission and for the development of novel treatments targeting PV and/or SST neurons in schizophrenia.

  12. Selective expression of KCNS3 potassium channel α-subunit in parvalbumin-containing GABA neurons in the human prefrontal cortex.

    Science.gov (United States)

    Georgiev, Danko; González-Burgos, Guillermo; Kikuchi, Mitsuru; Minabe, Yoshio; Lewis, David A; Hashimoto, Takanori

    2012-01-01

    The cognitive deficits of schizophrenia appear to be associated with altered cortical GABA neurotransmission in the subsets of inhibitory neurons that express either parvalbumin (PV) or somatostatin (SST). Identification of molecular mechanisms that operate selectively in these neurons is essential for developing targeted therapeutic strategies that do not influence other cell types. Consequently, we sought to identify, in the human cortex, gene products that are expressed selectively by PV and/or SST neurons, and that might contribute to their distinctive functional properties. Based on previously reported expression patterns in the cortex of mice and humans, we selected four genes: KCNS3, LHX6, KCNAB1, and PPP1R2, encoding K(+) channel Kv9.3 modulatory α-subunit, LIM homeobox protein 6, K(+) channel Kvβ1 subunit, and protein phosphatase 1 regulatory subunit 2, respectively, and examined their colocalization with PV or SST mRNAs in the human prefrontal cortex using dual-label in situ hybridization with (35)S- and digoxigenin-labeled antisense riboprobes. KCNS3 mRNA was detected in almost all PV neurons, but not in SST neurons, and PV mRNA was detected in >90% of KCNS3 mRNA-expressing neurons. LHX6 mRNA was detected in almost all PV and >90% of SST neurons, while among all LHX6 mRNA-expressing neurons 50% expressed PV mRNA and >44% expressed SST mRNA. KCNAB1 and PPP1R2 mRNAs were detected in much larger populations of cortical neurons than PV or SST neurons. These findings indicate that KCNS3 is a selective marker of PV neurons, whereas LHX6 is expressed by both PV and SST neurons. KCNS3 and LHX6 might be useful for characterizing cell-type specific molecular alterations of cortical GABA neurotransmission and for the development of novel treatments targeting PV and/or SST neurons in schizophrenia.

  13. Optogenetic micro-electrocorticography for modulating and localizing cerebral cortex activity

    Science.gov (United States)

    Richner, Thomas J.; Thongpang, Sanitta; Brodnick, Sarah K.; Schendel, Amelia A.; Falk, Ryan W.; Krugner-Higby, Lisa A.; Pashaie, Ramin; Williams, Justin C.

    2014-02-01

    Objective. Spatial localization of neural activity from within the brain with electrocorticography (ECoG) and electroencephalography remains a challenge in clinical and research settings, and while microfabricated ECoG (micro-ECoG) array technology continues to improve, complementary methods to simultaneously modulate cortical activity while recording are needed. Approach. We developed a neural interface utilizing optogenetics, cranial windowing, and micro-ECoG arrays fabricated on a transparent polymer. This approach enabled us to directly modulate neural activity at known locations around micro-ECoG arrays in mice expressing Channelrhodopsin-2. We applied photostimuli varying in time, space and frequency to the cortical surface, and we targeted multiple depths within the cortex using an optical fiber while recording micro-ECoG signals. Main results. Negative potentials of up to 1.5 mV were evoked by photostimuli applied to the entire cortical window, while focally applied photostimuli evoked spatially localized micro-ECoG potentials. Two simultaneously applied focal stimuli could be separated, depending on the distance between them. Photostimuli applied within the cortex with an optical fiber evoked more complex micro-ECoG potentials with multiple positive and negative peaks whose relative amplitudes depended on the depth of the fiber. Significance. Optogenetic ECoG has potential applications in the study of epilepsy, cortical dynamics, and neuroprostheses.

  14. Effects of Ketamine on Neuronal Spontaneous Excitatory Postsynaptic Currents and Miniature Excitatory Postsynaptic Currents in the Somatosensory Cortex of Rats

    Directory of Open Access Journals (Sweden)

    Chengdong Yuan

    2016-07-01

    Full Text Available Background: Ketamine is a commonly used intravenous anesthetic which produces dissociation anesthesia, analgesia, and amnesia. The mechanism of ketamine-induced synaptic inhibition in high-level cortical areas is still unknown. We aimed to elucidate the effects of different concentrations of ketamine on the glutamatergic synaptic transmission of the neurons in the primary somatosensory cortex by using the whole-cell patch-clamp method. Methods: Sprague-Dawley rats (11–19 postnatal days, n=36 were used to obtain brain slices (300 μM. Spontaneous excitatory postsynaptic currents (data from 40 neurons were recorded at a command potential of -70 mV in the presence of bicuculline (a competitive antagonist of GABAA receptors, 30 μM and strychnine (glycine receptor antagonist, 30 μM. Miniature excitatory postsynaptic currents (data from 40 neurons were also recorded when 1 μM of tetrodotoxin was added into the artificial cerebrospinal fluid. We used GraphPad Prism5for statistical analysis. Significant differences in the mean amplitude and frequency were tested using the Student paired 2-tailed t test. Values of P<0.05 were considered significant. Results: Different concentrations of ketamine inhibited the frequency and amplitude of the spontaneous excitatory postsynaptic currents as well as the amplitude of the miniature excitatory postsynaptic currents in a concentration-dependent manner, but they exerted no significant effect on the frequency of the miniature excitatory postsynaptic currents. Conclusion: Ketamine inhibited the excitatory synaptic transmission of the neurons in the primary somatosensory cortex. The inhibition may have been mediated by a reduction in the sensitivity of the postsynaptic glutamatergic receptors.

  15. Binocular neurons in parastriate cortex: interocular 'matching' of receptive field properties, eye dominance and strength of silent suppression.

    Directory of Open Access Journals (Sweden)

    Phillip A Romo

    Full Text Available Spike-responses of single binocular neurons were recorded from a distinct part of primary visual cortex, the parastriate cortex (cytoarchitectonic area 18 of anaesthetized and immobilized domestic cats. Functional identification of neurons was based on the ratios of phase-variant (F1 component to the mean firing rate (F0 of their spike-responses to optimized (orientation, direction, spatial and temporal frequencies and size sine-wave-luminance-modulated drifting grating patches presented separately via each eye. In over 95% of neurons, the interocular differences in the phase-sensitivities (differences in F1/F0 spike-response ratios were small (≤ 0.3 and in over 80% of neurons, the interocular differences in preferred orientations were ≤ 10°. The interocular correlations of the direction selectivity indices and optimal spatial frequencies, like those of the phase sensitivies and optimal orientations, were also strong (coefficients of correlation r ≥ 0.7005. By contrast, the interocular correlations of the optimal temporal frequencies, the diameters of summation areas of the excitatory responses and suppression indices were weak (coefficients of correlation r ≤ 0.4585. In cells with high eye dominance indices (HEDI cells, the mean magnitudes of suppressions evoked by stimulation of silent, extra-classical receptive fields via the non-dominant eyes, were significantly greater than those when the stimuli were presented via the dominant eyes. We argue that the well documented 'eye-origin specific' segregation of the lateral geniculate inputs underpinning distinct eye dominance columns in primary visual cortices of mammals with frontally positioned eyes (distinct eye dominance columns, combined with significant interocular differences in the strength of silent suppressive fields, putatively contribute to binocular stereoscopic vision.

  16. aequorine bioluminescence response to calcium in vitro and in cerebral cortex

    OpenAIRE

    Tricoire, Ludovic

    2006-01-01

    During my PhD, I investigated in vitro the calcium-dependent bioluminescence of thephotoprotein aequorin and then used its bioluminescence to image neuronal activities in theneocortical network. This genetically encoded calcium sensor can be expressed in specific cell types and its bioluminescence is not toxic and exhibit a high signal/noise ratio.I first search for mutations modifying aequorin bioluminescence, using a randommutagenesis and in vitro evolution approach. I isolated mutants show...

  17. Developmental malformations of the cerebral cortex; Heterotopie, Polymikrogyrie, Lissenzephalie und Co. Malformationen der kortikalen Hirnentwicklung

    Energy Technology Data Exchange (ETDEWEB)

    Reiss-Zimmermann, Martin [Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie, Universitaetsklinikum Leipzig AoeR (Germany); Weber, D.; Sorge, I.; Hirsch, W. [Abt. Paediatrische Radiologie, Universitaetsklinikum Leipzig AoeR (Germany); Merkenschlager, A. [Universitaetsklinik und Poliklinik fuer Kinder und Jugendliche, Universitaetsklinikum Leipzig AoeR (Germany)

    2010-06-15

    Migration disorders (MD) are increasingly recognized as an important cause of epilepsy and developmental delay. Up to 25% of children with refractory epilepsy have a cortical malformation. MD encompass a wide spectrum with underlying genetic etiologies and clinical manifestations. Research regarding the delineation of the genetic and molecular basis of these disorders has provided greater insight into the pathogenesis of not only the malformation but also the process involved in normal cortical development. Diagnosis of MD is important since patients who fail three antiepileptic medications are less likely to have their seizures controlled with additional trials of medications and therefore epilepsy surgery should be considered. Recent improvements in neuroimaging have resulted in a significant increase in the recognition of MD. Findings can be subdivided in disorders due to abnormal neurogenesis, neuronal migration, neuronal migration arrest and neuronal organization resulting in different malformations like microcephaly, lissencephaly, schizencephaly and heterotopia. The examination protocol should include T1-w and T2-w sequences in adequate slice orientation. T1-w turbo-inversion recovery sequences (TIR) can be helpful to diagnose heterotopia. Contrast agent is needed only to exclude other differential diagnoses. (orig.)

  18. Alterations in neuronal morphology in infralimbic cortex predict resistance to fear extinction following acute stress.

    Science.gov (United States)

    Moench, Kelly M; Maroun, Mouna; Kavushansky, Alexandra; Wellman, Cara

    2016-06-01

    Dysfunction in corticolimbic circuits that mediate the extinction of learned fear responses is thought to underlie the perseveration of fear in stress-related psychopathologies, including post-traumatic stress disorder. Chronic stress produces dendritic hypertrophy in basolateral amygdala (BLA) and dendritic hypotrophy in medial prefrontal cortex, whereas acute stress leads to hypotrophy in both BLA and prelimbic cortex. Additionally, both chronic and acute stress impair extinction retrieval. Here, we examined the effects of a single elevated platform stress on extinction learning and dendritic morphology in infralimbic cortex, a region considered to be critical for extinction. Acute stress produced resistance to extinction, as well as dendritic retraction in infralimbic cortex. Spine density on apical and basilar terminal branches was unaffected by stress. However, animals that underwent conditioning and extinction had decreased spine density on apical terminal branches. Thus, whereas dendritic morphology in infralimbic cortex appears to be particularly sensitive to stress, changes in spines may more sensitively reflect learning. Further, in stressed rats that underwent conditioning and extinction, the level of extinction learning was correlated with spine densities, in that rats with poorer extinction retrieval had more immature spines and fewer thin spines than rats with better extinction retrieval, suggesting that stress may have impaired learning-related spine plasticity. These results may have implications for understanding the role of medial prefrontal cortex in learning deficits associated with stress-related pathologies. PMID:26844245

  19. Quantified regional and laminar distribution of the noradrenaline innervation in the anterior half of the adult rat cerebral cortex

    Energy Technology Data Exchange (ETDEWEB)

    Audet, M.A.; Doucet, G.; Oleskevich, S.; Descarries, L.

    1988-08-15

    The regional and laminar distribution of the noradrenaline (NA) innervation in the adult rat cerebral cortex was quantified in radioautographs of semithin sections from whole hemisphere slices incubated with tritiated catecholamines and a monoamine oxidase inhibitor. Uptake-labeled axonal varicosities (aggregates of silver grains) were counted with the help of a computerized image analyzer in seven cytoarchitectonic areas of the rostral half of the cortex: Cg3, rostral AID, Cg2, Fr1, Par1, caudal AID, and Pir (prepiriform) according to Zilles's nomenclature. Both dopamine (DA) and NA terminals were detected after incubation with (3H)DA and citalopram or with (3H)NA alone. In the presence of desipramine (DMI), DA terminals alone were demonstrated; the number of NA terminals was then obtained by subtraction from counts in adjacent slices incubated with or without DMI. These counts suggested that DA and NA varicosities were fully visualized only after labeling with their respective tritiated amine. Similar numbers of labeled NA varicosities as inferred after (3H)NA incubation with or without DMI were observed after (3H)NA incubation in the presence of benztropine (BZ). This indicated that NA terminals were then maximally detected to the exclusion of the DA ones, and the latter approach was adopted for the acquisition of normative data. Since the average diameter of the labeled NA varicosities was known from earlier measurements in electron microscope radioautographs, the initial counts of labeled sites/mm2 of histological section could be expressed as numbers of varicosities/mm3 of tissue following a double correction for incomplete detection at the chosen duration of radioautographic exposure and section thickness.

  20. Localization of Nitric Oxide Synthase-containing Neurons in the Bat Visual Cortex and Co-localization with Calcium-binding Proteins

    International Nuclear Information System (INIS)

    Microchiroptera (microbats) is a suborder of bats thought to have degenerated vision. However, many recent studies have shown that they have visual ability. In this study, we labeled neuronal nitric oxide synthase (nNOS)—the synthesizing enzyme of the gaseous non-synaptic neurotransmitter nitric oxide—and co-localized it with calbindin D28K (CB), calretinin (CR), and parvalbumin (PV) in the visual cortex of the greater horseshoe bat (Rhinolophus ferrumequinum, a species of microbats). nNOS-immunoreactive (IR) neurons were found in all layers of the visual cortex. Intensely labeled neurons were most common in layer IV, and weakly labeled neurons were most common in layer VI. Majority of the nNOS-IR neurons were round- or oval-type neurons; no pyramidal-type neurons were found. None of these neurons co-localized with CB, CR, or PV. However, the synthesis of nitric oxide in the bat visual cortex by nNOS does not depend on CB, CR, or PV

  1. DHA improves cognition and prevents dysfunction of entorhinal cortex neurons in 3xTg-AD mice.

    Directory of Open Access Journals (Sweden)

    Dany Arsenault

    Full Text Available Defects in neuronal activity of the entorhinal cortex (EC are suspected to underlie the symptoms of Alzheimer's disease (AD. Whereas neuroprotective effects of docosahexaenoic acid (DHA have been described, the effects of DHA on the physiology of EC neurons remain unexplored in animal models of AD. Here, we show that DHA consumption improved object recognition (↑12%, preventing deficits observed in old 3xTg-AD mice (↓12%. Moreover, 3xTg-AD mice displayed seizure-like akinetic episodes, not detected in NonTg littermates and partly prevented by DHA (↓50%. Patch-clamp recording revealed that 3xTg-AD EC neurons displayed (i loss of cell capacitance (CC, suggesting reduced membrane surface area; (ii increase of firing rate versus injected current (F-I curve associated with modified action potentials, and (iii overactivation of glutamatergic synapses, without changes in synaptophysin levels. DHA consumption increased CC (↑12% and decreased F-I slopes (↓21%, thereby preventing the opposite alterations observed in 3xTg-AD mice. Our results indicate that cognitive performance and basic physiology of EC neurons depend on DHA intake in a mouse model of AD.

  2. Expression of constitutively active erythropoietin receptor in pyramidal neurons of cortex and hippocampus boosts higher cognitive functions in mice

    Directory of Open Access Journals (Sweden)

    Hassouna Imam

    2011-04-01

    Full Text Available Abstract Background Erythropoietin (EPO and its receptor (EPOR are expressed in the developing brain and their transcription is upregulated in adult neurons and glia upon injury or neurodegeneration. We have shown neuroprotective effects and improved cognition in patients with neuropsychiatric diseases treated with EPO. However, the critical EPO targets in brain are unknown, and separation of direct and indirect effects has remained difficult, given the role of EPO in hematopoiesis and brain oxygen supply. Results Here we demonstrate that mice with transgenic expression of a constitutively active EPOR isoform (cEPOR in pyramidal neurons of cortex and hippocampus exhibit enhancement of spatial learning, cognitive flexibility, social memory, and attentional capacities, accompanied by increased impulsivity. Superior cognitive performance is associated with augmented long-term potentiation of cEPOR expressing neurons in hippocampal slices. Conclusions Active EPOR stimulates neuronal plasticity independent of any hematopoietic effects and in addition to its neuroprotective actions. This property of EPOR signaling should be exploited for defining novel strategies to therapeutically enhance cognitive performance in disease conditions.

  3. Encoding of both positive and negative reward prediction errors by neurons of the primate lateral prefrontal cortex and caudate nucleus.

    Science.gov (United States)

    Asaad, Wael F; Eskandar, Emad N

    2011-12-01

    Learning can be motivated by unanticipated success or unexpected failure. The former encourages us to repeat an action or activity, whereas the latter leads us to find an alternative strategy. Understanding the neural representation of these unexpected events is therefore critical to elucidate learning-related circuits. We examined the activity of neurons in the lateral prefrontal cortex (PFC) and caudate nucleus of monkeys as they performed a trial-and-error learning task. Unexpected outcomes were widely represented in both structures, and neurons driven by unexpectedly negative outcomes were as frequent as those activated by unexpectedly positive outcomes. Moreover, both positive and negative reward prediction errors (RPEs) were represented primarily by increases in firing rate, unlike the manner in which dopamine neurons have been observed to reflect these values. Interestingly, positive RPEs tended to appear with shorter latency than negative RPEs, perhaps reflecting the mechanism of their generation. Last, in the PFC but not the caudate, trial-by-trial variations in outcome-related activity were linked to the animals' subsequent behavioral decisions. More broadly, the robustness of RPE signaling by these neurons suggests that actor-critic models of reinforcement learning in which the PFC and particularly the caudate are considered primarily to be "actors" rather than "critics," should be reconsidered to include a prominent evaluative role for these structures. PMID:22159094

  4. The facilitatory influence of anterior cingulate cortex on ON-OFF response of tactile neuron in thalamic ventrobasal nucleus

    Institute of Scientific and Technical Information of China (English)

    曹晓华; 卢湘岳; 周绍慈

    2000-01-01

    The structures of limbic system have been found to modulate the auditory, visual and pain afferent signals in the related nuclei of thalamus. One of those structures is anterior cingulate cortex (ACC) that influences nocuous response of the pain-sensitive neurons in the ventropos-tero-lateral nucleus of thalamus. Thus, we inferred that ACC would also modulate tactile information at the thalamic level. To test this assumption, single units were recorded extracellularly from thalamic ventrobasal nucleus (VB). Tactile ON-OFF response and the relationship between different patterns of the responses and the parameters of tactile stimulation were examined. Furthermore, the influence of ACC on the tactile ON-OFF response was studied. ACC stimulation was found to produce a facilitatory effect on the OFF-response of ON-OFF neurons. It lowered the threshold of the off-response of that neuron, and therefore changed the response pattern or enhanced the firing rate of the OFF-response of the neuron. The study on rec

  5. Hyperlipidemia affects neuronal nitric oxide synthase expression in brains of focal cerebral ischemia rat model

    Institute of Scientific and Technical Information of China (English)

    Jianji Pei; Liqiang Liu; Jinping Pang; Xiaohong Tian

    2008-01-01

    BACKGROUND: Hyperlipidemia, a risk factor for ischemic cerebrovascular disease, may mediate production of neuronal nitric oxide synthase (nNOS) to induce increased nitric oxide levels, resulting in brain neuronal injury. OBJECTIVE: To investigate effects of hyperlipidemia on brain nNOS expression, and to verify changes in infarct volume and pathology during reperfusion, as well as neuronal injury following ischemia/reperfusion in a rat model of focal cerebral ischemia. DESIGN, TIME AND SETTING: Complete, randomized grouping experiment was performed at the Laboratory of Physiology, Shanxi Medical University from March 2005 to March 2006. MATERIALS: A total of 144 eight-week-old, male, Wistar rats, weighing 160-180 g, were selected. A rat model of middle cerebral artery occlusion was established by suture method after 4 weeks of formulated diet. Nitric oxide kit and rabbit anti-rat nNOS kit were respectively purchased from Nanjing Jiancheng Bioengineering Institute, China and Wuhan Boster Biological Technology, Ltd., China. METHODS: The rats were equally and randomly divided into high-fat diet and a normal diet groups. Rats in the high-fat diet group were fed a high-fat diet, consisting of 10% egg yolk powder, 5% pork fat, and 0.5% pig bile salt combined with standard chow to create hyperlipidemia. Rats in the normal diet group were fed a standard rat chow. A total of 72 rats in both groups were randomly divided into 6 subgroups: sham-operated, 4-hour ischemia, 4-hour ischemia/2-hour reperfusion, 4-hour ischemia/4-hour reperfusion, 4-hour ischemia/6-hour reperfusion, and 4-hour ischemia/12-hour reperfusion, with 12 rats in each subgroup. MAIN OUTCOME MEASURES: nNOS expression was measured by immunohistochemistry, and pathomorphology changes were detected by hematoxylin-eosin staining. Infarct volume and nitric oxide levels were respectively measured using 2, 3, 5-triphenyltetrazolium chloride (TTC) and immunohistochemistry. RESULTS: In the ischemic region, pathology

  6. Role of mitochondrial calcium uniporter in regulating mitochondrial fission in the cerebral cortexes of living rats.

    Science.gov (United States)

    Liang, Nan; Wang, Peng; Wang, Shilei; Li, Shuhong; Li, Yu; Wang, Jinying; Wang, Min

    2014-06-01

    The mitochondrial calcium uniporter (MCU) transports Ca2+ from the cytoplasm to the mitochondrial matrix and thus maintains Ca2+ homeostasis. Previous studies have reported that inhibition of MCU by ruthenium red (RR) protects the brain from ischemia/reperfusion (I/R) injury and that mitochondrial fission plays an important role in I/R injury. However, it is still not known whether MCU affects mitochondrial fission. In the present study, treatment with RR was found to decrease the concentration of free calcium in the mitochondria, calcineurin enzyme activity and dynamin-related protein 1 expression, and treatment with spermine was found to have the opposite effect in organisms subjected to occlusion of the middle cerebral artery lasting 2 h followed by 24 h reperfusion. These results indicate that MCU may be related to mitochondrial fission via modulating mitochondrial Ca2+ uptake and this relationship between MCU and mitochondrial fission may protect the brain from I/R injury.

  7. Focal increase of blood flow in the cerebral cortex of man during vestibular stimulation

    DEFF Research Database (Denmark)

    Friberg, L; Olsen, T S; Roland, P E;

    1985-01-01

    This study is an attempt to reveal projection areas for vestibular afferents to the human brain. Changes in regional cerebral blood flow (rCBF) were measured over 254 cortical regions during caloric vestibular stimulation with warm water (44 degrees C). rCBF was measured when the external auditory...... meatus was irrigated with water at body temperature as a control to vestibular stimulation. During vestibular stimulation there was only a single cortical area, located in the superior temporal region, which showed a consistent focal activation in the hemisphere contralateral to the stimulated side....... On the rCBF display this area was located in the superior temporal region posterior to the auditory area, probably in the superior temporal gyrus. It is suggested that this area represents the primary projection area of the vestibular nerve and that it is the activation of this area during caloric...

  8. 被动运动加氦-氖激光治疗急性脑梗死偏瘫50例%50 cases of acute cerebral infarction treated with passive exercise and Heli-um-neon laser

    Institute of Scientific and Technical Information of China (English)

    赵政凯; 杨东妮

    2003-01-01

    @@ BACKGROUND: Passive exercise can promote plastic de-velopment of cerebral cortex function with afferent stimuli received by receptors and recover lost functions. Utility of Helium-neon laser can protect neurons.

  9. The expression of thyroid hormone transporters in the human fetal cerebral cortex during early development and in N-Tera-2 neurodifferentiation

    OpenAIRE

    Chan, S Y; Martín-Santos, A; Loubière, L.S.; González, A.M.; Stieger, B.; Logan, A; McCabe, C.J.; Franklyn, J A; Kilby, M. D.

    2011-01-01

    Associations of neurological impairment with mutations in the thyroid hormone (TH) transporter, MCT8, and with maternal hypothyroxinaemia, suggest that THs are crucial for human fetal brain development. It has been postulated that TH transporters regulate the cellular supply of THs within the fetal brain during development. This study describes the expression of TH transporters in the human fetal cerebral cortex (7–20 weeks gestation) and during retinoic acid induced neurodifferentiation of t...

  10. The steady-state response of the cerebral cortex to the beat of music reflects both the comprehension of music and attention

    OpenAIRE

    Meltzer, Benjamin; Reichenbach, Chagit S.; Braiman, Chananel; Nicholas D Schiff; Hudspeth, A J; Reichenbach, Tobias

    2015-01-01

    The brain’s analyses of speech and music share a range of neural resources and mechanisms. Music displays a temporal structure of complexity similar to that of speech, unfolds over comparable timescales, and elicits cognitive demands in tasks involving comprehension and attention. During speech processing, synchronized neural activity of the cerebral cortex in the delta and theta frequency bands tracks the envelope of a speech signal, and this neural activity is modulated by high-level cortic...

  11. Asymmetric activation of the anterior cerebral cortex in recipients of IRECA: preliminary evidence for the energetic effects of an intention-based treatment modality on human neurophysiology.

    OpenAIRE

    Pike, C.; Vernon, D.; Hald, L.

    2014-01-01

    Objectives: Neurophysiologic studies of mindfulness link the health benefits of meditation to activation of the left-anterior cerebral cortex. The similarity and functional importance of intention and attentional stance in meditative and biofield therapeutic practices suggest that modulation of recipient anterior asymmetric activation may mediate the energetic effects of intention-based biofield treatments as well. The aim of the current study was to test this hypothesis by using a treatment ...

  12. Effects of percutaneous midband pulse current stimulation in hepatic region on free radical and nissl bodies in cerebral cortex of rats with exercise-induced fatigue

    OpenAIRE

    Zhang, Jia; Chang-lin HUANG

    2015-01-01

    Objective To investigate the effects of percutaneous midband pulse current stimulation in hepatic region on anti-exercise fatigue ability and the free radicals and nissl bodies in cerebral cortex tissue of rats with exercise-induced fatigue. Methods Seventy-two 8-week old male Wistar rats were randomly divided into 4 groups (18 each): control group (CG), fatigue group (FG), stimulation before fatigue group (SBF) and stimulation after fatigue group (SAF). Animals in FG, SBF and SAF group were ...

  13. The steady-state response of the cerebral cortex to the beat of music reflects both the comprehension of music and attention

    OpenAIRE

    Benjamin eMeltzer; Reichenbach, Chagit S.; Chananel eBraiman; Schiff, Nicholas D.; Hudspeth, A. J.; Tobias eReichenbach

    2015-01-01

    The brain's analyses of speech and music share a range of neural resources and mechanisms. Music displays a temporal structure of complexity similar to that of speech, unfolds over comparable timescales, and elicits cognitive demands in tasks involving comprehension and attention. During speech processing, synchronized neural activity of the cerebral cortex in the delta and theta frequency bands tracks the envelope of a speech signal, and this neural activity is modulated by high-level cortic...

  14. Effects of Chloroquine on GFAP, PCNA and Cyclin D1 in Hippocampus and Cerebral Cortex of Rats with Seizures Induced by Pentylenetetrazole

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shuhua; ZHU Changgeng; LIU Qingying; WANG Wei

    2005-01-01

    The effects of chloroquine on glial fibrillary acidic protein (GFAP), proliferation cell nuclear antigen (PCNA) and Cyclin D1 in hippocampus and cerebral cortex of rats with seizures induced by pentylenetetrazole (PTZ) were observed in the present study. Forty-eight male adult Sprague-Dawley (SD) rats were randomly divided into control group, chloroquine intervening group, and PTZ group. The behavior and electroencephalogram (EEG) were observed and recor ded. GFAP and PCNA were examined with immunohistochemistry. The content of Cyclin D1 in hippocampus and cerebral cortex was inspected with Western blot. The results showed no seizure activity in the control group, severe seizure activity in the PTZ group (Ⅳ-Ⅴ degree), and slight seizure activity ( Ⅰ - Ⅲ degree) in the chloroquine intervening group (P<0. 05). EEG recordings showed no epileptic spikes in the control group, high amplitude with fast frequency in the PTZ group, low-amplitude and slow frequency in the chloroquine intervening group. The expression of GFAP and the positive index of PCNA in the PTZ group were higher than those of control group (P <0.05 and P<0.01, respectively). No differences in GFAP expression and PCNA index were observed between chloroquine intervening and control groups (P>0.05). The content of Cyclin D1 in hippocampus and cerebral cortex was significantly higher in the PTZ group than in control and chloroquine intervening groups (P< 0.05). Therefore, it is considered that chloroquine, by inhibiting the functions and proliferation of glial cells in the hippocampus and cerebral cortex, can alleviate the seizure activities. These results suggest that chloroquine may be an ideal anticonvulsant in preventing and treating epilepsy.

  15. Thickness of the Human Cerebral Cortex is Associated with Metrics of Cerebrovascular Health in a Normative Sample of Community Dwelling Older Adults

    OpenAIRE

    Leritz, Elizabeth C.; Salat, David H.; Williams, Victoria J.; Schnyer, David M.; Rudolph, James L.; Lipsitz, Lewis; Fischl, Bruce; McGlinchey, Regina E.; Milberg, William P.

    2010-01-01

    We examined how wide ranges in levels of risk factors for cerebrovascular disease are associated with thickness of the human cerebral cortex in 115 individuals ages 43–83 with no cerebrovascular or neurologic history. Cerebrovascular risk factors included blood pressure, cholesterol, body mass index, creatinine, and diabetes-related factors. Variables were submitted into a principal components analysis that confirmed four orthogonal factors (Blood Pressure, Cholesterol, Cholesterol/Metabolic ...

  16. Evaluation of Cerebral Cortex Function in Clients with Bipolar Mood Disorder I (BMD I) Compared With BMD II Using QEEG Analysis

    OpenAIRE

    Ali Khaleghi; Ali Sheikhani; MohammadReza Mohammadi; Ali Moti-Nasrabadi

    2015-01-01

    Objective: Early diagnosis of type I and type II bipolar mood disorder is very challenging particularly in adolescence. Hence, we aimed to investigate the cerebral cortex function in these patients, using quantitative electroencephalography analysis to obtain significant differences between them.Methods: Thirty- eight adolescents (18 patients with bipolar disorder I and 20 with BMD II) participated in this study. We recorded the electroencephalogram signals based on 10-20 international system...

  17. Improving effect of Ginkgolide B on mitochondrial respiration of ischemic neuron after cerebral thrombosis in tree shrews

    Institute of Scientific and Technical Information of China (English)

    LI Shu-qing; ZHANG Ying; YANG Li-jun

    2007-01-01

    Background It has been known that platelet activating factor receptors (PAFR) may mediate many acute pathological responses and that PAFR antagonist Ginkgolide B (GB) possesses multiple effects, but the actions of GB on PAFR affinity and mitochondrial respiration in the ischemic neuron were unclear until now. This study explored the possible effects of GB on PAFR and the mitochondrial respiration of the neuron in the ischemic microenvironment.Methods Thrombotic cerebral ischemia in tree shrews was induced by a photochemical reaction; changes in the regional cerebral blood flow (rCBF, using 99mTc tracer technique ), the brain water content (specific gravimetric method), PAFR (3H-labelled PAF assay), the respiratory control rate (RCR), the phosphorus-oxygen (P/O) ratio of mitochondrial respiration (Clark oxygen electrode), mitochondrial permeability transition (MPT) pore, and the mitochondrial ultrastructure in the ischemic neurons were also observed. Data were compared between the two groups (the ischemia group vs the sham group, and the ischemia group vs the GB group).Results There were high affinity and low affinity sites for PAFR on the tree threws' brain cell membranes. The varying-affinity PAFR binding sites, the respiration state Ⅲ, the state Ⅳ, RCR, the P/O ratio of the mitochondria, and the rCBF all decreased markedly (respectively, P<0.01 and P<0.05), but the water content increased (P<0.01) in the ischemia group after the application of cerebral thrombosis. In tree shrews treated with GB (5 mg/kg I.v.) 6 hours after photochemical reaction, their PAFR binding sites and respiratory state increased markedly. The rCBF gradually increased and the brain edema ameliorated (P<0.01) at 24h after cerebral ischemia. There were significant differences between the ischemia group and sham group (P<0.01). In GB treated isolated neurons' mitochondria, with or without cerebral ischemia, the energy metabolism of the mitochondria had not been changed

  18. Creatine and pyruvate prevent the alterations caused by tyrosine on parameters of oxidative stress and enzyme activities of phosphoryltransfer network in cerebral cortex of Wistar rats.

    Science.gov (United States)

    de Andrade, Rodrigo Binkowski; Gemelli, Tanise; Rojas, Denise Bertin; Bonorino, Narielle Ferner; Costa, Bruna May Lopes; Funchal, Cláudia; Dutra-Filho, Carlos Severo; Wannmacher, Clovis Milton Duval

    2015-01-01

    Tyrosine accumulates in inborn errors of tyrosine catabolism, especially in tyrosinemia type II. In this disease caused by tyrosine aminotransferase deficiency, eyes, skin, and central nervous system disturbances are found. In the present study, we investigated the chronic effect of tyrosine methyl ester (TME) and/or creatine plus pyruvate on some parameters of oxidative stress and enzyme activities of phosphoryltransfer network in cerebral cortex homogenates of 21-day-old Wistar. Chronic administration of TME induced oxidative stress and altered the activities of adenylate kinase and mitochondrial and cytosolic creatine kinase. Total sulfhydryls content, GSH content, and GPx activity were significantly diminished, while DCFH oxidation, TBARS content, and SOD activity were significantly enhanced by TME. On the other hand, TME administration decreased the activity of CK from cytosolic and mitochondrial fractions but enhanced AK activity. In contrast, TME did not affect the carbonyl content and PK activity in cerebral cortex of rats. Co-administration of creatine plus pyruvate was effective in the prevention of alterations provoked by TME administration on the oxidative stress and the enzymes of phosphoryltransfer network, except in mitochondrial CK, AK, and SOD activities. These results indicate that chronic administration of TME may stimulate oxidative stress and alter the enzymes of phosphoryltransfer network in cerebral cortex of rats. In case this also occurs in the patients affected by these disorders, it may contribute, along with other mechanisms, to the neurological dysfunction of hypertyrosinemias, and creatine and pyruvate supplementation could be beneficial to the patients.

  19. Expression of estrogen receptor (ER) -α and -β transcripts in the neonatal and adult rat cerebral cortex, cerebellum, and olfactory bulb

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In the present study expression of estrogen receptor subtype -α (ERα) and -β (ERβ) in the cerebral cortex, cerebellum, and olfactory bulb was investigated and compared between neonatal (1~ 3-days-old) and adult (250~350g) rats, using reverse transcription-polymerase chain reaction (RT-PCR). No ERα transcripts were detectable in the adult cerebellum and olfactory bulb, whereas very weak expression of ERα was present in the adult cerebral cortex. No significant difference in ERβ transcripts was detectable between the neonatal and adult rats. While transcripts for both ER subtypes were co-expressed in these brain areas of neonatal rats, although ERα expression was significantly weaker than ERβ. Even in the cerebral cortex known to contain both ER subtypes in adult rats, ERα transcripts in neonatal rats were much higher than in adult. These observations provide evidence for the existence of different expression patterns of ERα/ERβ transcripts in these three brain areas between the neonatal and adult rats, suggesting that each ER subtype may play a distinct role in the regulation of differentiation, development, and functions of the brain by estrogen.

  20. GLT-1 promoter activity in astrocytes and neurons of mouse hippocampus and somatic sensory cortex

    Directory of Open Access Journals (Sweden)

    Luisa De Vivo

    2010-01-01

    Full Text Available GLT-1 eGFP BAC reporter transgenic adult mice were used to detect GLT-1 gene expression in individual cells of CA1, CA3 and SI, and eGFP fluorescence was measured to analyze quantitatively GLT-1 promoter activity in different cells of neocortex and hippocampus. Virtually all GFAP+ astrocytes were eGFP+; we also found that about 80% of neurons in CA3 pyramidal layer, 10-70% of neurons in I-VI layers of SI and rare neurons in all strata of CA1 and in strata oriens and radiatum of CA3 were eGFP+. Analysis of eGFP intensity showed that astrocytes had a higher GLT-1 promoter activity in SI than in CA1 and CA3, and that neurons had the highest levels of GLT-1 promoter activity in CA3 stratum pyramidale and in layer VI of SI. Finally, we observed that the intensity of GLT-1 promoter activity in neurons is 1-20% of that measured in astrocytes. These results showed that in the hippocampus and neocortex GLT-1 promoter activity is observed in astrocytes and neurons, detailed the distribution of GLT-1 expressing neurons, and indicated that GLT-1 promoter activity in both astrocytes and neurons varies in different brain regions.

  1. Structure of the cerebral cortex. Intrinsec organization and comparative analysis of the neocortex | Estructura de la corteza cerebral. Organización intrínseca y análisis comparativo del neocórtex

    OpenAIRE

    Valverde, Facundo

    2002-01-01

    We review our present knowledge on the intrinsic organization of the neocortex based on studies carried out with the Golgi method in several mammalian species. An outline is presented on certain general aspects of the termination of specific afferent fibers in layer IV in insectivora, rodents, carnivora and primates. The principal components of the cerebral cortex have been classified in two broad types: pyramidal cells, which account for nearly 70% of the total population, and intrinsic neur...

  2. Bone Morphogenetic Protein-7 Ameliorates Cerebral Ischemia and Reperfusion Injury via Inhibiting Oxidative Stress and Neuronal Apoptosis

    Directory of Open Access Journals (Sweden)

    Haitao Pei

    2013-11-01

    Full Text Available Previous studies have indicated that bone morphogenetic protein-7 (BMP-7 is neuroprotective against cerebral ischemia/reperfusion (IR injury. The present study was undertaken to determine the molecular mechanisms involved in this effect. Adult male Wistar rats were subjected to 2 h of transient middle cerebral artery occlusion (MCAO, followed by 24 h of reperfusion. BMP-7 (10−4 g/kg or vehicle was infused into rats at the onset of reperfusion via the tail vein. Neurological deficits, infarct volume, histopathological changes, oxidative stress-related biochemical parameters, neuronal apoptosis, and apoptosis-related proteins were assessed. BMP-7 significantly improved neurological and histological deficits, reduced the infarct volume, and decreased apoptotic cells after cerebral ischemia. BMP-7 also markedly enhanced the activities of antioxidant enzymes superoxide dismutase (SOD and glutathione peroxidase (GSH-PX, and reduced the level of malondialdehyde (MDA in IR rats. In addition, Western blot analysis indicated that BMP-7 prevented cytochrome c release, inhibited activation of caspase-3, caspase-9 and caspase-8. Our data suggested that BMP-7 has protective effects against cerebral IR injury in rats, and the neuroprotective effects may be attributed to attenuating oxidative stress and inhibiting neuronal apoptosis.

  3. PiB fails to map amyloid deposits in cerebral cortex of aged dogs with Canine Cognitive Dysfunction

    DEFF Research Database (Denmark)

    Fast, Rikke; Rodell, Anders; Gjedde, Albert;

    2013-01-01

    to the understanding of AD. However, the sensitivity of the biomarker Pittsburgh Compound B (PiB) to the presence of Aβ in humans and in other mammalian species is in doubt. To test the sensitivity and assess the distribution of Aβ in dog brain, we mapped the brains of dogs with signs of CCD (n = 16) and a control......]PiB in the cerebellum, compared to the cerebral cortex. Retention in the cerebellum is at variance with evidence from brains of humans with AD. To confirm the lack of sensitivity, we stained two dog brains with the immunohistochemical marker 6E10, which is sensitive to the presence of both Aβ and Aβ precursor protein......Dogs with Canine Cognitive Dysfunction (CCD) accumulate amyloid beta (Aβ) in the brain. As the cognitive decline and neuropathology of these old dogs share features with Alzheimer's disease (AD), the relation between Aβ and cognitive decline in animal models of cognitive decline is of interest...

  4. Astrocytic adaptation during cerebral angiogenesis follows the new vessel formation induced through chronic hypoxia in adult mouse cortex

    Science.gov (United States)

    Masamoto, Kazuto; Kanno, Iwao

    2014-03-01

    We examined longitudinal changes of the neuro-glia-vascular unit during cerebral angiogenesis induced through chronic hypoxia in the adult mouse cortex. Tie2-GFP mice in which the vascular endothelial cells expressed green fluorescent proteins (GFP) were exposed to chronic hypoxia, while the spatiotemporal developments of the cortical capillary sprouts and the neighboring astrocytic remodeling were characterized with repeated two-photon microscopy. The capillary sprouts appeared at early phases of the hypoxia adaptation (1-2 weeks), while the morphological changes of the astrocytic soma and processes were not detected in this phase. In the later phases of the hypoxia adaptation (> 2 weeks), the capillary sprouts created a new connection with existing capillaries, and its neighboring astrocytes extended their processes to the newly-formed vessels. The findings show that morphological adaptation of the astrocytes follow the capillary development during the hypoxia adaptation, which indicate that the newly-formed vessels provoke cellular interactions with the neighboring astrocytes to strengthen the functional blood-brain barrier.

  5. A nuclear localized protein ZCCHC9 is expressed in cerebral cortex and suppresses the MAPK signal pathway

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The CCHC-type zinc finger motif has numerous biological activities (such as DNA binding and RNA binding) and can also mediate protein-protein interaction. This article gives a primary report about the human ZCCHC9 gene. Protein ZCCHC9 contains four CCHC motifs and is highly conserved in humans, mice, and rats. The whole cDNA sequence of the ZCCHC9 gene has been amplified by PCR and a number of plasmids have been constructed for further study. The results show that ZCCHC9 is localized in the nucleus, and especially concentrated in the nucleolus. It is highly expressed in the brain and testicles of the mouse. This has been confirmed by real-time reverse transcription polymerase chain reaction (RT-PCR). In situ hybridization of the mouse brain indicates that ZCCHC9 is mainly expressed in the cerebral cortex. Reporter gene assay shows that ZCCHC9 suppresses the transcription activities of NF-kappa B and SRE,and may play roles in the Mitogen-Activated Protein Kinase (MAPK) signaling transduction pathway.

  6. Protocol to isolate a large amount of functional oligodendrocyte precursor cells from the cerebral cortex of adult mice and humans.

    Directory of Open Access Journals (Sweden)

    Eva María Medina-Rodríguez

    Full Text Available During development, oligodendrocytes are generated from oligodendrocyte precursor cells (OPCs, a cell type that is a significant proportion of the total cells (3-8% in the adult central nervous system (CNS of both rodents and humans. Adult OPCs are responsible for the spontaneous remyelination that occurs in demyelinating diseases like Multiple Sclerosis (MS and they constitute an interesting source of cells for regenerative therapy in such conditions. However, there is little data regarding the neurobiology of adult OPCs isolated from mice since an efficient method to isolate them has yet to be established. We have designed a protocol to obtain viable adult OPCs from the cerebral cortex of different mouse strains and we have compared its efficiency with other well-known methods. In addition, we show that this protocol is also useful to isolate functional OPCs from human brain biopsies. Using this method we can isolate primary cortical OPCs in sufficient quantities so as to be able to study their survival, maturation and function, and to facilitate an evaluation of their utility in myelin repair.

  7. Brain banks as key part of biochemical and molecular studies on cerebral cortex involvement in Parkinson's disease.

    Science.gov (United States)

    Ravid, Rivka; Ferrer, Isidro

    2012-04-01

    Exciting developments in basic and clinical neuroscience and recent progress in the field of Parkinson's disease (PD) are partly a result of the availability of human specimens obtained through brain banks. These banks have optimized the methodological, managerial and organizational procedures; standard operating procedures; and ethical, legal and social issues, including the code of conduct for 21st Century brain banking and novel protocols. The present minireview focuses on current brain banking organization and management, as well as the likely future direction of the brain banking field. We emphasize the potentials and pitfalls when using high-quality specimens of the human central nervous system for advancing PD research. PD is a generalized disease in which α-synuclein is not a unique component but, instead, is only one of the players accounting for the complex impairment of biochemical/molecular processes involved in metabolic pathways. This is particularly important in the cerebral cortex, where altered cognition has a complex neurochemical substrate. Mitochondria and energy metabolism impairment, abnormal RNA, microRNA, protein synthesis, post-translational protein modifications and alterations in the lipid composition of membranes and lipid rafts are part of these complementary factors. We have to be alert to the possible pitfalls of each specimen and its suitability for a particular study. Not all samples qualify for the study of DNA, RNA, proteins, post-translational modifications, lipids and metabolomes, although the use of carefully selected samples and appropriate methods minimizes pitfalls and errors and guarantees high-quality reserach.

  8. Automated identification of neurons and their locations

    CERN Document Server

    Inglis, Andrew; Roe, Dan L; Stanley, H E; Rosene, Douglas L; Urbanc, Brigita

    2007-01-01

    Individual locations of many neuronal cell bodies (>10^4) are needed to enable statistically significant measurements of spatial organization within the brain such as nearest-neighbor and microcolumnarity measurements. In this paper, we introduce an Automated Neuron Recognition Algorithm (ANRA) which obtains the (x,y) location of individual neurons within digitized images of Nissl-stained, 30 micron thick, frozen sections of the cerebral cortex of the Rhesus monkey. Identification of neurons within such Nissl-stained sections is inherently difficult due to the variability in neuron staining, the overlap of neurons, the presence of partial or damaged neurons at tissue surfaces, and the presence of non-neuron objects, such as glial cells, blood vessels, and random artifacts. To overcome these challenges and identify neurons, ANRA applies a combination of image segmentation and machine learning. The steps involve active contour segmentation to find outlines of potential neuron cell bodies followed by artificial ...

  9. Characterizing spatial tuning functions of neurons in the auditory cortex of young and aged monkeys: A new perspective on old data.

    OpenAIRE

    James Engle; Gregg H Recanzone

    2013-01-01

    Age-related hearing deficits are a leading cause of disability among the aged. While some forms of hearing deficits are peripheral in origin, others are centrally mediated. One such deficit is the ability to localize sounds, a critical component for segregating different acoustic objects and events, which is dependent on the auditory cortex. Recent evidence indicates that in aged animals the normal sharpening of spatial tuning between neurons in primary auditory cortex to the caudal latera...

  10. Controle neuronal e manifestações digestórias na paralisia cerebral Digestive tract neural control and gastrointestinal disorders in cerebral palsy

    OpenAIRE

    Liubiana A. Araújo; Silva, Luciana R; Fabiana A.A. Mendes

    2012-01-01

    OBJETIVOS: Abordar as peculiaridades do controle neuronal digestório e descrever as principais manifestações digestórias na paralisia cerebral, atentando-se à importância do diagnóstico precoce para intervenção interdisciplinar eficaz. FONTES DOS DADOS: Revisão sistemática de 1997 a 2012 das bases de dados MEDLINE, LILACS, SciELO e Cochrane Library. Incluem-se 70 artigos, como revisões relevantes, estudos observacionais, ensaios clínicos e estudos de prevalência. Excluíram-se pesquisas qualit...

  11. Maximization of learning speed in the motor cortex due to neuronal redundancy.

    Directory of Open Access Journals (Sweden)

    Ken Takiyama

    2012-01-01

    Full Text Available Many redundancies play functional roles in motor control and motor learning. For example, kinematic and muscle redundancies contribute to stabilizing posture and impedance control, respectively. Another redundancy is the number of neurons themselves; there are overwhelmingly more neurons than muscles, and many combinations of neural activation can generate identical muscle activity. The functional roles of this neuronal redundancy remains unknown. Analysis of a redundant neural network model makes it possible to investigate these functional roles while varying the number of model neurons and holding constant the number of output units. Our analysis reveals that learning speed reaches its maximum value if and only if the model includes sufficient neuronal redundancy. This analytical result does not depend on whether the distribution of the preferred direction is uniform or a skewed bimodal, both of which have been reported in neurophysiological studies. Neuronal redundancy maximizes learning speed, even if the neural network model includes recurrent connections, a nonlinear activation function, or nonlinear muscle units. Furthermore, our results do not rely on the shape of the generalization function. The results of this study suggest that one of the functional roles of neuronal redundancy is to maximize learning speed.

  12. Entry and distribution of microglial cells in human embryonic and fetal cerebral cortex.

    Science.gov (United States)

    Monier, Anne; Adle-Biassette, Homa; Delezoide, Anne-Lise; Evrard, Philippe; Gressens, Pierre; Verney, Catherine

    2007-05-01

    Microglial cells penetrate into and scatter throughout the human cortical grey and white matter according to a specific spatiotemporal pattern during the first 2 trimesters of gestation. Routes of entry were quantitatively and qualitatively different from those identified in the diencephalon. Starting at 4.5 gestational weeks, amoeboid microglial cells, characterized by different antibodies as Iba1, CD68, CD45, and MHC-II, entered the cerebral wall from the ventricular lumen and the leptomeninges. Migration was mainly radial and tangential toward the immature white matter, subplate layer, and cortical plate, whereas pial cells populated the prospective layer I. The intraparenchymal vascular route of entry was detectable only from 12 gestational weeks. Interestingly, microglial cells accumulated in restricted laminar bands particularly at 19 to 24 gestational weeks among the corona radiata fibers rostrally, extending caudally in the immature white matter to reach the visual radiations. This accumulation of proliferating MIB1-positive microglia (as shown by MIB1-Iba1 double immunolabeling) was located at the site of white matter injury in premature neonates. The spatiotemporal organization of microglia in the immature white and grey matter suggests that these cells may play active roles in developmental processes and in injury to the developing brain. PMID:17483694

  13. Recombinant human erythropoietin increases survival and reduces neuronal apoptosis in a murine model of cerebral malaria

    Directory of Open Access Journals (Sweden)

    Hempel Casper

    2008-01-01

    Full Text Available Abstract Background Cerebral malaria (CM is an acute encephalopathy with increased pro-inflammatory cytokines, sequestration of parasitized erythrocytes and localized ischaemia. In children CM induces cognitive impairment in about 10% of the survivors. Erythropoietin (Epo has – besides of its well known haematopoietic properties – significant anti-inflammatory, antioxidant and anti-apoptotic effects in various brain disorders. The neurobiological responses to exogenously injected Epo during murine CM were examined. Methods Female C57BL/6j mice (4–6 weeks, infected with Plasmodium berghei ANKA, were treated with recombinant human Epo (rhEpo; 50–5000 U/kg/OD, i.p. at different time points. The effect on survival was measured. Brain pathology was investigated by TUNEL (Terminal deoxynucleotidyl transferase (TdT-mediated deoxyuridine triphosphate (dUTP-digoxigenin nick end labelling, as a marker of apoptosis. Gene expression in brain tissue was measured by real time PCR. Results Treatment with rhEpo increased survival in mice with CM in a dose- and time-dependent manner and reduced apoptotic cell death of neurons as well as the expression of pro-inflammatory cytokines in the brain. This neuroprotective effect appeared to be independent of the haematopoietic effect. Conclusion These results and its excellent safety profile in humans makes rhEpo a potential candidate for adjunct treatment of CM.

  14. Expression of glutamine transporter isoforms in cerebral cortex of rats with chronic hepatic encephalopathy

    DEFF Research Database (Denmark)

    Leke, Renata; Escobar, Thayssa D.C.; Rama Rao, Kakulavarapu V.;

    2015-01-01

    Hepatic encephalopathy (HE) is a neuropsychiatric disorder that occurs due to acute and chronic liver diseases, the hallmark of which is the increased levels of ammonia and subsequent alterations in glutamine synthesis, i.e. conditions associated with the pathophysiology of HE. Under physiological...... conditions, glutamine is fundamental for replenishment of the neurotransmitter pools of glutamate and GABA. The different isoforms of glutamine transporters play an important role in the transfer of this amino acid between astrocytes and neurons. A disturbance in the GABA biosynthetic pathways has been...... described in bile duct ligated (BDL) rats, a well characterized model of chronic HE. Considering that glutamine is important for GABA biosynthesis, altered glutamine transport and the subsequent glutamate/GABA–glutamine cycle efficacy might influence these pathways. Given this potential outcome, the aim...

  15. Brazilein inhibits neuronal inflammation induced by cerebral ischemia and oxygen-glucose deprivation through targeting NOD2 expression.

    Science.gov (United States)

    Yan, Xiao-Jin; Chai, Yu-Shuang; Yuan, Zhi-Yi; Wang, Xin-Pei; Jiang, Jing-Fei; Lei, Fan; Xing, Dong-Ming; DU, Li-Jun

    2016-05-01

    Brazilein is reported to have immunosuppressive effect on cardiovascular and cerebral-vascular diseases. The essential roles of innate immunity in cerebral ischemia are increasingly identified, but no studies concerning the influence of brazilein on the innate immunity receptors have been reported. The present study was designed to investigate the regulation of NOD2 (Nucleotide-binding oligomerization domain-containing protein 2) by brazilein for its protection of neuron in cerebral ischemia in vivo and oxygen-glucose deprivation in vitro. The results showed that brazilein could reverse the elevated expression of NOD2 and TNFα (tumor necrosis factor alpha) elicited by cerebral ischemia and reperfusion. This reduction could also be detected in normal mice and C17.2 cells, indicating that this suppressive effect of brazilein was correlated with NOD2. The results from GFP reporter plasmid assay suggested brazilein inhibited NOD2 gene transcription. In conclusion, brazilein could attenuate NOD2 and TNFα expression in cerebral ischemia and NOD2 may be one possible target of brazilein for its immune suppressive effect in neuro-inflammation. PMID:27478098

  16. Arctigenin reduces neuronal responses in the somatosensory cortex via the inhibition of non-NMDA glutamate receptors.

    Science.gov (United States)

    Borbély, Sándor; Jócsák, Gergely; Moldován, Kinga; Sedlák, Éva; Preininger, Éva; Boldizsár, Imre; Tóth, Attila; Atlason, Palmi T; Molnár, Elek; Világi, Ildikó

    2016-07-01

    Lignans are biologically active phenolic compounds related to lignin, produced in different plants. Arctigenin, a dibenzylbutyrolactone-type lignan, has been used as a neuroprotective agent for the treatment of encephalitis. Previous studies of cultured rat cerebral cortical neurones raised the possibility that arctigenin inhibits kainate-induced excitotoxicity. The aims of the present study were: 1) to analyse the effect of arctigenin on normal synaptic activity in ex vivo brain slices, 2) to determine its receptor binding properties and test the effect of arctigenin on AMPA/kainate receptor activation and 3) to establish its effects on neuronal activity in vivo. Arctigenin inhibited glutamatergic transmission and reduced the evoked field responses. The inhibitory effect of arctigenin on the evoked field responses proved to be substantially dose dependent. Our results indicate that arctigenin exerts its effects under physiological conditions and not only on hyper-excited neurons. Furthermore, arctigenin can cross the blood-brain barrier and in the brain it interacts with kainate sensitive ionotropic glutamate receptors. These results indicate that arctigenin is a potentially useful new pharmacological tool for the inhibition of glutamate-evoked responses in the central nervous system in vivo. PMID:26972612

  17. Arctigenin reduces neuronal responses in the somatosensory cortex via the inhibition of non-NMDA glutamate receptors.

    Science.gov (United States)

    Borbély, Sándor; Jócsák, Gergely; Moldován, Kinga; Sedlák, Éva; Preininger, Éva; Boldizsár, Imre; Tóth, Attila; Atlason, Palmi T; Molnár, Elek; Világi, Ildikó

    2016-07-01

    Lignans are biologically active phenolic compounds related to lignin, produced in different plants. Arctigenin, a dibenzylbutyrolactone-type lignan, has been used as a neuroprotective agent for the treatment of encephalitis. Previous studies of cultured rat cerebral cortical neurones raised the possibility that arctigenin inhibits kainate-induced excitotoxicity. The aims of the present study were: 1) to analyse the effect of arctigenin on normal synaptic activity in ex vivo brain slices, 2) to determine its receptor binding properties and test the effect of arctigenin on AMPA/kainate receptor activation and 3) to establish its effects on neuronal activity in vivo. Arctigenin inhibited glutamatergic transmission and reduced the evoked field responses. The inhibitory effect of arctigenin on the evoked field responses proved to be substantially dose dependent. Our results indicate that arctigenin exerts its effects under physiological conditions and not only on hyper-excited neurons. Furthermore, arctigenin can cross the blood-brain barrier and in the brain it interacts with kainate sensitive ionotropic glutamate receptors. These results indicate that arctigenin is a potentially useful new pharmacological tool for the inhibition of glutamate-evoked responses in the central nervous system in vivo.

  18. Electrophysiology Alterations in Primary Visual Cortex Neurons of Retinal Degeneration (S334ter-line-3) Rats.

    Science.gov (United States)

    Chen, Ke; Wang, Yi; Liang, Xiaohua; Zhang, Yihuai; Ng, Tsz Kin; Chan, Leanne Lai Hang

    2016-01-01

    The dynamic nature of the brain is critical for the success of treatments aimed at restoring vision at the retinal level. The success of these treatments relies highly on the functionality of the surviving neurons along the entire visual pathway. Electrophysiological properties at the retina level have been investigated during the progression of retinal degeneration; however, little is known about the changes in electrophysiological properties that occur in the primary visual cortex (V1) during the course of retinal degeneration. By conducting extracellular recording, we examined the electrophysiological properties of V1 in S334ter-line-3 rats (a transgenic model of retinal degeneration developed to express a rhodopsin mutation similar to that found in human retinitis pigmentosa patients). We measured the orientation tuning, spatial and temporal frequency tunings and the receptive field (RF) size for 127 V1 neurons from 11 S334ter-3 rats and 10 Long-Evans (LE) rats. V1 neurons in the S334ter-3 rats showed weaker orientation selectivity, lower optimal spatial and temporal frequency values and a smaller receptive field size compared to the LE rats. These results suggest that the visual cognitive ability significantly changes during retinal degeneration. PMID:27225415

  19. Changes of MCT2 expression in cerebral cortex after formalin-induced rat pain model%MCT2在福尔马林致痛模型大鼠大脑皮质中的表达变化

    Institute of Scientific and Technical Information of China (English)

    宋开琴; 康承巧; 孙善全; 黄娟; 徐进; 李文娟; 蒋锦

    2014-01-01

    目的:观察疼痛应激时,大脑第一躯体感觉皮质后肢区(primary somatosensory cortex hindlimb region,S1HL)神经元单羧酸转运蛋2(monocarboxylate transporters 2,MCT2)的表达变化,以探讨MCT2参与疼痛调制的机制。方法应用免疫组织化学(IHC)、Western blot和计算机图像分析法检测福尔马林致痛大鼠模型大脑S1HL内MCT2的表达变化。结果与正常组相比,模型鼠S1HL内MCT2阳性神经元的数量及IOD在1 h时增加,3 d时达高峰,到7 d时有所下降,但仍然高于正常水平(P<0.05)。Western blot结果显示,MCT2蛋白表达变化与MCT2阳性神经元的数量和IOD变化趋势一致。结论在疼痛应激状态下,大脑S1HL神经元MCT2的表达增强,提示MCT2参与了疼痛的产生、传递和调制过程。%Objective To investigate the changeofmonocarboxylate transporters 2( MCT2) expression in cerebral cortex primary somatosensory cortex hindlimb region(S1HL)under the condition of pain stimulation, so as to explore the involvement of MCT2 in the pain adjustment mechanism in a rat pain model. Methods Immunohistochemical staining(IHC), Western blot and Computing- image analysis system were used to detect the changes of MCT2 expression in the cerebral cortex S1HL of the formalin-induced rat pain model. Results Compared with the control group, the number and IOD of MCT2-positive neurons in the cerebral cortex S1HL of formalin-treated rats began to increase at 1h,reaching the highest level on 3d and declined on 7d ,but still higher than those in the control group (P<0.05).The Western blot showed that the alteration tendency of MCT2 expression was consistent with those of the number and IOD of MCT2-positive neurons. Conclusion Our results indicated that MCT2 is up-regulated under the condition of pain stimulation, which might be involved in the formalin-induced pain and behavior regulation.

  20. Cellular scaling rules for the brain of Artiodactyla include a highly folded cortex with few neurons

    OpenAIRE

    Rodrigo eSiqueira Kazu; Jose eMaldonado; Bruno eMota; Paul eManger; Suzana eHerculano-Houzel

    2014-01-01

    Quantitative analysis of the cellular composition of rodent, primate, insectivore, and afrotherian brains has shown that non-neuronal scaling rules are similar across these mammalian orders that diverged about 95 million years ago, and therefore appear to be conserved in evolution, while neuronal scaling rules appear to be free to vary in a clade-specific manner. Here we analyze the cellular scaling rules that apply to the brain of artiodactyls, a group within the order Cetartiodactyla, belie...

  1. Kainate-enhanced release of D-(3H)aspartate from cerebral cortex and striatum: reversal by baclofen and pentobarbital

    Energy Technology Data Exchange (ETDEWEB)

    Potashner, S.J.; Gerard, D.

    1983-06-01

    A study was made of the actions of the excitant neurotoxin, kainic acid, on the uptake and the release of D-(2,3-3H)aspartate (D-ASP) in slices of guinea pig cerebral neocortex and striatum. The slices took up D-ASP, reaching concentrations of the amino acid in the tissue which were 14-23 times that in the medium. Subsequently, electrical stimulation of the slices evoked a Ca2+-dependent release of a portion of the D-ASP. Kainic acid (10(-5)-10(-3) M) produced a dose-dependent inhibition of D-ASP uptake. The electrically evoked release of D-ASP was increased 1.6-2.0 fold by 10(-5) and 10(-4)M kainic acid. The kainate-enlarged release was Ca2+-dependent. Dihydrokainic acid, an analogue of kainic acid with little excitatory or toxic action, did not increase D-ASP release but depressed D-ASP uptake. Attempts were made to block the action of kainic acid with baclofen and pentobarbital, compounds which depress the electrically evoked release of L-glutamate (L-GLU) and L-aspartate (L-ASP). Baclofen (4 X 10(-6)M), an antispastic drug, and pentobarbital (10(-4)M), an anesthetic agent, each inhibited the electrically evoked release of D-ASP and prevented the enhancement of the release above control levels usually produced by 10(-4)M kainic acid. It is proposed that 10(-5) and 10(-4)M kainic acid may enhance the synaptic release of L-GLU and L-ASP from neurons which use these amino acids as transmitters. This action is prevented by baclofen and pentobarbital. In view of the possibility that cell death in Huntington's disease could involve excessive depolarization of striatal and other cells by glutamate, baclofen might be effective in delaying the loss of neurons associated with this condition.

  2. Patterns of Spontaneous Local Network Activity in Developing Cerebral Cortex: Relationship to Adult Cognitive Function.

    Directory of Open Access Journals (Sweden)

    Alejandro Peinado

    Full Text Available Detecting neurodevelopμental disorders of cognition at the earliest possible stages could assist in understanding them mechanistically and ultimately in treating them. Finding early physiological predictors that could be visualized with functional neuroimaging would represent an important advance in this regard. We hypothesized that one potential source of physiological predictors is the spontaneous local network activity prominent during specific periods in development. To test this we used calcium imaging in brain slices and analyzed variations in the frequency and intensity of this early activity in one area, the entorhinal cortex (EC, in order to correlate early activity with level of cognitive function later in life. We focused on EC because of its known role in different types of cognitive processes and because it is an area where spontaneous activity is prominent during early postnatal development in rodent models of cortical development. Using rat strains (Long-Evans, Wistar, Sprague-Dawley and Brattleboro known to differ in cognitive performance in adulthood we asked whether neonatal animals exhibit corresponding strain-related differences in EC spontaneous activity. Our results show significant differences in this activity between strains: compared to a high cognitive-performing strain, we consistently found an increase in frequency and decrease in intensity in neonates from three lower performing strains. Activity was most different in one strain considered a model of schizophrenia-like psychopathology. While we cannot necessarily infer a causal relationship between early activity and adult cognition our findings suggest that the pattern of spontaneous activity in development could be an early predictor of a developmental trajectory advancing toward sub-optimal cognitive performance in adulthood. Our results further suggest that the strength of dopaminergic signaling, by setting the balance between excitation and inhibition, is a

  3. Probabilistic map of critical functional regions of the human cerebral cortex: Broca's area revisited.

    Science.gov (United States)

    Tate, Matthew C; Herbet, Guillaume; Moritz-Gasser, Sylvie; Tate, Joseph E; Duffau, Hugues

    2014-10-01

    The organization of basic functions of the human brain, particularly in the right hemisphere, remains poorly understood. Recent advances in functional neuroimaging have improved our understanding of cortical organization but do not allow for direct interrogation or determination of essential (versus participatory) cortical regions. Direct cortical stimulation represents a unique opportunity to provide novel insights into the functional distribution of critical epicentres. Direct cortical stimulation (bipolar, 60 Hz, 1-ms pulse) was performed in 165 consecutive patients undergoing awake mapping for resection of low-grade gliomas. Tasks included motor, sensory, counting, and picture naming. Stimulation sites eliciting positive (sensory/motor) or negative (speech arrest, dysarthria, anomia, phonological and semantic paraphasias) findings were recorded and mapped onto a standard Montreal Neurological Institute brain atlas. Montreal Neurological Institute-space functional data were subjected to cluster analysis algorithms (K-means, partition around medioids, hierarchical Ward) to elucidate crucial network epicentres. Sensorimotor function was observed in the pre/post-central gyri as expected. Articulation epicentres were also found within the pre/post-central gyri. However, speech arrest localized to ventral premotor cortex, not the classical Broca's area. Anomia/paraphasia data demonstrated foci not only within classical Wernicke's area but also within the middle and inferior frontal gyri. We report the first bilateral probabilistic map for crucial cortical epicentres of human brain functions in the right and left hemispheres, including sensory, motor, and language (speech, articulation, phonology and semantics). These data challenge classical theories of brain organization (e.g. Broca's area as speech output region) and provide a distributed framework for future studies of neural networks.

  4. Morphology and kainate-receptor immunoreactivity of identified neurons within the entorhinal cortex projecting to superior temporal sulcus in the cynomolgus monkey

    Science.gov (United States)

    Good, P. F.; Morrison, J. H.; Bloom, F. E. (Principal Investigator)

    1995-01-01

    Projections of the entorhinal cortex to the hippocampus are well known from the classical studies of Cajal (Ramon y Cajal, 1904) and Lorente de No (1933). Projections from the entorhinal cortex to neocortical areas are less well understood. Such connectivity is likely to underlie the consolidation of long-term declarative memory in neocortical sites. In the present study, a projection arising in layer V of the entorhinal cortex and terminating in a polymodal association area of the superior temporal gyrus has been identified with the use of retrograde tracing. The dendritic arbors of neurons giving rise to this projection were further investigated by cell filling and confocal microscopy with computer reconstruction. This analysis demonstrated that the dendritic arbor of identified projection neurons was largely confined to layer V, with the exception of a solitary, simple apical dendrite occasionally ascending to superficial laminae but often confined to the lamina dissecans (layer IV). Finally, immunoreactivity for glutamate-receptor subunit proteins GluR 5/6/7 of the dendritic arbor of identified entorhinal projection neurons was examined. The solitary apical dendrite of identified entorhinal projection neurons was prominently immunolabeled for GluR 5/6/7, as was the dendritic arbor of basilar dendrites of these neurons. The restriction of the large bulk of the dendritic arbor of identified entorhinal projection neurons to layer V implies that these neurons are likely to be heavily influenced by hippocampal output arriving in the deep layers of the entorhinal cortex. Immunoreactivity for GluR 5/6/7 throughout the dendritic arbor of such neurons indicates that this class of glutamate receptor is in a position to play a prominent role in mediating excitatory neurotransmission within hippocampal-entorhinal circuits.

  5. EFFECT OF ELECTROACUPUNCTURE ON DISCHARGES OF PAINREACTION NEURONS IN CAUDATE NUCLEUS AND PARAFACICULAR NUCLEUS IN RATS WITH CEREBRAL HEMORRHAGE

    Institute of Scientific and Technical Information of China (English)

    DONG Gui-rong; BAI Yan; JIN Chun-yu; DONG Hong-sheng; LI Li-qiu

    2005-01-01

    Objective:To study the bidirectional adjustment effect of electroacupuncture (EA) on the electrical activities of neurons in caudate nucleus (CN) and parafascicular nucleus (PFN) in rats with acute cerebral hemorrhage (ACH). Methods: ① 32 male Wistar rats were evenly randomized into normal, EA+normal, model and model+EA groups for observing the effect of EA on pain reaction; ② another 40 male Wistar rats were equally randomized into control, saline, model and EA groups for comparing the effects of EA on discharges of pain-reaction neurons in CN and PFN. ACH model was established by intracerebral injection of the rat's own arterial blood sample (30μL) into CN and PFN. Pain reaction was tested by using tail-flicking (TF) reflex induced by radiation-heat irradiation. Extra-cellular discharges of neurons of CN and PFN were recorded by using glass micropipettes. EA (1 V, 15 Hz and duration of 10 min) was applied to"Baihui"(百会 GV 20) and "Taiyang"(太阳 EX-HN 5). Frequency of discharges of CN and PFN neurons was calculated before and after intracerebral injection of blood sample, heat nociceptive stimulation and EA respectively. Results: Compared with control group and pre-EA in the same group, TF latency (TFL) values of normal rats increased significantly; compared with pre-injection of blood, TFL of model group also increased pronouncedly (P<0.01). In comparison with model group, TFL values of EA group decreased significantly (P<0.01), indicating that EA of GV 20 and EX-HN 5 could suppress ACH induced increase of TFL. In ACH rats, the latency of pain-excitement response of discharges of CN and PFN neurons increased significantly, while the net increase values of pain-excitement response decreased significantly in model group (P<0.05~0.01), the duration of pain-inhibitory response and the net decrease values of discharges of CN and PFN neurons increased clearly. Comparison between model and EA groups showed that the latency values of the pain

  6. Identity of neocortical layer 4 neurons is specified through correct positioning into the cortex.

    Science.gov (United States)

    Oishi, Koji; Nakagawa, Nao; Tachikawa, Kashiko; Sasaki, Shinji; Aramaki, Michihiko; Hirano, Shinji; Yamamoto, Nobuhiko; Yoshimura, Yumiko; Nakajima, Kazunori

    2016-02-12

    Many cell-intrinsic mechanisms have been shown to regulate neuronal subtype specification in the mammalian neocortex. However, how much cell environment is crucial for subtype determination still remained unclear. Here, we show that knockdown of Protocadherin20 (Pcdh20), which is expressed in post-migratory neurons of layer 4 (L4) lineage, caused the cells to localize in L2/3. The ectopically positioned "future L4 neurons" lost their L4 characteristics but acquired L2/3 characteristics. Knockdown of a cytoskeletal protein in the future L4 neurons, which caused random disruption of positioning, also showed that those accidentally located in L4 acquired the L4 characteristics. Moreover, restoration of positioning of the Pcdh20-knockdown neurons into L4 rescued the specification failure. We further suggest that the thalamocortical axons provide a positional cue to specify L4 identity. These results suggest that the L4 identity is not completely determined at the time of birth but ensured by the surrounding environment after appropriate positioning.

  7. Structural changes in pyramidal cell dendrites and synapses in the unaffected side of the sensorimotor cortex following transcranial magnetic stimulation and rehabilitation training in a rat model of focal cerebral infarct

    Institute of Scientific and Technical Information of China (English)

    Chuanyu Liu; Surong Zhou; Xuwen Sun; Zhuli Liu; Hongliang Wu; Yuanwu Mei

    2011-01-01

    Very little is known about the effects of transcranial magnetic stimulation and rehabilitation training on pyramidal cell dendrites and synapses of the contralateral, unaffected sensorimotor cortex in a rat model of focal cerebral infarct. The present study was designed to explore the mechanisms underlying improved motor function via transcranial magnetic stimulation and rehabilitation training following cerebral infarction. Results showed that rehabilitation training or transcranial magnetic stimulation alone reduced neurological impairment in rats following cerebral infarction, as well as significantly increased synaptic curvatures and post-synaptic density in the non-injured cerebral hemisphere sensorimotor cortex and narrowed the synapse cleft width. In addition, the percentage of perforated synapses increased. The combination of transcranial magnetic stimulation and rehabilitation resulted in significantly increased total dendritic length, dendritic branching points, and dendritic density in layer V pyramidal cells of the non-injured cerebral hemisphere motor cortex.These results demonstrated that transcranial magnetic stimulation and rehabilitation training altered structural parameters of pyramidal cell dendrites and synapses in the non-injured cerebral hemisphere sensorimotor cortex, thereby improving the ability to compensate for neurological functions in rats following cerebral infarction.

  8. Attenuated Sensory Deprivation-induced Changes of Parvalbumin Neuron Density in the Barrel Cortex of FcγRllB-deficient Mice

    Directory of Open Access Journals (Sweden)

    Watanabe,Makiko

    2012-04-01

    Full Text Available Recent studies have demonstrated the important role of immune molecules in the development of neuronal circuitry and synaptic plasticity. We have detected the presence of FcγRllB protein in parvalbumin- containing inhibitory interneurons (PV neurons. In the present study, we examined the appearance of PV neurons in the barrel cortex and the effect of sensory deprivation in FcγRllB-deficient mice (FcγRllB-/- and wild-type mice. There was no substantial difference in the appearance of PV neurons in the developing barrel cortex between FcγRllB-/- and wild-type mice. Sensory deprivation from immediately after birth (P0 or P7 to P12-P14 induced an increase in PV neurons. In contrast, sensory deprivation from P7 or P14 to P28, but not from P21 to P28, decreased PV neurons in wild-type mice. However, sensory deprivation from P0 or P7 to P12-P14 did not increase PV neurons and sensory deprivation from P7 or P14 to P28 did not decrease or only modestly decreased PV neurons in FcγRllB-/- mice. The results indicate that expression of PV is regulated by sensory experience and the second and third postnatal weeks are a sensitive period for sensory deprivation, and suggest that FcγRllB contributes to sensory experience-regulated expression of PV.

  9. Riluzole-Triggered GSH Synthesis via Activation of Glutamate Transporters to Antagonize Methylmercury-Induced Oxidative Stress in Rat Cerebral Cortex

    Directory of Open Access Journals (Sweden)

    Yu Deng

    2012-01-01

    Full Text Available Objective. This study was to evaluate the effect of riluzole on methylmercury- (MeHg- induced oxidative stress, through promotion of glutathione (GSH synthesis by activating of glutamate transporters (GluTs in rat cerebral cortex. Methods. Eighty rats were randomly assigned to four groups, control group, riluzole alone group, MeHg alone group, and riluzole + MeHg group. The neurotoxicity of MeHg was observed by measuring mercury (Hg absorption, pathological changes, and cell apoptosis of cortex. Oxidative stress was evaluated via determining reactive oxygen species (ROS, 8-hydroxy-2-deoxyguanosine (8-OHdG, malondialdehyde (MDAs, carbonyl, sulfydryl, and GSH in cortex. Glutamate (Glu transport was studied by measuring Glu, glutamine (Gln, mRNA, and protein of glutamate/aspartate transporter (GLAST and glutamate transporter-1 (GLT-1. Result. (1 MeHg induced Hg accumulation, pathological injury, and apoptosis of cortex; (2 MeHg increased ROS, 8-OHdG, MDA, and carbonyl, and inhibited sulfydryl and GSH; (3 MeHg elevated Glu, decreased Gln, and downregulated GLAST and GLT-1 mRNA expression and protein levels; (4 riluzole antagonized MeHg-induced downregulation of GLAST and GLT-1 function and expression, GSH depletion, oxidative stress, pathological injury, and apoptosis obviously. Conclusion. Data indicate that MeHg administration induced oxidative stress in cortex and that riluzole could antagonize this situation through elevation of GSH synthesis by activating of GluTs.

  10. Neuroprotective potential of Bacopa monnieri and Bacoside A against dopamine receptor dysfunction in the cerebral cortex of neonatal hypoglycaemic rats.

    Science.gov (United States)

    Thomas, Roshni Baby; Joy, Shilpa; Ajayan, M S; Paulose, C S

    2013-11-01

    Neonatal hypoglycaemia initiates a series of events leading to neuronal death, even if glucose and glycogen stores return to normal. Disturbances in the cortical dopaminergic function affect memory and cognition. We recommend Bacopa monnieri extract or Bacoside A to treat neonatal hypoglycaemia. We investigated the alterations in dopaminergic functions by studying the Dopamine D1 and D2 receptor subtypes. Receptor-binding studies revealed a significant decrease (p Bacoside A ameliorated the dopaminergic and cAMP imbalance as effectively as the glucose therapy. The upregulated Bax expression in the present study indicates the high cell death in hypoglycaemic neonatal rats. Enzyme assay of SOD confirmed cortical cell death due to free radical accumulation. The gene expression of SOD in the cortex was significantly downregulated (p < 0.001). Bacopa treatment showed a significant reversal in the altered gene expression parameters (p < 0.001) of Bax and SOD. Our results suggest that in the rat experimental model of neonatal hypoglycaemia, Bacopa extract improved alterations in D1, D2 receptor expression, cAMP signalling and cell death resulting from oxidative stress. This is an important area of study given the significant motor and cognitive impairment that may arise from neonatal hypoglycaemia if proper treatment is not implemented.

  11. The Infralimbic Cortex Bidirectionally Modulates Mesolimbic Dopamine Neuron Activity via Distinct Neural Pathways

    OpenAIRE

    Patton, Mary H.; Bizup, Brandon T.; Grace, Anthony A.

    2013-01-01

    The ventral tegmental area (VTA) has been implicated in a number of psychiatric disorders, including schizophrenia, depression, and bipolar disorder. One major regulator of the mesolimbic dopaminergic system is the medial prefrontal cortex (mPFC), which makes direct and indirect connections to the hippocampus and amygdala, as well as directly to the VTA. The mPFC is comprised of two subregions: the infralimbic and prelimbic cortices (ilPFC and plPFC). However, the specific roles of these subr...

  12. Sleep loss alters synaptic and intrinsic neuronal properties in mouse prefrontal cortex

    OpenAIRE

    Winters, Bradley D.; Huang, Yanhua H.; Dong, Yan; Krueger, James M.

    2011-01-01

    Despite sleep-loss-induced cognitive deficits, little is known about the cellular adaptations that occur with sleep loss. We used brain slices obtained from mice that were sleep deprived for 8 h to examine the electrophysiological effects of sleep deprivation (SD). We employed a modified pedestal (flowerpot) over water method for SD that eliminated rapid eye movement sleep and greatly reduced non-rapid eye movement sleep. In layer V/VI pyramidal cells of the medial prefrontal cortex, miniatur...

  13. Plasma level of neuron specific enolase in patients with acute cerebral infarction: A case-control study

    Institute of Scientific and Technical Information of China (English)

    Guoping Tian; Yang Zhang; Weiping Cheng

    2009-01-01

    BACKGROUND: The plasma level of neuron specific enolase (NSE) can be used to diagnose and evaluate neuronal injury and predict early prognosis.OBJECTIVE: To observe the dynamic changes in plasma levels of NSE in patients with acute cerebral infarction, and to investigate its correlations with disease severity and prognosis.DESIGN, TIME AND SETTING: This non-randomized, concurrent case-control experiment was performed at the Department of Neurology, First Hospital Affiliated to Heilongjiang University of Traditional Chinese Medicine between May and July 2007.PARTICIPANTS: Eighteen patients with acute cerebral infarction, who received treatment at the Department of Neurology, First Hospital Affiliated to Heilongjiang University of Traditional Chinese Medicine between May and July 2007, were recruited into the patient group. An additional 10 healthy individuals, who received health examinations simultaneously, were included as controls.METHODS: Following admission (within 3 days) and at days 6, 12, and 30 subsequent to acute cerebral infarction attack, 3 mL venous blood was taken from each patient before the morning meal to determine the plasma level of NSE by enzyme-labeled immunosorbent assay. One-time blood extraction was performed in each healthy subject during the health examination for the same purpose as in patients. At 6 and 30 days following acute cerebral infarction attack, CT examination was performed for calculation of cerebral infarction volume according to the Tada formula. Following admission and at 30 days of disease invasion, all patients were scored by the National Institutes of Health Stroke Scale (NIHSS, 13 items).MAIN OUTCOME MEASURES: Comparison of NSE plasma level between acute cerebral infarction patients and healthy individuals; correlations of NSE plasma level in acute cerebral infarction patients with cerebral infarction volume, NIHSS score, and prognosis.RESULTS: Following admission and at days 6 and 12 of disease invasion, the plasma level

  14. “Subpial Fan Cell” — A Class of Calretinin Neuron in Layer 1 of Adult Monkey Prefrontal Cortex

    Science.gov (United States)

    Gabbott, Paul L. A.

    2016-01-01

    Layer 1 of the cortex contains populations of neurochemically distinct neurons and afferent fibers which markedly affect neural activity in the apical dendritic tufts of pyramidal cells. Understanding the causal mechanisms requires knowledge of the cellular architecture and synaptic organization of layer 1. This study has identified eight morphological classes of calretinin immunopositive (CRet+) neurons (including Cajal-Retzius cells) in layer 1 of the prefrontal cortex (PFC) in adult monkey (Macaca fasicularis), with a distinct class — termed “subpial fan (SPF) cell” — described in detail. SPF cells were rare horizontal unipolar CRet+ cells located directly beneath the pia with a single thick primary dendrite that branched into a characteristic fan-like dendritic tree tangential to the pial surface. Dendrites had spines, filamentous processes and thorny branchlets. SPF cells lay millimeters apart with intralaminar axons that ramified widely in upper layer 1. Such cells were GABA immunonegative (-) and occurred in areas beyond PFC. Interspersed amidst SPF cells displaying normal structural integrity were degenerating CRet+ neurons (including SPF cells) and clumps of lipofuscin-rich cellular debris. The number of degenerating SPF cells increased during adulthood. Ultrastructural analyses indicated SPF cell somata received asymmetric (A — presumed excitatory) and symmetric (S — presumed inhibitory) synaptic contacts. Proximal dendritic shafts received mainly S-type and distal shafts mostly A-type input. All dendritic thorns and most dendritic spines received both synapse types. The tangential areal density of SPF cell axonal varicosities varied radially from parent somata — with dense clusters in more distal zones. All boutons formed A-type contacts with CRet- structures. The main post-synaptic targets were dendritic shafts (67%; mostly spine-bearing) and dendritic spines (24%). SPF-SPF cell innervation was not observed. Morphometry of SPF cells

  15. ‘Subpial fan cell’ – a class of calretinin neuron in layer 1 of adult monkey prefrontal cortex.

    Directory of Open Access Journals (Sweden)

    Paul L A Gabbott

    2016-04-01

    Full Text Available Layer 1 of the cortex contains populations of neurochemically distinct neurons and afferent fibres which markedly affect neural activity in the apical dendritic tufts of pyramidal cells. Understanding the causal mechanisms requires knowledge of the cellular architecture and synaptic organisation of layer 1. This study has identified 8 morphological classes of calretinin immunopositive (CRet+ neurons (including Cajal-Retzius cells in layer 1 of the prefrontal cortex (PFC in adult monkey (Macaca fasicularis, with a distinct class - termed ‘subpial fan (SPF cell’ - described in detail.SPF cells were rare horizontal unipolar CRet+ cells located directly beneath the pia with a single thick primary dendrite that branched into a characteristic fan-like dendritic tree tangential to the pial surface. Dendrites had spines, filamentous processes and thorny branchlets. SPF cells lay millimetres apart with axons that ramified widely in upper layer 1. Such cells were GABA immunonegative (- and occurred in areas beyond PFC. Interspersed amidst SPF cells displaying normal structural integrity were degenerating CRet+ neurons (including SPF cells and clumps of lipofuscin-rich cellular debris. The number of degenerating SPF cells increased during adulthood. Ultrastructural analyses indicated SPF cell somata received asymmetric (A - presumed excitatory and symmetric (S - presumed inhibitory synaptic contacts. Proximal dendritic shafts received mainly S-type and distal shafts mostly A-type input. All dendritic thorns and most dendritic spines received both synapse types. The tangential areal density of SPF cell axonal varicosities varied radially from parent somata - with dense clusters in more distal zones. All boutons formed A-type contacts with CRet- structures. The main post-synaptic targets were dendritic shafts (67%; mostly spine-bearing and dendritic spines (24%. SPF-SPF cell innervation was not observed. Morphometry of SPF cells indicated a unique class

  16. Muscarinic receptor control of pyramidal neuron membrane potential in the medial prefrontal cortex (mPFC) in rats.

    Science.gov (United States)

    Kurowski, P; Gawlak, M; Szulczyk, P

    2015-09-10

    Damage to the cholinergic input to the prefrontal cortex has been implicated in neuropsychiatric disorders. Cholinergic endings release acetylcholine, which activates nicotinic and/or G-protein-coupled muscarinic receptors. Muscarinic receptors activate transduction systems, which control cellular effectors that regulate the membrane potential in medial prefrontal cortex (mPFC) neurons. The mechanisms responsible for the cholinergic-dependent depolarization of mPFC layer V pyramidal neurons in slices obtained from young rats were elucidated in this study. Glutamatergic and GABAergic transmission as well as tetrodotoxin (TTX)-sensitive Na(+) and voltage-dependent Ca(++) currents were eliminated. Cholinergic receptor stimulation by carbamoylcholine chloride (CCh; 100 μM) evoked depolarization (10.0 ± 1.3 mV), which was blocked by M1/M4 (pirenzepine dihydrochloride, 2 μM) and M1 (VU 0255035, 5 μM) muscarinic receptor antagonists and was not affected by a nicotinic receptor antagonist (mecamylamine hydrochloride, 10 μM). CCh-dependent depolarization was attenuated by extra- (20 μM) or intracellular (50 μM) application of an inhibitor of the βγ-subunit-dependent transduction system (gallein). It was also inhibited by intracellular application of a βγ-subunit-binding peptide (GRK2i, 10μM). mPFC pyramidal neurons express Nav1.9 channels. CCh-dependent depolarization was abolished in the presence of antibodies against Nav1.9 channels in the intracellular solution and augmented by the presence of ProTx-I toxin (100 nM) in the extracellular solution. CCh-induced depolarization was not affected by the following reagents: intracellular transduction system blockers, including U-73122 (10 μM), chelerythrine chloride (5 μM), SQ 22536 (100 μM) and H-89 (2 μM); channel blockers, including Ba(++) ions (200 μM), apamin (100 nM), flufenamic acid (200 μM), 2-APB (200 μM), SKF 96365 (50 μM), and ZD 7288 (50 μM); and a Na(+)/Ca(++) exchanger blocker, benzamil (20

  17. The effects of kinesio taping on potential in chronic low back pain patients anticipatory postural control and cerebral cortex.

    Science.gov (United States)

    Bae, Sea Hyun; Lee, Jeong Hun; Oh, Kyeong Ae; Kim, Kyung Yoon

    2013-11-01

    [Purpose] This study aimed to examine the effects of kinesio tape applied to chronic low back pain (CLBP) patients on anticipatory postural control and cerebral cortex potential. [Subjects and Methods] Twenty patients whose low back pain had continued for more than 12 weeks were selected and assigned to a control group (n=10) to which ordinary physical therapy was applied and an experimental group (n=10) to which kinesio tape was applied. Anticipatory postural control was evaluated using electromyography, and movement-related cortical potential (MRCP) was assessed using electroencephalography. Clinical evaluation was performed using a visual analogue scale and the Oswestry disability index. [Results] According to the analysis results for anticipatory postural control, there were significant decreases in the transversus abdominis (TrA) muscle and the external oblique muscle in both groups. Among them, the TrA of the experimental group exhibited the greatest differences. According to the results of a between-group comparison, there was significant difference in the TrA between the two groups. There was also a significant decrease in the MRCP of both groups. In particular, changes in the movement monitoring potential (MMP) of the experimental group were greatest at Fz, C3, Cz, and C4. According to the between-group comparison, there were significant differences in MMP at F3, C3, and Cz. Both groups saw VAS and ODI significantly decrease. Among them, the ODI of the experimental group underwent the greatest change. [Conclusion] Kinesio tape applied to CLBP patients reduced their pain and positively affected their anticipatory postural control and MRCP.

  18. The Effects of Kinesio Taping on Potential in Chronic Low Back Pain Patients Anticipatory Postural Control and Cerebral Cortex

    Science.gov (United States)

    Bae, Sea Hyun; Lee, Jeong Hun; Oh, Kyeong Ae; Kim, Kyung Yoon

    2013-01-01

    [Purpose] This study aimed to examine the effects of kinesio tape applied to chronic low back pain (CLBP) patients on anticipatory postural control and cerebral cortex potential. [Subjects and Methods] Twenty patients whose low back pain had continued for more than 12 weeks were selected and assigned to a control group (n=10) to which ordinary physical therapy was applied and an experimental group (n=10) to which kinesio tape was applied. Anticipatory postural control was evaluated using electromyography, and movement-related cortical potential (MRCP) was assessed using electroencephalography. Clinical evaluation was performed using a visual analogue scale and the Oswestry disability index. [Results] According to the