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Sample records for cerebral cortex neurons

  1. The Age of Human Cerebral Cortex Neurons

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    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. Morphological and functional correlates of VIP neurons in cerebral cortex

    International Nuclear Information System (INIS)

    Vasoactive Intestinal Polypeptide (VIP) promotes the hydrolysis of 3H-glycogen newly synthesized from 3H-glucose by mouse cortical slices. This effect occurs rapidly, approximately 50% of the maximal effect being reached within one minute. The maximal effect is achieved after 5 minutes and maintained for at least 25 minutes. Furthermore the glycogenolytic effect of VIP is reversible, and pharmacologically specific. Thus several neuropeptides present in cerebral cortex such as cholecystokinin-8, somatostatin-28, somatostatin-14, met-enkephalin, leu-enkephalin, do not affect 3H-glycogen levels. VIP fragments 6-28, 16-28 and 21-28 are similarly inactive. Furthermore, among the peptides which share structural homologies with VIP, such as glucagon, secretin, PHI-27 and Gastric Inhibitory Peptide, only secretin and PHI-27 promote 3H-glycogen hydrolysis, with EC50 of 500 and 300 nM respectively, compared to an EC50 of 25 nM for VIP. Immunohistochemical observations indicate that each VIP-containing bipolar cell is identified with a unique radical cortical volume, which is generally between 15-60 micrograms in diameter and overlaps with the contiguous domains of neighbouring VIP-containing bipolar cells. Thus this set of biochemical and morphological observations support the notion that VIP neurons have the capacity to regulate the availability of energy substrates in cerebral cortex locally, within circumscribed, contiguous, radial domains

  3. 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...

  4. Chronic Unpredictable Stress Promotes Neuronal Apoptosis in the Cerebral Cortex

    OpenAIRE

    Bachis, Alessia; Cruz, Maria Idalia; Nosheny, Rachael L.; Mocchetti, Italo

    2008-01-01

    Stress-mediated loss of synaptogenesis in the hippocampus appears to play a role in depressive and mood disorders. However, little is known about the effect of stress/depression on the plasticity and survival of cortical neurons. In this report, we have examined whether chronic stress increases the vulnerability of neurons in the rat cortex. We have used a chronic unpredictable mild stress (CMS) as a rat model of depression. CMS (5 weeks treatment) produced anedonia and increased corticostero...

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

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    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 ...

  6. 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.

  7. Dopamine receptor activation modulates GABA neuron migration from the basal forebrain to the cerebral cortex.

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    Crandall, James E; McCarthy, Deirdre M; Araki, Kiyomi Y; Sims, John R; Ren, Jia-Qian; Bhide, Pradeep G

    2007-04-01

    GABA neurons of the cerebral cortex and other telencephalic structures are produced in the basal forebrain and migrate to their final destinations during the embryonic period. The embryonic basal forebrain is enriched in dopamine and its receptors, creating a favorable environment for dopamine to influence GABA neuron migration. However, whether dopamine receptor activation can influence GABA neuron migration is not known. We show that dopamine D1 receptor activation promotes and D2 receptor activation decreases GABA neuron migration from the medial and caudal ganglionic eminences to the cerebral cortex in slice preparations of embryonic mouse forebrain. Slice preparations from D1 or D2 receptor knock-out mouse embryos confirm the findings. In addition, D1 receptor electroporation into cells of the basal forebrain and pharmacological activation of the receptor promote migration of the electroporated cells to the cerebral cortex. Analysis of GABA neuron numbers in the cerebral wall of the dopamine receptor knock-out mouse embryos further confirmed the effects of dopamine receptor activation on GABA neuron migration. Finally, dopamine receptor activation mobilizes striatal neuronal cytoskeleton in a manner consistent with the effects on neuronal migration. These data show that impairing the physiological balance between D1 and D2 receptors can alter GABA neuron migration from the basal forebrain to the cerebral cortex. The intimate relationship between dopamine and GABA neuron development revealed here may offer novel insights into developmental disorders such as schizophrenia, attention deficit or autism, and fetal cocaine exposure, all of which are associated with dopamine and GABA imbalance. PMID:17409246

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

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    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...

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

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    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

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

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    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...

  11. 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...

  12. 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.

  13. Effect of prenatal exposure to ethanol on the development of cerebral cortex: I. Neuronal generation

    International Nuclear Information System (INIS)

    Prenatal exposure to ethanol causes profound disruptions in the development of the cerebral cortex. Therefore, the effect of in utero ethanol exposure on the generation of neurons was determined. Pregnant rats were fed a liquid diet in which ethanol constituted 37.5% of the total caloric content (Et) or pair-fed an isocaloric control diet (Ct) from gestational day (GD) 6 to the day of birth. The time of origin of cortical neurons was determined in the mature pups of females injected with [3H]thymidine on one day during the period from GD 10 to the day of birth. The brains were processed by standard autoradiographic techniques. Ethanol exposure produced multiple defects in neuronal ontogeny. The period of generation was 1-2 days later for Et-treated rats than for rats exposed prenatally to either control diet. Moreover, the generation period was 1-2 days longer in Et-treated rats. The numbers of neurons generated on a specific day was altered; from GD 12-19 significantly fewer neurons were generated in Et-treated rats than in Ct-treated rats, whereas after GD 19 more neurons were born. The distribution of neurons generated on a specific day was disrupted; most notable was the distribution of late-generated neurons in deep cortex of Et-treated rats rather than in superficial cortex as they are in controls. Cortical neurons in Et-treated rats tended to be smaller than in Ct-treated rats, particularly early generated neurons in deep cortex. The late-generated neurons in Et-treated rats were of similar size to those in Ct-treated rats despite their abnormal position in deep cortex. Neurons in Ct-treated rats tended to be rounder than those in Et-treated rats which were more polarized in the radial orientation

  14. 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...

  15. 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...

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

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    T.R. Rahmy

    2004-01-01

    Full Text Available 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 after envenoming. Formalin-fixed paraffin sections were immunohistochemically studied by avidin-biotin-peroxidase complex method. Neuron histological structure and isolation of genomic DNA were also detected. The results showed a dose and time-dependent increase in NSE and SYN immunoreactivity in cerebral cortex of envenomed rats except in 72 hr high dose envenoming, where decreased SYN was observed. On the other hand, low dose venom induced high Bcl-2 expression 24 hr after envenoming, while the high dose decreased Bcl-2 protein expression. Temporal and spatial Bcl-2 expression was accompanied by DNA fragmentation in cerebral cortex of all envenomed rats, although no serious histological alterations were noticed. These results suggest that cobra venom may lead to neuronal injury and impairment of axonal transport as ascertained by alterations in NSE and SYN immunoreactivity. It could also indicate that venom alters the molecular machinery of apoptosis by inhibiting Bcl-2 expression; however, some vulnerable cells have the ability to overcome this by increasing Bcl-2 protein. These immunohistochemical investigations can be used as tools for detecting neuronal abnormalities even before the occurrence of any histological alterations in case of cerebral cortex neurotoxicity.

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

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    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

  18. Neuronal activity (c-Fos) delineating interactions of the cerebral cortex and basal ganglia

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    Mei-Hong Qiu; Chen, Michael C.; Zhi-Li Huang

    2014-01-01

    The cerebral cortex and basal ganglia (BG) form a neural circuit that is disrupted in disorders such as Parkinson’s disease. We found that neuronal activity (c-Fos) in the BG followed cortical activity, i.e., high in arousal state and low in sleep state. To determine if cortical activity is necessary for BG activity, we administered atropine to rats to induce a dissociative state resulting in slow-wave EEG but hyperactive motor behaviors. Atropine blocked c-Fos expression in the cortex and BG...

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

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    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.

  20. 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

  1. Neuronal activity (c-Fos) delineating interactions of the cerebral cortex and basal ganglia

    OpenAIRE

    Qiu, Mei-Hong; Chen, Michael C.; Huang, Zhi-Li; Lu, Jun

    2014-01-01

    The cerebral cortex and basal ganglia (BG) form a neural circuit that is disrupted in disorders such as Parkinson’s disease. We found that neuronal activity (c-Fos) in the BG followed cortical activity, i.e., high in arousal state and low in sleep state. To determine if cortical activity is necessary for BG activity, we administered atropine to rats to induce a dissociative state resulting in slow-wave electroencephalography but hyperactive motor behaviors. Atropine blocked c-Fos expression i...

  2. The lizard cerebral cortex as a model to study neuronal regeneration

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    CARLOS LOPEZ-GARCIA

    2002-03-01

    Full Text Available The medial cerebral cortex of lizards, an area homologous to the hippocampal fascia dentata, shows delayed postnatal neurogenesis, i.e., cells in the medial cortex ependyma proliferate and give rise to immature neurons, which migrate to the cell layer. There, recruited neurons differentiate and give rise to zinc containing axons directed to the rest of cortical areas, thus resulting in a continuous growth of the medial cortex and its zinc-enriched axonal projection. This happens along the lizard life span, even in adult lizards, thus allowing one of their most important characteristics: neuronal regeneration. Experiments in our laboratory have shown that chemical lesion of the medial cortex (affecting up to 95% of its neurons results in a cascade of events: first, massive neuronal death and axonal-dendritic retraction and, secondly, triggered ependymal-neuroblast proliferation and subsequent neo-histogenesis and regeneration of an almost new medial cortex, indistinguishable from a normal undamaged one. This is the only case to our knowledge of the regeneration of an amniote central nervous centre by new neuron production and neo-histogenesis. Thus the lizard cerebral cortex is a good model to study neuronal regeneration and the complex factors that regulate its neurogenetic, migratory and neo-synaptogenetic events.O córtex cerebral de lagartos, uma área homóloga à fascia dentata hipocampal, exibe neurogênese pós-natal prolongada, isto é, o epêndima do córtex medial prolifera e dá origem a neurônios imaturos, que migram para a camada celular. Nesta camada, neurônios recrutados se diferenciam e dão origem a axônios, ricos em zinco, que se projetam para as demais áreas corticais, do que resulta um crescimento contínuo do córtex medial e sua projeção axonal. Isto acontece por toda a vida do lagarto, mesmo em animais adultos, o que permite uma de suas características mais importantes: a regeneração neuronal. Experimentos em

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

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    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.

  4. Human Cerebral Cortex Cajal-Retzius Neuron: Development, Structure and Function. A Golgi Study

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    Miguel Marín-Padilla

    2015-02-01

    Full Text Available The development, morphology and possible functional activity of the Cajal-Retzius cell of the developing human cerebral cortex have been explored herein. The C-RC, of extracortical origin, is the essential neuron of the neocortex first lamina. It receives inputs from subcortical afferent fibers that reach the first lamina early in development. Although the origin and function of these original afferent fibers remain unknown, they target the first lamina sole neuron: the C-RC. The neuron’ orchestrates the arrival, size and stratification of all pyramidal neurons (from ependymal origin of the neocortex gray matter. Its axonic terminals spread radially and horizontally throughout the entire first lamina establishing contacts with the dendritic terminals of all gray matter pyramidal cells regardless of size, location and/or eventual functional roles. While the neuron axonic terminals spread radially and horizontally throughout the first lamina, the neuron’ bodies undergoes progressive developmental dilution and locating any of them in the adult brain become quite difficult. The neuron bodies are probably retained in the older regions of the developing neocortex while their axonic collaterals will spread throughout its more recent ones that, eventually, will represent the great majority of the brain surface. This will explain their bodies progressive dilution in the developing neocortex and, later, in the adult brain. Although quite difficult to locate the body of any of them, they have been described in the adult brain.

  5. Low level prenatal exposure to methylmercury disrupts neuronal migration in the developing rat cerebral cortex

    International Nuclear Information System (INIS)

    Highlights: ► Low level MeHg exposure causes migratory defect of rat cerebrocortical neurons. ► The migration defect is due to the impact of MeHg on the neuronal migration itself. ► Rho GTPases seem to be involved in MeHg-induced disruption of neuronal migration. -- Abstract: We determined the effects of low-level prenatal MeHg exposure on neuronal migration in the developing rat cerebral cortex using in utero electroporation. We used offspring rats born to dams that had been exposed to saline or various doses of MeHg (0.01 mg/kg/day, 0.1 mg/kg/day, and 1 mg/kg/day) from gestational day (GD) 11–21. Immunohistochemical examination of the brains of the offspring was conducted on postnatal day (PND) 0, PND3, and PND7. Our results showed that prenatal exposure to low levels of MeHg (0.1 mg/kg/day or 1 mg/kg/day) during the critical stage in neuronal migration resulted in migration defects of the cerebrocortical neurons in offspring rats. Importantly, our data revealed that the abnormal neuronal distribution induced by MeHg was not caused by altered proliferation of neural progenitor cells (NPCs), induction of apoptosis of NPCs and/or newborn neurons, abnormal differentiation of NPCs, and the morphological changes of radial glial scaffold, indicating that the defective neuronal positioning triggered by exposure to low-dose of MeHg is due to the impacts of MeHg on the process of neuronal migration itself. Moreover, we demonstrated that in utero exposure to low-level MeHg suppresses the expression of Rac1, Cdc42, and RhoA, which play key roles in the migration of cerebrocortical neurons during the early stage of brain development, suggesting that the MeHg-induced migratory disturbance of cerebrocortical neurons is likely associated with the Rho GTPases signal pathway. In conclusion, our results provide a novel perspective on clarifying the mechanisms underlying the impairment of neuronal migration induced by MeHg

  6. Neuronal activity (c-Fos delineating interactions of the cerebral cortex and basal ganglia

    Directory of Open Access Journals (Sweden)

    Mei-Hong Qiu

    2014-03-01

    Full Text Available The cerebral cortex and basal ganglia (BG form a neural circuit that is disrupted in disorders such as Parkinson’s disease. We found that neuronal activity (c-Fos in the BG followed cortical activity, i.e., high in arousal state and low in sleep state. To determine if cortical activity is necessary for BG activity, we administered atropine to rats to induce a dissociative state resulting in slow-wave EEG but hyperactive motor behaviors. Atropine blocked c-Fos expression in the cortex and BG, despite high c-Fos expression in the sub-cortical arousal neuronal groups and thalamus, indicating that cortical activity is required for BG activation. To identify which glutamate receptors in the BG that mediate cortical inputs, we injected ketamine (NMDA receptor antagonist and 6-cyano-nitroquinoxaline-2, 3-dione (CNQX, a non-NMDA receptor antagonist. Systemic ketamine and CNQX administration revealed that NMDA receptors mediated subthalamic nucleus (STN input to internal globus pallidus (GPi and substantia nigra pars reticulata (SNr, while non-NMDA receptor mediated cortical input to the STN. Both types of glutamate receptors were involved in mediating cortical input to the striatum. Dorsal striatal (caudoputamen, CPu dopamine depletion by 6-hydroxydopamine resulted in reduced activity of the CPu, globus pallidus externa (GPe, and STN but increased activity of the GPi, SNr and putative layer V neurons in the motor cortex. Our results reveal that the cortical activity is necessary for BG activity and clarifies the pathways and properties of the BG-cortical network and their putative role in the pathophysiology of BG disorders.

  7. Chemical interactions with pyramidal neurons in layer 5 of the cerebral cortex: control of pain and anxiety.

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    Adams, J D

    2009-01-01

    Pyramidal neurons in layer 5 of the cerebral cortex are involved in learning and memory and have complex connections with other neurons through a very large array of dendrites. These dendrites can switch between long term depression and long term potentiation depending on global summation of various inputs. The plasticity of the input into pyramidal neurons makes the neuronal output variable. Many interneurons in the cerebral cortex and distant neurons in other brain regions are involved in providing input to pyramidal neurons. All of these neurons and interneurons have neurotransmitters that act through receptors to provide input to pyramidal neurons. Serotonin is one of the important neurotransmitters involved with pyramidal neurons and has been implicated in psychosis, psychedelic states and what are called sacred dreams. This review will discuss the various chemicals and receptors that are important with pyramidal neurons including opioids, nicotine, scopolamine, psilocybin, LSD, mescaline, ergot alkaloids, salvinorin A, ergine and other compounds that interact with opioid, nicotinic, muscarinic and serotonergic receptors. The natural compounds provide clues to structure activity relationships with the receptors. It has been postulated that each receptor in the body has a natural agonist and antagonist, in addition to the normal neurotransmitters. It is common for natural antagonists and agonists to be peptides. Various possible peptide structures will be proposed for natural antagonists and agonists at each receptor. Natural antagonists and agonists may provide new ways to explore the functions of pyramidal neurons in normal health and pain management. PMID:19799545

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

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    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...

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

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    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...

  10. Sox2-Mediated Conversion of NG2 Glia into Induced Neurons in the Injured Adult Cerebral Cortex

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    Christophe Heinrich

    2014-12-01

    Full Text Available The adult cerebral cortex lacks the capacity to replace degenerated neurons following traumatic injury. Conversion of nonneuronal cells into induced neurons has been proposed as an innovative strategy toward brain repair. Here, we show that retrovirus-mediated expression of the transcription factors Sox2 and Ascl1, but strikingly also Sox2 alone, can induce the conversion of genetically fate-mapped NG2 glia into induced doublecortin (DCX+ neurons in the adult mouse cerebral cortex following stab wound injury in vivo. In contrast, lentiviral expression of Sox2 in the unlesioned cortex failed to convert oligodendroglial and astroglial cells into DCX+ cells. Neurons induced following injury mature morphologically and some acquire NeuN while losing DCX. Patch-clamp recording of slices containing Sox2- and/or Ascl1-transduced cells revealed that a substantial fraction of these cells receive synaptic inputs from neurons neighboring the injury site. Thus, NG2 glia represent a potential target for reprogramming strategies toward cortical repair.

  11. 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...

  12. 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

  13. 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.

  14. 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.

  15. 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

  16. 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

  17. 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

  18. 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.

  19. 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

  20. DNA methylation in the human cerebral cortex is dynamically regulated throughout the life span and involves differentiated neurons.

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    Kimberly D Siegmund

    Full Text Available The role of DNA cytosine methylation, an epigenetic regulator of chromatin structure and function, during normal and pathological brain development and aging remains unclear. Here, we examined by MethyLight PCR the DNA methylation status at 50 loci, encompassing primarily 5' CpG islands of genes related to CNS growth and development, in temporal neocortex of 125 subjects ranging in age from 17 weeks of gestation to 104 years old. Two psychiatric disease cohorts--defined by chronic neurodegeneration (Alzheimer's or lack thereof (schizophrenia--were included. A robust and progressive rise in DNA methylation levels across the lifespan was observed for 8/50 loci (GABRA2, GAD1, HOXA1, NEUROD1, NEUROD2, PGR, STK11, SYK typically in conjunction with declining levels of the corresponding mRNAs. Another 16 loci were defined by a sharp rise in DNA methylation levels within the first few months or years after birth. Disease-associated changes were limited to 2/50 loci in the Alzheimer's cohort, which appeared to reflect an acceleration of the age-related change in normal brain. Additionally, methylation studies on sorted nuclei provided evidence for bidirectional methylation events in cortical neurons during the transition from childhood to advanced age, as reflected by significant increases at 3, and a decrease at 1 of 10 loci. Furthermore, the DNMT3a de novo DNA methyl-transferase was expressed across all ages, including a subset of neurons residing in layers III and V of the mature cortex. Therefore, DNA methylation is dynamically regulated in the human cerebral cortex throughout the lifespan, involves differentiated neurons, and affects a substantial portion of genes predominantly by an age-related increase.

  1. 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.

  2. 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...

  3. 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. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 76: 600-614, 2016. PMID:26297819

  4. 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

  5. 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.

  6. Total number and volume of Von Economo neurons in the cerebral cortex of cetaceans

    OpenAIRE

    Butti, Camilla; Sherwood, Chet C.; Hakeem, Atiya Y.; Allman, John M.; Hof, Patrick R

    2009-01-01

    Von Economo neurons (VENs) are a type of large, layer V spindle-shaped neurons that were previously described in humans, great apes, elephants, and some large-brained cetaceans. Here we report the presence of Von Economo neurons in the anterior cingulate (ACC), anterior insular (AI), and frontopolar (FP) cortices of small odontocetes, including the bottlenose dolphin (Tursiops truncatus), the Risso's dolphin (Grampus griseus), and the beluga whale (Delphinapterus leucas). The total number and...

  7. Decision-Related Activity in Sensory Neurons May Depend on the Columnar Architecture of Cerebral Cortex

    OpenAIRE

    Nienborg, H.; Cumming, B.G.

    2014-01-01

    Many studies have reported correlations between the activity of sensory neurons and animals' judgments in discrimination tasks. Here, we suggest that such neuron-behavior correlations may require a cortical map for the task relevant features. This would explain why studies using discrimination tasks based on disparity in area V1 have not found these correlations: V1 contains no map for disparity. This scheme predicts that activity of V1 neurons correlates with decisions in an orientation-disc...

  8. Contributions of Diverse Excitatory and Inhibitory Neurons to Recurrent Network Activity in Cerebral Cortex

    OpenAIRE

    Neske, Garrett T.; Patrick, Saundra L.; Connors, Barry W.

    2015-01-01

    The recurrent synaptic architecture of neocortex allows for self-generated network activity. One form of such activity is the Up state, in which neurons transiently receive barrages of excitatory and inhibitory synaptic inputs that depolarize many neurons to spike threshold before returning to a relatively quiescent Down state. The extent to which different cell types participate in Up states is still unclear. Inhibitory interneurons have particularly diverse intrinsic properties and synaptic...

  9. 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.

  10. Subplate Cells: Amplifiers of Neuronal Activity in the Developing Cerebral Cortex

    Science.gov (United States)

    Luhmann, Heiko J.; Kilb, Werner; Hanganu-Opatz, Ileana L.

    2009-01-01

    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 non-synaptic 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 10–20 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. PMID:19862346

  11. 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...

  12. 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

  13. Decision-related activity in sensory neurons may depend on the columnar architecture of cerebral cortex.

    Science.gov (United States)

    Nienborg, Hendrikje; Cumming, Bruce G

    2014-03-01

    Many studies have reported correlations between the activity of sensory neurons and animals' judgments in discrimination tasks. Here, we suggest that such neuron-behavior correlations may require a cortical map for the task relevant features. This would explain why studies using discrimination tasks based on disparity in area V1 have not found these correlations: V1 contains no map for disparity. This scheme predicts that activity of V1 neurons correlates with decisions in an orientation-discrimination task. To test this prediction, we trained two macaque monkeys in a coarse orientation discrimination task using band-pass-filtered dynamic noise. The two orientations were always 90° apart and task difficulty was controlled by varying the orientation bandwidth of the filter. While the trained animals performed this task, we recorded from orientation-selective V1 neurons (n = 82, n = 31 for Monkey 1, n = 51 for Monkey 2). For both monkeys, we observed significant correlation (quantified as "choice probabilities") of the V1 activity with the monkeys' perceptual judgments (mean choice probability 0.54, p = 10(-5)). In one of these animals, we had previously measured choice probabilities in a disparity discrimination task in V1, which had been at chance (0.49, not significantly different from 0.5). The choice probabilities in this monkey for the orientation discrimination task were significantly larger than those for the disparity discrimination task (p = 0.032). These results are predicted by our suggestion that choice probabilities are only observed for cortical sensory neurons that are organized in maps for the task-relevant feature. PMID:24599457

  14. 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

  15. 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.

  16. 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.

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. 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. PMID:24434608

  2. 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. PMID:27034844

  3. [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

  4. Disminución del número de neuronas que expresan GABA en la corteza cerebral de ratones infectados con rabia Decreased number neurons expressing GABA in the cerebral cortex of rabies-infected mice

    Directory of Open Access Journals (Sweden)

    Orlando Torres-Fernández

    2007-12-01

    have suggested that rabies viral infections affect the host GABAergic system.
    Objective. The effect of rabies virus infection on the expression of GABA was evaluated in neurons of the mouse cerebral cortex.
    Materials and methods. Adult mice were inoculated by intramuscular injection with the standard strain of rabies (CVS virus. The animals were sacrificed in the terminal stage of the illness and perfused with 4% paraformaldehyde and 1% glutaraldehyde. Frontal sections were obtained in a Vibratome® and treated with appropriate immunohistochemical reactions for identifying the GABAergic neurons in the cerebral cortex. Counts and comparative quantitative analysis of the GABA+ neurons were compared in samples of infected and normal mice.
    Results. In the animals infected with rabies virus, the distribution pattern of cortical GABAergic neurons was not changed, but their number diminished significantly. The mean value of GABA+ cells number in 1 μm2 of cerebral cortex was 293±32 in normal samples and 209±13 in infected samples. Despite the loss in GABA+ cell number, the average size of GABA+ cells per unit increased from 104±8 μm2 in normal mice to 122±10 μm2 in infected mice because the cell loss consisted more frequently of smaller neurons. Nevertheless, the rank of GABA+ cell sizes in infected samples was similar to normal samples.
    Conclusion. This evidence supported the hypothesis that GABA is involved in rabies pathology.

  5. 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...

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. Canonical computations of cerebral cortex.

    Science.gov (United States)

    Miller, Kenneth D

    2016-04-01

    The idea that there is a fundamental cortical circuit that performs canonical computations remains compelling though far from proven. Here we review evidence for two canonical operations within sensory cortical areas: a feedforward computation of selectivity; and a recurrent computation of gain in which, given sufficiently strong external input, perhaps from multiple sources, intracortical input largely, but not completely, cancels this external input. This operation leads to many characteristic cortical nonlinearities in integrating multiple stimuli. The cortical computation must combine such local processing with hierarchical processing across areas. We point to important changes in moving from sensory cortex to motor and frontal cortex and the possibility of substantial differences between cortex in rodents vs. species with columnar organization of selectivity. PMID:26868041

  11. 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 ...

  12. 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. PMID:22572769

  13. 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

  14. 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

  15. 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.

  16. Translaminar Inhibitory Cells Recruited by Layer 6 Cortico-Thalamic Neurons Suppress Visual Cortex

    OpenAIRE

    Bortone, Dante S.; Olsen, Shawn R.; Scanziani, Massimo

    2014-01-01

    In layer 6 (L6), a principal output layer of the mammalian cerebral cortex, a population of excitatory neurons defined by the NTSR1-Cre mouse line inhibit cortical responses to visual stimuli. Here we show that of the two major types of excitatory neurons existing in L6, the NTSR1-Cre line selectively targets those whose axon innervate both cortex and thalamus and not those whose axons remain within the cortex. These cortico-thalamic neurons mediate widespread inhibition across all cortical l...

  17. Patterning the cerebral cortex: traveling with morphogens.

    Science.gov (United States)

    Borello, Ugo; Pierani, Alessandra

    2010-08-01

    The neocortex represents the brain structure that has been subjected to a major expansion in its relative size during the course of mammalian evolution. An exquisite coordination of appropriate growth of competent territories along multiple axes and their spatial patterning is required for regionalization of the cortical primordium and the formation of functional areas. The achievement of such a highly complex architecture relies on a precise orchestration of the proliferation of progenitors, onset of neurogenesis, spatio-temporal generation of distinct cell types and control of their migration. We will review recent work on alternative molecular mechanisms that, via the migration of signaling cells/structures, participate in coordinating growth and spatial patterning in the developing cerebral cortex. By integrating temporal and spatial parameters as well as absolute levels of signaling this novel strategy might represent a general mechanism for long-range patterning in large structures, in addition to the passive diffusion of morphogens. PMID:20542680

  18. 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.

  19. 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...

  20. 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

  1. 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

  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. Endogenous neurotransmitter activates N-methyl-D-aspartate receptors on differentiating neurons in embryonic cortex.

    OpenAIRE

    Blanton, M G; Lo Turco, J J; Kriegstein, A R

    1990-01-01

    Before synapses form in embryonic turtle cerebral cortex, an endogenous neurotransmitter activates N-methyl-D-aspartate (NMDA) channels on neurons in the cortical plate. Throughout cortical development, these channels exhibit voltage-dependent Mg2+ blockade and are antagonized by D-2-amino-5-phosphonovaleric acid, a selective NMDA receptor antagonist. The activation in situ of these nonsynaptic NMDA channels demonstrates a potential physiological substrate for control of early neuronal differ...

  5. Local production of astrocytes in the cerebral cortex.

    Science.gov (United States)

    Ge, W-P; Jia, J-M

    2016-05-26

    Astrocytes are the largest glial population in the mammalian brain. Astrocytes in the cerebral cortex are reportedly generated from four sources, namely radial glia, progenitors in the subventricular zone (SVZ progenitors), locally proliferating glia, and NG2 glia; it remains an open question, however, as to what extent these four cell types contribute to the substantial increase in astrocytes that occurs postnatally in the cerebral cortex. Here we summarize all possible sources of astrocytes and discuss their roles in this postnatal increase. In particular, we focus on astrocytes derived from local proliferation within the cortex. PMID:26343293

  6. 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

  7. 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

  8. 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...

  9. 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...

  10. 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.

  11. The Distribution of MAP-2 Phosphorylation in Cerebral Cortex of Long-Tailed Monkey Fetuses (Macaca fascicularis in the Last Trimester of Gestation

    Directory of Open Access Journals (Sweden)

    Tri Wahyu Pangestiningsih

    2015-11-01

    Full Text Available Memories are storage in cholinoceptive cells, the cells which are enriched with microtubule-associated protein 2 (MAP-2 that localized in the neuronal dendrite and the cell bodies. Phosphorylation of MAP-2 may increase memory with reduce stability of dendrite by altered dendrite length and lead new side-branches of neuronal as a neuronal plasticity processes in cerebral cortex. The aim of this research is to study the distribution of MAP-2 phosphorylation neurons in cerebral cortex of long-tailed macaques in the third semester of gestationalimmunohistochemically using avidin biotin conjugated complex method. Neurons MAP-2 phosphorylation immunoreactive were located in dendrites and cell bodies, mostly in pyramidal neurons of cerebral cortex. Intensity of MAP-2 phosphorylation immunoreactivity in layer V were stronger than another layer and the neurons that very intensely stained were the pyramidal cells in frontal and parietal lobes, that was suggested that neurons in this areas more responsive to neuroplasticity. From the results we concluded that MAP-2 phosphorylation already distributed in the cerebral cortex of long-tailed macaque fetuses at the last trimester of gestation, mostly in the pyramidal cells of layer V that is suggested plays a role for preparation of memoryformation.Keywords: fetus, long-tailed monkey, cerebral cortex, memory, MAP-2 phosphorylation

  12. 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

  13. Mapping the structural core of human cerebral cortex.

    OpenAIRE

    Hagmann, Patric; Cammoun, Leila; Gigandet, Xavier; Meuli, Reto; Honey, Christopher J.; Sporns, Olaf; Wedeen, Van Jay

    2008-01-01

    Author Summary In the human brain, neural activation patterns are shaped by the underlying structural connections that form a dense network of fiber pathways linking all regions of the cerebral cortex. Using diffusion imaging techniques, which allow the noninvasive mapping of fiber pathways, we constructed connection maps covering the entire cortical surface. Computational analyses of the resulting complex brain network reveal regions of cortex that are highly connected and highly central, fo...

  14. 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.

  15. Microtubules in the Cerebral Cortex: Role in Memory and Consciousness

    Science.gov (United States)

    Woolf, Nancy J.

    This chapter raises the question whether synaptic connections in the cerebral cortex are adequate in accounting for higher cognition, especially cognition involving multimodal processing. A recent and novel approach to brain mechanics is outlined, one that involves microtubules and microtubule-associated protein-2 (MAP2). In addition to effects on the neuronal membrane, neurotransmitters exert actions on microtubules. These neurotransmitter effects alter the MAP2 phosphorylation state and rates of microtubule polymerization and transport. It is argued that these processes are important to the physical basis of memory and consciousness. In support of this argument, MAP2 is degraded with learning in discrete cortical modules. How this relates to synaptic change related to learning is unknown. The specific proposal is advanced that learning alters microtubules in the subsynaptic zone lying beneath the synapse, and that this forms the physical basis of long-term memory storage because microtubule networks determine the synapse strength by directing contacts with actin filaments and transport of synaptic proteins. It is argued that this is more probable than memory-related physical storage in the synapse itself. Comparisons to consciousness are made and it is concluded that there is a link between microtubules, memory and consciousness.

  16. Tocilizumab inhibits neuronal cell apoptosis and activates STAT3 in cerebral infarction rat model

    Science.gov (United States)

    Wang, Shaojun; Zhou, Jun; Kang, Weijie; Dong, Zhaoni; Wang, Hezuo

    2016-01-01

    Cerebral infarction is a severe hypoxic ischemic necrosis with accelerated neuronal cell apoptosis in the brain. As a monoclonal antibody against interleukin 6, tocilizumab (TCZ) is widely used in immune diseases, whose function in cerebral infarction has not been studied. This study aims to reveal the role of TCZ in regulating neuronal cell apoptosis in cerebral infarction. The cerebral infarction rat model was constructed by middle cerebral artery occlusion and treated with TCZ. Cell apoptosis in hippocampus and cortex of the brain was examined with TUNEL method. Rat neuronal cells cultured in oxygen-glucose deprivation (OGD) conditions and treated with TCZ were used to compare cell viability and apoptosis. Apoptosis-related factors including B-cell lymphoma extra large (Bcl-xL) and Caspase 3, as well as the phosphorylated signal transducer and activator of transcription 3 (p-STAT3) in brain cortex were analyzed from the protein level. Results indicated that TCZ treatment could significantly prevent the promoted cell apoptosis caused by cerebral infarction or OGD (P < 0.05 or P < 0.01). In brain cortex of the rat model, TCZ up-regulated Bcl-xL and down-regulated Caspase 3, consistent with the inhibited cell apoptosis. It also promoted tyrosine 705 phosphorylation of STAT3, which might be the potential regulatory mechanism of TCZ in neuronal cells. This study provided evidence for the protective role of TCZ against neuronal cell apoptosis in cerebral infarction. Based on these fundamental data, TCZ is a promising option for treating cerebral infarction, but further investigations on related mechanisms are still necessary. PMID:26773188

  17. 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.

  18. 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.

  19. 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...

  20. 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...

  1. 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.

  2. 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.

  3. 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.

  4. 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

  5. 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

  6. Developmental malformations of the cerebral cortex

    International Nuclear Information System (INIS)

    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.)

  7. 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

  8. 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.

  9. Responses of primate frontal cortex neurons during natural vocal communication.

    Science.gov (United States)

    Miller, Cory T; Thomas, A Wren; Nummela, Samuel U; de la Mothe, Lisa A

    2015-08-01

    The role of primate frontal cortex in vocal communication and its significance in language evolution have a controversial history. While evidence indicates that vocalization processing occurs in ventrolateral prefrontal cortex neurons, vocal-motor activity has been conjectured to be primarily subcortical and suggestive of a distinctly different neural architecture from humans. Direct evidence of neural activity during natural vocal communication is limited, as previous studies were performed in chair-restrained animals. Here we recorded the activity of single neurons across multiple regions of prefrontal and premotor cortex while freely moving marmosets engaged in a natural vocal behavior known as antiphonal calling. Our aim was to test whether neurons in marmoset frontal cortex exhibited responses during vocal-signal processing and/or vocal-motor production in the context of active, natural communication. We observed motor-related changes in single neuron activity during vocal production, but relatively weak sensory responses for vocalization processing during this natural behavior. Vocal-motor responses occurred both prior to and during call production and were typically coupled to the timing of each vocalization pulse. Despite the relatively weak sensory responses a population classifier was able to distinguish between neural activity that occurred during presentations of vocalization stimuli that elicited an antiphonal response and those that did not. These findings are suggestive of the role that nonhuman primate frontal cortex neurons play in natural communication and provide an important foundation for more explicit tests of the functional contributions of these neocortical areas during vocal behaviors. PMID:26084912

  10. 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

  11. 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.

  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. Dynamic gene expression in the human cerebral cortex distinguishes children from adults.

    Science.gov (United States)

    Sterner, Kirstin N; Weckle, Amy; Chugani, Harry T; Tarca, Adi L; Sherwood, Chet C; Hof, Patrick R; Kuzawa, Christopher W; Boddy, Amy M; Abbas, Asad; Raaum, Ryan L; Grégoire, Lucie; Lipovich, Leonard; Grossman, Lawrence I; Uddin, Monica; Goodman, Morris; Wildman, Derek E

    2012-01-01

    In comparison with other primate species, humans have an extended juvenile period during which the brain is more plastic. In the current study we sought to examine gene expression in the cerebral cortex during development in the context of this adaptive plasticity. We introduce an approach designed to discriminate genes with variable as opposed to uniform patterns of gene expression and found that greater inter-individual variance is observed among children than among adults. For the 337 transcripts that show this pattern, we found a significant overrepresentation of genes annotated to the immune system process (pFDR ~/= 0). Moreover, genes known to be important in neuronal function, such as brain-derived neurotrophic factor (BDNF), are included among the genes more variably expressed in childhood. We propose that the developmental period of heightened childhood neuronal plasticity is characterized by more dynamic patterns of gene expression in the cerebral cortex compared to adulthood when the brain is less plastic. That an overabundance of these genes are annotated to the immune system suggests that the functions of these genes can be thought of not only in the context of antigen processing and presentation, but also in the context of nervous system development. PMID:22666384

  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. 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

  18. 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.

  19. 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.

  20. 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

  1. 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

  2. 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

  3. 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.

  4. Structure and plasticity potential of neural networks in the cerebral cortex

    Science.gov (United States)

    Fares, Tarec Edmond

    In this thesis, we first described a theoretical framework for the analysis of spine remodeling plasticity. We provided a quantitative description of two models of spine remodeling in which the presence of a bouton is either required or not for the formation of a new synapse. We derived expressions for the density of potential synapses in the neuropil, the connectivity fraction, which is the ratio of actual to potential synapses, and the number of structurally different circuits attainable with spine remodeling. We calculated these parameters in mouse occipital cortex, rat CA1, monkey V1, and human temporal cortex. We found that on average a dendritic spine can choose among 4-7 potential targets in rodents and 10-20 potential targets in primates. The neuropil's potential for structural circuit remodeling is highest in rat CA1 (7.1-8.6 bits/mum3) and lowest in monkey V1 (1.3-1.5 bits/mum 3 We next studied the role neuron morphology plays in defining synaptic connectivity. As previously stated it is clear that only pairs of neurons with closely positioned axonal and dendritic branches can be synaptically coupled. For excitatory neurons in the cerebral cortex, ). We also evaluated the lower bound of neuron selectivity in the choice of synaptic partners. Post-synaptic excitatory neurons in rodents make synaptic contacts with more than 21-30% of pre-synaptic axons encountered with new spine growth. Primate neurons appear to be more selective, making synaptic connections with more than 7-15% of encountered axons. We next studied the role neuron morphology plays in defining synaptic connectivity. As previously stated it is clear that only pairs of neurons with closely positioned axonal and dendritic branches can be synaptically coupled. For excitatory neurons in the cerebral cortex, such axo-dendritic oppositions, or potential synapses, must be bridged by dendritic spines to form synaptic connections. To explore the rules by which synaptic connections are formed within

  5. Effects of anesthesia on BOLD signal and neuronal activity in the somatosensory cortex.

    Science.gov (United States)

    Aksenov, Daniil P; Li, Limin; Miller, Michael J; Iordanescu, Gheorghe; Wyrwicz, Alice M

    2015-11-01

    Most functional magnetic resonance imaging (fMRI) animal studies rely on anesthesia, which can induce a variety of drug-dependent physiological changes, including depression of neuronal activity and cerebral metabolism as well as direct effects on the vasculature. The goal of this study was to characterize the effects of anesthesia on the BOLD signal and neuronal activity. Simultaneous fMRI and electrophysiology were used to measure changes in single units (SU), multi-unit activity (MUA), local field potentials (LFP), and the blood oxygenation level-dependent (BOLD) response in the somatosensory cortex during whisker stimulation of rabbits before, during and after anesthesia with fentanyl or isoflurane. Our results indicate that anesthesia modulates the BOLD signal as well as both baseline and stimulus-evoked neuronal activity, and, most significantly, that the relationship between the BOLD and electrophysiological signals depends on the type of anesthetic. Specifically, the behavior of LFP observed under isoflurane did not parallel the behavior of BOLD, SU, or MUA. These findings suggest that the relationship between these signals may not be straightforward. BOLD may scale more closely with the best measure of the excitatory subcomponents of the underlying neuronal activity, which may vary according to experimental conditions that alter the excitatory/inhibitory balance in the cortex. PMID:26104288

  6. 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....

  7. Pyruvate treatment attenuates cerebral metabolic depression and neuronal loss after experimental traumatic brain injury.

    Science.gov (United States)

    Moro, Nobuhiro; Ghavim, Sima S; Harris, Neil G; Hovda, David A; Sutton, Richard L

    2016-07-01

    Experimental traumatic brain injury (TBI) is known to produce an acute increase in cerebral glucose utilization, followed rapidly by a generalized cerebral metabolic depression. The current studies determined effects of single or multiple treatments with sodium pyruvate (SP; 1000mg/kg, i.p.) or ethyl pyruvate (EP; 40mg/kg, i.p.) on cerebral glucose metabolism and neuronal injury in rats with unilateral controlled cortical impact (CCI) injury. In Experiment 1 a single treatment was given immediately after CCI. SP significantly improved glucose metabolism in 3 of 13 brain regions while EP improved metabolism in 7 regions compared to saline-treated controls at 24h post-injury. Both SP and EP produced equivalent and significant reductions in dead/dying neurons in cortex and hippocampus at 24h post-CCI. In Experiment 2 SP or EP were administered immediately (time 0) and at 1, 3 and 6h post-CCI. Multiple SP treatments also significantly attenuated TBI-induced reductions in cerebral glucose metabolism (in 4 brain regions) 24h post-CCI, as did multiple injections of EP (in 4 regions). The four pyruvate treatments produced significant neuroprotection in cortex and hippocampus 1day after CCI, similar to that found with a single SP or EP treatment. Thus, early administration of pyruvate compounds enhanced cerebral glucose metabolism and neuronal survival, with 40mg/kg of EP being as effective as 1000mg/kg of SP, and multiple treatments within 6h of injury did not improve upon outcomes seen following a single treatment. PMID:27059390

  8. 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

  9. 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

  10. 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

  11. 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...

  12. 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.

  13. [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

  14. 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

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

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    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.

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

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    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.

  17. 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

  18. [Nuclear and cytoplasmic RNA in visual cortex neurons of adult rats following visual deprivation and photic stimulation].

    Science.gov (United States)

    Malinauskaite, L D

    1980-10-01

    It has been shown by two-wavelength cytospectrophotometry of gallocyanin-chrome alum-stained sections that visual deprivation in adult rats kept in a complete darkness for 30 days resulted in an accumulation of cytoplasmic RNA by layer V neurons of the visual cerebral cortex and by the cells of the perineuronal neuroglia of this layer. The nuclear RNA content remained unchanged. Stimulation of intact rats with a flickering or constant light induced an increase in the cytoplasmic RNA in these neurons rather than in the nuclear RNA as well as in RNA in their glial satellite cells. Similar light stimulation of the deprived animals gave rise to a complete return of the neuronal RNA to normal with only a slight decrease in the deprivation-induced RNA accumulation by the neuroglial cells. Neither visual deprivation nor light stimulation affected the RNA content in the neurons and neuroglia of layer V of the motor cerebral cortex. Compartmentation of RNA metabolism within the neuronal-neuroglial unit is discussed. PMID:6159015

  19. 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.

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

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    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.

  1. Lower motor neuron facial palsy in cerebral venous sinus thrombosis

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    Girish Baburao Kulkarni

    2013-01-01

    Full Text Available With advances in the neuro-imaging modalities, diverse manifestations of the cerebral venous sinus thrombosis (CVT are being recognized. There are very few reports of isolated cranial nerve palsies in CVT. In this case report, we describe a patient of lower motor neuron facial palsy with CVT who was successfully treated with anticoagulation, highlighting the atypical manifestation of the disease.

  2. 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

  3. Understanding the Dorsal and Ventral Systems of the Human Cerebral Cortex: Beyond Dichotomies

    Science.gov (United States)

    Borst, Gregoire; Thompson, William L.; Kosslyn, Stephen M.

    2011-01-01

    Traditionally, characterizations of the macrolevel functional organization of the human cerebral cortex have focused on the left and right cerebral hemispheres. However, the idea of left brain versus right brain functions has been shown to be an oversimplification. We argue here that a top-bottom divide, rather than a left-right divide, is a more…

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

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    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.

  5. Network structure of cerebral cortex shapes functional connectivity on multiple time scales

    Science.gov (United States)

    Honey, Christopher J.; Kötter, Rolf; Breakspear, Michael; Sporns, Olaf

    2007-01-01

    Neuronal dynamics unfolding within the cerebral cortex exhibit complex spatial and temporal patterns even in the absence of external input. Here we use a computational approach in an attempt to relate these features of spontaneous cortical dynamics to the underlying anatomical connectivity. Simulating nonlinear neuronal dynamics on a network that captures the large-scale interregional connections of macaque neocortex, and applying information theoretic measures to identify functional networks, we find structure–function relations at multiple temporal scales. Functional networks recovered from long windows of neural activity (minutes) largely overlap with the underlying structural network. As a result, hubs in these long-run functional networks correspond to structural hubs. In contrast, significant fluctuations in functional topology are observed across the sequence of networks recovered from consecutive shorter (seconds) time windows. The functional centrality of individual nodes varies across time as interregional couplings shift. Furthermore, the transient couplings between brain regions are coordinated in a manner that reveals the existence of two anticorrelated clusters. These clusters are linked by prefrontal and parietal regions that are hub nodes in the underlying structural network. At an even faster time scale (hundreds of milliseconds) we detect individual episodes of interregional phase-locking and find that slow variations in the statistics of these transient episodes, contingent on the underlying anatomical structure, produce the transfer entropy functional connectivity and simulated blood oxygenation level-dependent correlation patterns observed on slower time scales. PMID:17548818

  6. 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.

  7. 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.

  8. 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

  9. 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.

  10. 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...... two different sets of interneurons. Our data imply that for a given cortical area the amplitude of vascular signals will depend critically on the type of input and hence on the type of neurons activated. In the second study I investigated the effect of cortical spreading depression (CSD) on the evoked...... 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...

  11. A concussive-like brain injury model in mice (II): selective neuronal loss in the cortex and hippocampus.

    Science.gov (United States)

    Tang, Y P; Noda, Y; Hasegawa, T; Nabeshima, T

    1997-11-01

    A novel concussive-like brain injury (CLBI) model characterized by transient neurobehavioral depression, short duration of brain edema, and long-lasting memory deficits has been reported in our companion paper. This was achieved by dropping a 21-g weight from a height of 25 cm onto the head of a mouse. In the present study, we examined the histopathological changes in this model. Male ddY mice were subjected to either the trauma or sham injury. Gross pathological examination of the brain 1 h posttrauma did not demonstrate subdural, subarachnoid, intraventricular, periventricular, and intraparenchymatous hemorrhage, focal lesions or contusions. Microscopic examination 24 h posttrauma with Nissl staining (cresyl violet), however, revealed a selective bilateral neuronal cell loss in the cerebral cortex and hippocampus but not in the regions of the thalamus, cerebellum, and brain stem. The characteristics of neuronal cell loss in the cortex suggested that this pathology was related in part, to the head impact dynamics, since the cell loss was noted in the central portion of the supraventricular cerebral cortex (p < 0.001), the site of the weight impact, gradually decreasing peripheral to this site, and disappearing in the areas remote from this locus. In contrast, neuronal cell loss seen in the hippocampus did not suggest that this pathology was directly associated with the impact site. Neuronal cell loss was concentrated in the pyramidal cell layer of CA2 (p < 0.01) and CA3 (p < 0.01), and a lesser degree was noted in the subfields of CA3c (p < 0.05) and the hilar region (p < 0.05) but not in the subfields of CA1 and the dentate gyrus layers. The present study characterized the histopathological change seen in the CLBI model, demonstrating the selective neuronal cell loss following weight-drop concussion in mice. PMID:9421457

  12. Swainsonine-induced apoptosis pathway in cerebral cortical neurons.

    Science.gov (United States)

    Lu, Hao; Ma, Feng; Zhang, Liang; Wang, Jianguo; Wu, Chenchen; Zhao, Baoyu

    2015-10-01

    Swainsonine (SW) is an indolizidine alkaloid, and the principal toxic component of the poisonous legume plants Astragalus and Oxytropis sp. Animals that consume the toxic plants show neurologic symptoms. In this study, the cerebral cortical neurons of primary culture were treated for 12h with various concentrations of SW. The [Ca(2+)]i and the protein expression of caspase-3, -8, -9 and -12 were assessed in all experimental groups. In comparison with the control group, [Ca(2+)]i increased significantly in SW-treated groups (P0.05). The results suggest that SW induced the apoptosis of neurons through a death receptor pathway and endoplasmic reticulum stress. PMID:26412516

  13. Contribution of oxygen-sensitive neurons of the rostral ventrolateral medulla to hypoxic cerebral vasodilatation in the rat

    Science.gov (United States)

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

    1996-01-01

    1. We sought to determine whether hypoxic stimulation of neurons of the rostral ventrolateral reticular nucleus (RVL) would elevate regional cerebral blood flow (rCBF) in anaesthetized paralysed rats. 2. Microinjection of sodium cyanide (NaCN; 150-450 pmol) into the RVL rapidly (within 1-2 s), transiently, dose-dependently and site-specifically elevated rCBF1 measured by laser Doppler flowmetry, by 61.3 +/- 22.1% (P anaesthesia. 4. Electrical stimulation of NaCN-sensitive sites in the RVL in spinalized rats increased rCBF measured autoradiographically with 14C iodoantipyrine (Kety method) in the mid-line thalamus (by 182.3 +/- 17.2%; P < 0.05) and cerebral cortex (by 172.6 +/- 15.6%; P < 0.05) regions, respectively, directly or indirectly innervated by RVL neurons, and in the remainder of the brain. In contrast regional cerebral glucose utilization (rCGU), measured autoradiographically with 14C-2-deoxyglucose (Sokoloff method), was increased in proportion to rCBF in the mid-line thalamus (165.6 +/- 17.8%, P < 0.05) but was unchanged in the cortex. 5. Bilateral electrolytic lesions of NaCN sensitive sites of RVL, while not altering resting rCBF or the elevation elicited by hypercarbia (arterial CO2 pressure, Pa,CO2, approximately 69 mmHg), reduced the vasodilatation elicited by normocapnic hypoxaemia (arterial O2 pressure, Pa,O2, approximately 27 mmHg) by 67% (P < 0.01) and flattened the slope of the Pa,O2-rCBF response curve. 6. We conclude that the elevation of rCBF produced in the cerebral cortex by hypoxaemia is in large measure neurogenic, mediated trans-synaptically over intrinsic neuronal pathways, and initiated by excitation of oxygen sensitive neurons in the RVL.

  14. Glutamate-induced activation of nitric oxide synthase is impaired in cerebral cortex in vivo in rats with chronic liver failure.

    Science.gov (United States)

    Rodrigo, Regina; Erceg, Slaven; Rodriguez-Diaz, Jesus; Saez-Valero, Javier; Piedrafita, Blanca; Suarez, Isabel; Felipo, Vicente

    2007-07-01

    It has been proposed that impairment of the glutamate-nitric oxide-cyclic guanosine monophosphate (cGMP) pathway in brain contributes to cognitive impairment in hepatic encephalopathy. The aims of this work were to assess whether the function of this pathway and of nitric oxide synthase (NOS) are altered in cerebral cortex in vivo in rats with chronic liver failure due to portacaval shunt (PCS) and whether these alterations are due to hyperammonemia. The glutamate-nitric oxide-cGMP pathway function and NOS activation by NMDA was analysed by in vivo microdialysis in cerebral cortex of PCS and control rats and in rats with hyperammonemia without liver failure. Similar studies were done in cortical slices from these rats and in cultured cortical neurons exposed to ammonia. Basal NOS activity, nitrites and cGMP are increased in cortex of rats with hyperammonemia or liver failure. These increases seem due to increased inducible nitric oxide synthase expression. NOS activation by NMDA is impaired in cerebral cortex in both animal models and in neurons exposed to ammonia. Chronic liver failure increases basal NOS activity, nitric oxide and cGMP but reduces activation of NOS induced by NMDA receptors activation. Hyperammonemia is responsible for both effects which will lead, independently, to alterations contributing to neurological alterations in hepatic encephalopathy. PMID:17286583

  15. 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.

  16. Toxic effect of aflatoxin B1 and the role of recovery on the rat cerebral cortex and hippocampus.

    Science.gov (United States)

    Bahey, Noha Gamal; Abd Elaziz, Hekmat Osman; Gadalla, Kamal Kamal El Sayed

    2015-12-01

    Aflatoxin B1 (AFB1) is the most toxic and well-known mycotoxin that exists in many food stuff. Exposure to AFB1 has been reported to produce serious biochemical and structural alterations in human and animal organs, however, its effect on the brain is not well studied. Therefore, this study was aimed to investigate the possible histopathological effect of AFB1 and its withdrawal on the cerebral cortex and hippocampus. Fifteen adult female Wistar rats were divided into 3 equal groups: control, AFB1 (15.75 μg/kg/orally, once weekly, for 8 weeks) and recovery groups. Brain sections were processed for hematoxylin and eosin staining as well as for NeuN and GFAP immunostaining. AFB1 administration resulted in several histopathological alterations including; cellular degeneration, dilatation of the blood vessels and significant decrease in the thickness of the frontal cortex and the hippocampal CA1 pyramidal cell layer. In the frontal cortex, there was a significant reduction in the percentage of astrocyte distribution without changes in neuronal numbers. On the other hand, in the hippocampal CA1 region, there was a significant reduction of neuronal number and a significant increase in the percentage of astrocyte distribution. Importantly, AFB1-induced structural alterations were rescued following AFB1 withdrawal. In conclusion, AFB1 induce histological alterations in the rat brain which are potentially reversible upon withdrawal. PMID:26380901

  17. 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.

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

    Science.gov (United States)

    Winter, Mark R; Liu, Mo; Monteleone, David; Melunis, Justin; Hershberg, Uri; Goderie, Susan K; Temple, Sally; Cohen, Andrew R

    2015-10-13

    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. PMID:26344906

  19. 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...

  20. Local Circuit Inhibition in the Cerebral Cortex as the source of Gain Control and Untuned Suppression

    OpenAIRE

    Shapley, Robert M.; Xing, Dajun

    2012-01-01

    Theoretical considerations have led to the concept that the cerebral cortex is operating in a balanced state in which synaptic excitation is approximately balanced by synaptic inhibition from the local cortical circuit. This paper is about the functional consequences of the balanced state in sensory cortex. One consequence is gain control: there is experimental evidence and theoretical support for the idea that local circuit inhibition acts as a local automatic gain control throughout the cor...

  1. Human Development XI: The Structure of the Cerebral Cortex. Are There Really Modules in the Brain?

    OpenAIRE

    Tyge Dahl Hermansen; Søren Ventegodt; Isack Kandel

    2007-01-01

    The structure of human consciousness is thought to be closely connected to the structure of cerebral cortex. One of the most appreciated concepts in this regard is the Szanthagothei model of a modular building of neo-cortex. The modules are believed to organize brain activity pretty much like a computer. We looked at examples in the literature and argue that there is no significant evidence that supports Szanthagothei's model. We discuss the use of the limited genetic information, the cortico...

  2. Handedness Is Associated with Asymmetries in Gyrification of the Cerebral Cortex of Chimpanzees

    OpenAIRE

    Hopkins, William D.; Cantalupo, Claudio; Taglialatela, Jared

    2006-01-01

    Gyrification of the cerebral cortex reflects complexity in cortical folding during development of the brain. In this paper, we evaluated whether chimpanzees show asymmetries in gyrification and if variation in gyrification asymmetries were associated with handedness. Magnetic resonance images were obtained in a sample of 76 chimpanzees, and gyrification measures were obtained from 10 equally spaced slices of the cortex. Asymmetry quotients (AQs) in gyrification were compared for 4 measures of...

  3. 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

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

    OpenAIRE

    Bob Jacobs; Busisiwe C Maseko; Albert Lewandowski; Mary Ann Raghanti; Bridget Wicinski; William Hopkins; Bertelsen, Mads F; Timothy Walsh; Roger Reep; Sherwood, Chet C.

    2014-01-01

    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, clo...

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

    OpenAIRE

    Jacobs, Bob; Johnson, Nicholas L.; Wahl, Devin; Schall, Matthew; Busisiwe C Maseko; Lewandowski, Albert; Raghanti, Mary A.; Wicinski, Bridget; Butti, Camilla; Hopkins, William D.; Bertelsen, Mads F; Walsh, Timothy; Roberts, John R.; Reep, Roger L.; Hof, Patrick R

    2014-01-01

    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, clou...

  6. 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.

  7. 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...

  8. 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.

  9. Effect of hyperbaric oxygenation on mitochondrial function of neuronal cells in the cortex of neonatal rats after hypoxic-ischemic brain damage

    OpenAIRE

    Yang, L.; Hei, M.Y.; Dai, J.J.; Hu, N.; Xiang, X.Y.

    2016-01-01

    The timing and mechanisms of protection by hyperbaric oxygenation (HBO) in hypoxic-ischemic brain damage (HIBD) have only been partially elucidated. We monitored the effect of HBO on the mitochondrial function of neuronal cells in the cerebral cortex of neonatal rats after HIBD. Neonatal Sprague-Dawley rats (total of 360 of both genders) were randomly divided into normal control, HIBD, and HIBD+HBO groups. The HBO treatment began immediately after hypoxia-ischemia (HI) and continued once a da...

  10. Fluoxetine (prozac) and serotonin act on excitatory synaptic transmission to suppress single layer 2/3 pyramidal neuron-triggered cell assemblies in the human prefrontal cortex.

    OpenAIRE

    Komlosi, G.; Molnar, G.; Rozsa, M.; Olah, S.; Barzo, P.; Tamas, G.

    2012-01-01

    Selective serotonin reuptake inhibitors are the most widely prescribed drugs targeting the CNS with acute and chronic effects in cognitive, emotional and behavioral processes. This suggests that microcircuits of the human cerebral cortex are powerfully modulated by selective serotonin reuptake inhibitors, however, direct measurements of serotonergic regulation on human synaptic interactions are missing. Using multiple whole-cell patch-clamp recordings from neurons in acute cortical slices der...

  11. 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.

  12. 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.

  13. 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...

  14. Importance of Reelin C-terminal region in the development and maintenance of the postnatal cerebral cortex and its regulation by specific proteolysis

    DEFF Research Database (Denmark)

    Kohno, Takao; Honda, Takao; Kubo, Ken-Ichiro;

    2015-01-01

    strength, is increased in the KI mouse, indicating that the CTR is necessary for efficient induction of Dab1 phosphorylation in vivo. Formation of layer structures during embryonic development is normal in the KI mouse. Intriguingly, the marginal zone (MZ) of the cerebral cortex becomes narrower at......, which is not required for neuronal migration during embryonic stages but is required for the development and maintenance of the MZ in the postnatal cerebral cortex.......During brain development, Reelin exerts a variety of effects in a context-dependent manner, whereas its underlying molecular mechanisms remain poorly understood. We previously showed that the C-terminal region (CTR) of Reelin is required for efficient induction of phosphorylation of Dab1, an...

  15. 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.

  16. 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.

  17. 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.

  18. 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

  19. 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)

  20. 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

  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. 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...

  3. 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...

  4. 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...... of the astrocyte marker proteins. The metabolic pattern of the cultures from 7-day-old animals of the labeled substrates was comparable to that seen previously in astrocyte cultures prepared from new-born mouse brain showing pronounced glycolytic and oxidative metabolism of glucose. Glutamate was...... prepared from cerebral cortex of 7-day-old mice have metabolic and functional properties indistinguishable from those of classical astrocyte cultures prepared from neocortex of new-born animals. This provides flexibility with regard to preparation and use of these cultures for a variety of purposes....

  5. 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.

  6. Different effects of transcutaneous electric nerve stimulation and electroacupuncture at ST36–ST37 on the cerebral cortex

    OpenAIRE

    Kang, Yu-Tien; Liao, Yi-Sheng; Hsieh, Ching-Liang

    2014-01-01

    Background The effects of transcutaneous electric nerve stimulation (TENS) and electroacupuncture (EA) on the cerebral cortex are largely unclear. The purpose of the present study was to investigate the effect of TENS and EA on the cerebral cortex by examining their effect on the median nerve-somatosensory evoked potentials (MN-SEPs). Methods Twenty volunteers were studied. The cortical and cervical spinal potentials were recorded by median nerve stimulation at the left wrist. Sham TENS, 2 Hz...

  7. Adenomatous polyposis coli is required for early events in the normal growth and differentiation of the developing cerebral cortex

    OpenAIRE

    Price David J; Mason John O; Chen Yijing; Ivaniutsin Uladzislau; Pratt Thomas

    2009-01-01

    Abstract Background Adenomatous polyposis coli (Apc) is a large multifunctional protein known to be important for Wnt/β-catenin signalling, cytoskeletal dynamics, and cell polarity. In the developing cerebral cortex, Apc is expressed in proliferating cells and its expression increases as cells migrate to the cortical plate. We examined the consequences of loss of Apc function for the early development of the cerebral cortex. Results We used Emx1Cre to inactivate Apc specifically in proliferat...

  8. Adenomatous polyposis coli is required for early events in the normal growth and differentiation of the developing cerebral cortex

    OpenAIRE

    Ivaniutsin, Uladzislau; CHEN, Yijing; John O. MASON; Price, David; Pratt, Thomas

    2009-01-01

    Background: Adenomatous polyposis coli (Apc) is a large multifunctional protein known to be important for Wnt/beta-catenin signalling, cytoskeletal dynamics, and cell polarity. In the developing cerebral cortex, Apc is expressed in proliferating cells and its expression increases as cells migrate to the cortical plate. We examined the consequences of loss of Apc function for the early development of the cerebral cortex.Results: We used Emx1(Cre) to inactivate Apc specifically in proliferating...

  9. 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.

  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. 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...

  12. The effects of p-chloromercuribenzoate on muscarinic receptors in the cerebral cortex.

    OpenAIRE

    Birdsall, N. J.; Burgen, A S; Hulme, E. C.; Wong, E. H.

    1983-01-01

    The action of p-chloromercuribenzoate (PCMB) on the ligand binding properties of the muscarinic receptors in the rat cerebral cortex has been examined. At low concentrations, PCMB produces a selective change in the binding of agonists without any effect on the binding of antagonists. At higher concentrations, the structure-binding profile for binding antagonists is changed. The affinity of agonists is greatly reduced and the heterogeneity of binding eliminated. The effects of both high and lo...

  13. 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 ...

  14. Mitochondrial complex I inhibition in cerebral cortex of immature rats following homocysteic acid-induced seizures

    Czech Academy of Sciences Publication Activity Database

    Folbergrová, Jaroslava; Ješina, Pavel; Drahota, Zdeněk; Lisý, Václav; Haugvicová, Renata; Vojtíšková, Alena; Houštěk, Josef

    2007-01-01

    Roč. 204, č. 2 (2007), s. 597-609. ISSN 0014-4886 R&D Projects: GA ČR(CZ) GA309/05/2015; GA ČR(CZ) GA303/06/1261; GA MŠk 1M0520 Institutional research plan: CEZ:AV0Z50110509; CEZ:AV0Z50200510 Keywords : cerebral cortex * homocysteic acid * free radical scavenger Subject RIV: ED - Physiology Impact factor: 3.982, year: 2007

  15. Dynamic Gene Expression in the Human Cerebral Cortex Distinguishes Children from Adults

    OpenAIRE

    Sterner, Kirstin N.; Weckle, Amy; Chugani, Harry T.; Tarca, Adi L.; Sherwood, Chet C.; Hof, Patrick R; Kuzawa, Christopher W.; Boddy, Amy M.; Abbas, Asad; Raaum, Ryan L.; Grégoire, Lucie; Lipovich, Leonard; Grossman, Lawrence I; Uddin, Monica; Goodman, Morris

    2012-01-01

    In comparison with other primate species, humans have an extended juvenile period during which the brain is more plastic. In the current study we sought to examine gene expression in the cerebral cortex during development in the context of this adaptive plasticity. We introduce an approach designed to discriminate genes with variable as opposed to uniform patterns of gene expression and found that greater inter-individual variance is observed among children than among adults. For the 337 tran...

  16. 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...

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

    DEFF Research Database (Denmark)

    Dreier, Jens P; Major, Sebastian; Pannek, Heinz-Wolfgang;

    2012-01-01

    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...

  18. 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

  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. 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

  1. 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 ...

  2. GABA-Synthesizing Enzymes in Calbindin and Calretinin Neurons in Monkey Prefrontal Cortex.

    Science.gov (United States)

    Rocco, Brad R; Sweet, Robert A; Lewis, David A; Fish, Kenneth N

    2016-05-01

    Non-overlapping groups of cortical γ-aminobutyric acid-releasing (GABAergic) neurons are identifiable by the presence of calbindin (CB), calretinin (CR), or parvalbumin (PV). Boutons from PV neuron subtypes are also distinguishable by differences in protein levels of the GABA-synthesizing enzymes GAD65 and GAD67. Multilabel fluorescence microscopy was used to determine if this diversity extends to boutons of CB and CR neurons in monkey prefrontal cortex. CB and CR neurons gave rise to 3 subpopulations of GAD-containing boutons: GAD65+, GAD67+, and GAD65/GAD67+. Somatostatin and vasoactive intestinal peptide-expressing neurons, subtypes of CB and CR neurons, respectively, also gave rise to these distinct bouton subpopulations. At the transcript level, CB and CR neurons contained mRNA encoding GAD67-only or both GADs. Thus, the distinct subpopulations of CB/GAD+ and CR/GAD+ boutons arise from 2 unique subtypes of CB and CR neurons. The different CB and CR GAD-expressing neurons targeted the same projection neurons and neuronal structures immunoreactive for PV, CR, or CB. These findings suggest that GABA synthesis from CB/GAD67+ and CR/GAD67+ neurons would presumably be more vulnerable to disease-associated deficits in GAD67 expression, such as in schizophrenia, than neurons that also contain GAD65. PMID:25824535

  3. Local-Circuit Phenotypes of Layer 5 Neurons in Motor-Frontal Cortex of YFP-H Mice

    OpenAIRE

    Sheets, Patrick L; Shepherd, Gordon M. G.

    2008-01-01

    Layer 5 pyramidal neurons comprise an important but heterogeneous group of cortical projection neurons. In motor-frontal cortex, these neurons are centrally involved in the cortical control of movement. Recent studies indicate that local excitatory networks in mouse motor-frontal cortex are dominated by descending pathways from layer 2/3 to 5. However, those pathways were identified in experiments involving unlabeled neurons in wild type mice. Here, to explore the possibility of class-specifi...

  4. 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...

  5. 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.

  6. 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

  7. Neuroprotection via matrix-trophic coupling between cerebral endothelial cells and neurons

    OpenAIRE

    Guo, Shuzhen; Kim, Woo Jean; Lok, Josephine; Lee, Sun-Ryung; Besancon, Elaine; Luo, Bing-Hao; Stins, Monique F.; Wang, Xiaoying; Dedhar, Shoukat; Lo, Eng H.

    2008-01-01

    The neurovascular unit is an emerging concept that emphasizes homeostatic interactions between endothelium and cerebral parenchyma. Here, we show that cerebral endothelium are not just inert tubes for delivering blood, but they also secrete trophic factors that can be directly neuroprotective. Conditioned media from cerebral endothelial cells broadly protects neurons against oxygen-glucose deprivation, oxidative damage, endoplasmic reticulum stress, hypoxia, and amyloid neurotoxicity. This ph...

  8. Close temporal coupling of neuronal activity and tissue oxygen responses in rodent whisker barrel cortex

    OpenAIRE

    Li, Jennifer; Bravo, Diego S.; Upton, A. Louise; Gilmour, Gary; Tricklebank, Mark; Fillenz, Marianne; Martin, Chris; Lowry, John P.; Bannerman, David M.; McHugh, Stephen B.

    2011-01-01

    Neuronal activity elicits metabolic and vascular responses, during which oxygen is first consumed and then supplied to the tissue via an increase in cerebral blood flow. Understanding the spatial and temporal dynamics of blood and tissue oxygen (To2 ) responses following neuronal activity is crucial for understanding the physiological basis of functional neuroimaging signals. However, our knowledge is limited because previous To2 measurements have been made at low temporal resolution...

  9. 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.

  10. Adenomatous polyposis coli is required for early events in the normal growth and differentiation of the developing cerebral cortex

    Directory of Open Access Journals (Sweden)

    Price David J

    2009-01-01

    Full Text Available Abstract Background Adenomatous polyposis coli (Apc is a large multifunctional protein known to be important for Wnt/β-catenin signalling, cytoskeletal dynamics, and cell polarity. In the developing cerebral cortex, Apc is expressed in proliferating cells and its expression increases as cells migrate to the cortical plate. We examined the consequences of loss of Apc function for the early development of the cerebral cortex. Results We used Emx1Cre to inactivate Apc specifically in proliferating cerebral cortical cells and their descendents starting from embryonic day 9.5. We observed reduction in the size of the mutant cerebral cortex, disruption to its organisation, and changes in the molecular identity of its cells. Loss of Apc leads to a decrease in the size of the proliferative pool, disrupted interkinetic nuclear migration, and increased apoptosis. β-Catenin, pericentrin, and N-cadherin proteins no longer adopt their normal high concentration at the apical surface of the cerebral cortical ventricular zone, indicating that cell polarity is disrupted. Consistent with enhanced Wnt/β-catenin signalling resulting from loss of Apc we found increased levels of TCF/LEF-dependent transcription and expression of endogenous Wnt/β-catenin target genes (Axin2 (conductin, Lef1, and c-myc in the mutant cerebral cortex. In the Apc mutant cerebral cortex the expression of transcription factors Foxg1, Pax6, Tbr1, and Tbr2 is drastically reduced compared to normal and many cells ectopically express Pax3, Wnt1, and Wt1 (but not Wnt2b, Wnt8b, Ptc, Gli1, Mash1, Olig2, or Islet1. This indicates that loss of Apc function causes cerebral cortical cells to lose their normal identity and redirect to fates normally found in more posterior-dorsal regions of the central nervous system. Conclusion Apc is required for multiple aspects of early cerebral cortical development, including the regulation of cell number, interkinetic nuclear migration, cell polarity, and

  11. 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

  12. 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...

  13. 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...

  14. 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)...

  15. 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...

  16. 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

  17. 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

  18. 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.

  19. 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.

  20. 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

  1. 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

  2. Atorvastatin withdrawal elicits oxidative/nitrosative damage in the rat cerebral cortex.

    Science.gov (United States)

    de Oliveira, Clarissa Vasconcelos; Funck, Vinícius Rafael; Pereira, Letícia Meier; Grigoletto, Jéssica; Rambo, Leonardo Magno; Ribeiro, Leandro Rodrigo; Royes, Luiz Fernando Freire; Furian, Ana Flávia; Oliveira, Mauro Schneider

    2013-05-01

    Statins are inhibitors of the enzyme 3-hydroxy-3-methylglutaryl coenzyme A reductase, the rate-limiting step in cholesterol biosynthesis. Statins effectively prevent and reduce the risk of coronary artery disease through lowering serum cholesterol, and also exert anti-thrombotic, anti-inflammatory and antioxidant effects independently of changes in cholesterol levels. On the other hand, clinical and experimental evidence suggests that abrupt cessation of statin treatment (i.e. statin withdrawal) is associated with a deleterious rebound phenomenon. In fact, statin withdrawal increases the risk of thrombotic vascular events, causes impairment of endothelium-dependent relaxation and facilitates experimental seizures. However, evidence for statin withdrawal-induced detrimental effects to the brain parenchyma is still lacking. In the present study adult male Wistar rats were treated with atorvastatin for seven days (10mg/kg/day) and neurochemical assays were performed in the cerebral cortex 30 min (atorvastatin treatment) or 24h (atorvastatin withdrawal) after the last atorvastatin administration. We found that atorvastatin withdrawal decreased levels of nitric oxide and mitochondrial superoxide dismutase activity, whereas increased NADPH oxidase activity and immunoreactivity for the protein nitration marker 3-nitrotyrosine in the cerebral cortex. Catalase, glutathione-S-transferase and xanthine oxidase activities were not altered by atorvastatin treatment or withdrawal, as well as protein carbonyl and 4-hydroxy-2-nonenal immunoreactivity. Immunoprecipitation of mitochondrial SOD followed by analysis of 3-nitrotyrosine revealed increased levels of nitrated mitochondrial SOD, suggesting the mechanism underlying the atorvastatin withdrawal-induced decrease in enzyme activity. Altogether, our results indicate the atorvastatin withdrawal elicits oxidative/nitrosative damage in the rat cerebral cortex, and that changes in NADPH oxidase activity and mitochondrial superoxide

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

    Directory of Open Access Journals (Sweden)

    Bob Jacobs

    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.

  4. Effect of β-endorphin on catecholamine levels in rat hypothalamus and cerebral cortex

    International Nuclear Information System (INIS)

    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

  5. 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.

  6. Kinetic evidence suggesting two mechanisms for iodothyronine 5'-deiodination in rat cerebral cortex.

    OpenAIRE

    Visser, T J; Leonard, J L; Kaplan, M. M.; Larsen, P R

    1982-01-01

    Enzymatic 5'-deiodination of 3,3',5'-triiodothyronine (rT3) and 3,3',5,5'-tetraiodothyronine (thyroxine, T4) was studied in microsomal preparations of rat cerebral cortex. Evidence was obtained for the existence of two thiol-dependent 5'-deiodinase entities. One of these predominates in tissue from euthyroid and long-term hypothyroid rats, is specific for rT3, follows "ping-pong" kinetics with dithiothreitol as the cosubstrate, and is inhibited by propylthiouracil (PrSUra) and iodoacetate. In...

  7. 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.

  8. 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 ...

  9. Traversing Scales: Large Scale Simulation of the Cat Cortex Using Single Neuron Models

    Czech Academy of Sciences Publication Activity Database

    Vejmelka, Martin; Fründ, I.; Pillai, A.

    Berlin: Springer-Verlag, 2008 - (Graben, P.; Zhou, C.; Thiel, M.; Kurths, J.), s. 331-342. (Understanding Complex Systems). ISBN 978-3-540-73158-0 Institutional research plan: CEZ:AV0Z10300504 Keywords : cat cortex * large scale simulation * single neuron models * spiking models * complex networks * neural connectivity * signal propagation Subject RIV: IN - Informatics, Computer Science

  10. 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

  11. 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...

  12. 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...

  13. 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.

  14. Direct neuronal glucose uptake Heralds activity-dependent increases in cerebral metabolism

    DEFF Research Database (Denmark)

    Lundgaard, Iben; Li, Baoman; Xie, Lulu; Kang, Hongyi; Sanggaard, Simon; Haswell, John D R; Sun, Wei; Goldman, Siri; Blekot, Solomiya; Nielsen, Michael; Takano, Takahiro; Deane, Rashid; Nedergaard, Maiken

    2015-01-01

    Metabolically, the brain is a highly active organ that relies almost exclusively on glucose as its energy source. According to the astrocyte-to-neuron lactate shuttle hypothesis, glucose is taken up by astrocytes and converted to lactate, which is then oxidized by neurons. Here we show, using two......, hexokinase, which catalyses the first enzymatic steps in glycolysis, was highly enriched in neurons compared with astrocytes, in mouse as well as in human cortex. These observations suggest that brain activity and neuronal glucose metabolism are directly linked, and identify the neuron as the principal locus...

  15. 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.

  16. 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

  17. Branching patterns for arterioles and venules of the human cerebral cortex.

    Science.gov (United States)

    Cassot, Francis; Lauwers, Frederic; Lorthois, Sylvie; Puwanarajah, Prasanna; Cances-Lauwers, Valérie; Duvernoy, Henri

    2010-02-01

    Branching patterns of microvascular networks influence vascular resistance and allow control of peripheral flow distribution. The aim of this paper was to analyze these branching patterns in human cerebral cortex. Digital three-dimensional images of the microvascular network were obtained from thick sections of India ink-injected human brain by confocal laser microscopy covering a large zone of secondary cortex. A novel segmentation method was used to extract the skeletons of 228 vascular trees (152 arterioles and 76 venules) and measure the diameter at every vertex. The branching patterns (area ratios and angles of bifurcations) of nearly 10,000 bifurcations of cortical vascular trees were analyzed, establishing their statistical properties and structural variations as a function of the vessel nature (arterioles versus venules), the parent vessel topological order or the bifurcation type. We also describe their connectivity and discuss the relevance of the assumed optimal design of vascular branching to account for the complex nature of microvascular architecture. The functional implications of some of these structural variations are considered. The branching patterns established from a large database of a human organ contributes to a better understanding of the bifurcation design and provides an essential reference both for diagnosis and for a future large reconstruction of cerebral microvascular network. PMID:20005216

  18. Quinolinic acid effects on amino acid release from the rat cerebral cortex in vitro and in vivo.

    OpenAIRE

    Connick, J. H.; Stone, T. W.

    1988-01-01

    1. The effect of quinolinic acid, N-methyl-D,L-aspartate (NMDLA) and kainate on the release of endogenous and exogenous amino acids from the rat cerebral cortex in vitro and in vivo was studied. 2. Neither quinolinic acid nor NMDLA had any effect on the basal or potassium-evoked release of [3H]-D-aspartate from slices of rat cerebral cortex either in the presence or absence of magnesium. Kainic acid failed to modify the basal efflux of [3H]-D-aspartate but significantly inhibited (by 34.4% +/...

  19. 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...

  20. Protective effects of quercetine on the neuronal injury in frontal cortex after chronic toluene exposure.

    Science.gov (United States)

    Kanter, Mehmet

    2013-08-01

    The aim of this study was designed to evaluate the possible protective effects of quercetine (QE) on the neuronal injury in the frontal cortex after chronic toluene exposure in rats. The rats were randomly allotted into one of the three experimental groups, namely, groups A (control), B (toluene treated) and C (toluene-treated with QE), where each group contains 10 animals. Control group received 1 ml of normal saline solution, and toluene treatment was performed by the inhalation of 3000 ppm toluene in an 8-h/day and 6-day/week order for 12 weeks. The rats in QE-treated group was given QE (15 mg/kg body weight) once a day intraperitoneally for 12 weeks, starting just after toluene exposure. Tissue samples were obtained for histopathological investigation. To date, no histopathological changes of neurodegeneration in the frontal cortex after chronic toluene exposure in rats by QE treatment have been reported. In this study, the morphology of neurons in the QE treatment group was well protected. Chronic toluene exposure caused severe degenerative changes, shrunken cytoplasm and extensively dark picnotic nuclei in neurons of the frontal cortex. We conclude that QE therapy causes morphologic improvement in neurodegeneration of frontal cortex after chronic toluene exposure in rats. We believe that further preclinical research into the utility of QE may indicate its usefulness as a potential treatment on neurodegeneration after chronic toluene exposure in rats. PMID:22252859

  1. 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.

  2. 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.

  3. 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.

  4. 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; Sampson, Allan R.; Lewis, David A.

    2007-01-01

    A number of studies that assessed the visual system in subjects with schizophrenia found impairments in early visual processing. Furthermore, functional imaging studies suggested changes in primary visual cortex activity in subjects with schizophrenia. Interestingly, postmortem studies of subjects...... 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...... have a smaller cortical area allocated to primary visual perception. This finding suggests the existence of a schizophrenia-related change in cortical parcellation...

  5. 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

  6. How does transcranial DC stimulation of the primary motor cortex alter regional neuronal activity in the human brain?

    Science.gov (United States)

    Lang, Nicolas; Siebner, Hartwig R; Ward, Nick S; Lee, Lucy; Nitsche, Michael A; Paulus, Walter; Rothwell, John C; Lemon, Roger N; Frackowiak, Richard S

    2005-07-01

    Transcranial direct current stimulation (tDCS) of the primary motor hand area (M1) can produce lasting polarity-specific effects on corticospinal excitability and motor learning in humans. In 16 healthy volunteers, O positron emission tomography (PET) of regional cerebral blood flow (rCBF) at rest and during finger movements was used to map lasting changes in regional synaptic activity following 10 min of tDCS (+/-1 mA). Bipolar tDCS was given through electrodes placed over the left M1 and right frontopolar cortex. Eight subjects received anodal or cathodal tDCS of the left M1, respectively. When compared to sham tDCS, anodal and cathodal tDCS induced widespread increases and decreases in rCBF in cortical and subcortical areas. These changes in rCBF were of the same magnitude as task-related rCBF changes during finger movements and remained stable throughout the 50-min period of PET scanning. Relative increases in rCBF after real tDCS compared to sham tDCS were found in the left M1, right frontal pole, right primary sensorimotor cortex and posterior brain regions irrespective of polarity. With the exception of some posterior and ventral areas, anodal tDCS increased rCBF in many cortical and subcortical regions compared to cathodal tDCS. Only the left dorsal premotor cortex demonstrated an increase in movement related activity after cathodal tDCS, however, modest compared with the relatively strong movement-independent effects of tDCS. Otherwise, movement related activity was unaffected by tDCS. Our results indicate that tDCS is an effective means of provoking sustained and widespread changes in regional neuronal activity. The extensive spatial and temporal effects of tDCS need to be taken into account when tDCS is used to modify brain function. PMID:16045502

  7. Changing microcircuits in the subplate of the developing cortex

    OpenAIRE

    Viswanathan, Sarada; Bandyopadhyay, Sharba; Kao, Joseph P.Y.; Kanold, Patrick O.

    2012-01-01

    Subplate neurons (SPNs) are a population of neurons in the mammalian cerebral cortex that exist predominantly in the prenatal and early postnatal period. Loss of SPNs prevents the functional maturation of the cerebral cortex. SPNs receive subcortical input from the thalamus and relay this information to the developing cortical plate and thereby can influence cortical activity in a feed-forward manner. Little is known about potential feedback projections from the cortical plate to SPNs. Thus, ...

  8. Functional diversity of supragranular GABAergic neurons in the barrel cortex

    Directory of Open Access Journals (Sweden)

    Luc J Gentet

    2012-08-01

    However, recent technological advances in microscopy and mouse genetics have fostered a renewed interest in neocortical interneurons by putting them within “visible” reach of experimenters. The anatomically well-defined whisker-to-barrel pathway of the rodent is particularly amenable to studies attempting to link cortical circuit dynamics to behavior. To each whisker corresponds a discrete cortical unit equivalent to a single column, specialized in the encoding and processing of the sensory information it receives. In this review, we will focus on the functional role that each subtype of supragranular GABAergic neuron embedded within such a single neocortical unit may play in shaping the dynamics of the local circuit during somatosensory integration.

  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. 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...

  11. Cytoplasmic and nuclear estradiol receptors in the hypothalamus and cerebral cortex of female rats during the neonatal period

    International Nuclear Information System (INIS)

    The content of estradifol receptors (E2) in the cytoplasmic and nuclear fractions of the hypothalamus and cerebral cortex of female rats was investigated in the course of neonatal development. In the cytosol of the hypothalamus and cortex, the E2-binding proteins, which possess high capacity, include both the true estradiol receptors and proteins identical with α-fetoprotein. True receptors E2 were detected in the nuclear fraction; in the hypothalamus their concentration was virtually unchanged, while in the cortex it decreased from the first to fifth days of postnatal development

  12. 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; Savaran, V; Zagrean, L

    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....

  13. 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

  14. Spatial structure of neuronal receptive field in awake monkey secondary visual cortex (V2).

    Science.gov (United States)

    Liu, Lu; She, Liang; Chen, Ming; Liu, Tianyi; Lu, Haidong D; Dan, Yang; Poo, Mu-ming

    2016-02-16

    Visual processing depends critically on the receptive field (RF) properties of visual neurons. However, comprehensive characterization of RFs beyond the primary visual cortex (V1) remains a challenge. Here we report fine RF structures in secondary visual cortex (V2) of awake macaque monkeys, identified through a projection pursuit regression analysis of neuronal responses to natural images. We found that V2 RFs could be broadly classified as V1-like (typical Gabor-shaped subunits), ultralong (subunits with high aspect ratios), or complex-shaped (subunits with multiple oriented components). Furthermore, single-unit recordings from functional domains identified by intrinsic optical imaging showed that neurons with ultralong RFs were primarily localized within pale stripes, whereas neurons with complex-shaped RFs were more concentrated in thin stripes. Thus, by combining single-unit recording with optical imaging and a computational approach, we identified RF subunits underlying spatial feature selectivity of V2 neurons and demonstrated the functional organization of these RF properties. PMID:26839410

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

    Directory of Open Access Journals (Sweden)

    Nabi Shamsaei

    2015-01-01

    Full Text Available Recent evidence has suggested the neuroprotective effects of physical exercise on cerebral ischemic 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 through 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 exercise significantly 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.

  16. 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.

  17. 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-

  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. Dopaminergic modulation of synaptic transmission and neuronal activity patterns in the zebrafish homolog of olfactory cortex

    OpenAIRE

    Schärer, Yan-Ping Zhang; Shum, Jennifer; Moressis, Anastasios; Friedrich, Rainer W.

    2012-01-01

    Dopamine (DA) is an important modulator of synaptic transmission and plasticity that is causally involved in fundamental brain functions and dysfunctions. We examined the dopaminergic modulation of synaptic transmission and sensory responses in telencephalic area Dp of zebrafish, the homolog of olfactory cortex. By combining anatomical tracing and immunohistochemistry, we detected no DA neurons in Dp itself but long-range dopaminergic input from multiple other brain areas. Whole-cell recordin...

  20. Dopaminergic modulation of synaptic transmission and neuronal activity patterns in the zebrafish homolog of olfactory cortex

    OpenAIRE

    Friedrich, Rainer W.

    2012-01-01

    Dopamine (DA) is an important modulator of synaptic transmission and plasticity that is causally involved in fundamental brain functions and dysfunctions. We examined the dopaminergic modulation of synaptic transmission and sensory responses in telencephalic area Dp of zebrafish, the homologue of olfactory cortex. By combining anatomical tracing and immunohistochemistry, we detected no DA neurons in Dp itself but long-range dopaminergic input from multiple other brain areas. Whole-cell record...

  1. Role of orbitofrontal cortex neuronal ensembles in the expression of incubation of heroin craving

    OpenAIRE

    Fanous, Sanya; Goldart, Evan M; Theberge, Florence R.M.; Bossert, Jennifer M.; Shaham, Yavin; Hope, Bruce T

    2012-01-01

    In humans, exposure to cues previously associated with heroin use often provokes relapse after prolonged withdrawal periods. In rats, cue-induced heroin-seeking progressively increases after withdrawal (incubation of heroin craving). Here, we examined the role of orbitofrontal cortex (OFC) neuronal ensembles in the enhanced response to heroin cues after prolonged withdrawal or the expression of incubation of heroin craving. We trained rats to self-administer heroin (6-h/d for 10 d) and assess...

  2. 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...

  3. Acute administration of methylphenidate alters the prefrontal cortex neuronal activity in a dose–response characteristic

    OpenAIRE

    Claussen CM; Dafny N

    2014-01-01

    Catherine M Claussen, Nachum Dafny Department of Neurobiology and Anatomy, University of Texas Health Science Center Medical School at Houston, Houston, TX, USA Abstract: The prefrontal cortex (PFC) is part of the collective structures known as the motive circuit. The PFC acts to enhance higher cognitive functions as well as mediate the effects of psychostimulants. Previous literature shows the importance of PFC neuronal adaptation in response to acute and chronic psychostimulant exposure. T...

  4. Chemogenetic Inactivation of Dorsal Anterior Cingulate Cortex Neurons Disrupts Attentional Behavior in Mouse.

    Science.gov (United States)

    Koike, Hiroyuki; Demars, Michael P; Short, Jennifer A; Nabel, Elisa M; Akbarian, Schahram; Baxter, Mark G; Morishita, Hirofumi

    2016-03-01

    Attention is disrupted commonly in psychiatric disorders, yet mechanistic insight remains limited. Deficits in this function are associated with dorsal anterior cingulate cortex (dACC) excitotoxic lesions and pharmacological disinhibition; however, a causal relationship has not been established at the cellular level. Moreover, this association has not yet been examined in a genetically tractable species such as mice. Here, we reveal that dACC neurons causally contribute to attention processing by combining a chemogenetic approach that reversibly suppresses neural activity with a translational, touchscreen-based attention task in mice. We virally expressed inhibitory hM4Di DREADD (designer receptor exclusively activated by a designer drug) in dACC neurons, and examined the effects of this inhibitory action with the attention-based five-choice serial reaction time task. DREADD inactivation of the dACC neurons during the task significantly increased omission and correct response latencies, indicating that the neuronal activities of dACC contribute to attention and processing speed. Selective inactivation of excitatory neurons in the dACC not only increased omission, but also decreased accuracy. The effect of inactivating dACC neurons was selective to attention as response control, motivation, and locomotion remain normal. This finding suggests that dACC excitatory neurons play a principal role in modulating attention to task-relevant stimuli. This study establishes a foundation to chemogenetically dissect specific cell-type and circuit mechanisms underlying attentional behaviors in a genetically tractable species. PMID:26224620

  5. 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...

  6. Circadian rhythm in adenosine A1 receptor of mouse cerebral cortex

    International Nuclear Information System (INIS)

    In order to investigate diurnal variation in adenosine A1 receptors binding parameters, Bmax and Kd values of specifically bound N6-cyclohexyl-[3H]adenosine were determined in the cerebral cortex of mice that had been housed under controlled light-dark cycles for 4 weeks. Significant differences were found for Bmax values measured at 3-hr intervals across a 24-h period, with low Bmax values during the light period and high Bmax values during the dark period. The amplitude between 03.00 and 18.00 hr was 33%. No substantial rhythm was found in the Kd values. It is suggested that the changes in the density of A1 receptors could reflect a physiologically-relevant mechanism by which adenosine exerts its modulatory role in the central nervous system

  7. 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.

  8. 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.)

  9. Action of aspartate on the /sup 32/Pi incorporation into phospholipids of cerebral cortex

    Energy Technology Data Exchange (ETDEWEB)

    de Scarnati, O.C.; Sato, M.; De Robertis, E.

    1982-02-01

    The effect of L-aspartate on the /sup 32/Pi incorporation of phospholipids, was studied on slices of rat cerebral cortex. This amino acid produced an inhibitory effect in concentrations 0.01-10 mM, which was more evident at 120 min. This effect was not stereospecific and did not imply a change in Pi uptake and in nucleotides approximating P precursors. The inhibition was present in PS, PC, PE and to a lesser extent in Pi. On liver slices 1 mM L-aspartate had the opposite effect, stimulating the incorporation of /sup 32/Pi into total phospholipids. Our results suggest that the effect of L-aspartate is by a non-specific mechanism, probably not mediated by a receptor.

  10. Action of aspartate on the 32Pi incorporation into phospholipids of cerebral cortex

    International Nuclear Information System (INIS)

    The effect of L-aspartate on the 32Pi incorporation of phospholipids, was studied on slices of rat cerebral cortex. This amino acid produced an inhibitory effect in concentrations 0.01-10 mM, which was more evident at 120 min. This effect was not stereospecific and did not imply a change in Pi uptake and in nucleotides approximating P precursors. The inhibition was present in PS, PC, PE and to a lesser extent in Pi. On liver slices 1 mM L-aspartate had the opposite effect, stimulating the incorporation of 32Pi into total phospholipids. Our results suggest that the effect of L-aspartate is by a non-specific mechanism, probably not mediated by a receptor

  11. 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...

  12. Cortical chemoarchitecture shapes macroscale effective functional connectivity patterns in macaque cerebral cortex.

    Science.gov (United States)

    Turk, Elise; Scholtens, Lianne H; van den Heuvel, Martijn P

    2016-05-01

    The mammalian cortex is a complex system of-at the microscale level-interconnected neurons and-at the macroscale level-interconnected areas, forming the infrastructure for local and global neural processing and information integration. While the effects of regional chemoarchitecture on local cortical activity are well known, the effect of local neurotransmitter receptor organization on the emergence of large scale region-to-region functional interactions remains poorly understood. Here, we examined reports of effective functional connectivity-as measured by the action of strychnine administration acting on the chemical balance of cortical areas-in relation to underlying regional variation in microscale neurotransmitter receptor density levels in the macaque cortex. Linking cortical variation in microscale receptor density levels to collated information on macroscale functional connectivity of the macaque cortex, we show macroscale patterns of effective corticocortical functional interactions-and in particular, the strength of connectivity of efferent macroscale pathways-to be related to the ratio of excitatory and inhibitory neurotransmitter receptor densities of cortical areas. Our findings provide evidence for the microscale chemoarchitecture of cortical areas to have a direct stimulating influence on the emergence of macroscale functional connectivity patterns in the mammalian brain. Hum Brain Mapp 37:1856-1865, 2016. © 2016 Wiley Periodicals, Inc. PMID:26970255

  13. 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.

  14. Consciousness without a cerebral cortex: a challenge for neuroscience and medicine.

    Science.gov (United States)

    Merker, Bjorn

    2007-02-01

    A broad range of evidence regarding the functional organization of the vertebrate brain - spanning from comparative neurology to experimental psychology and neurophysiology to clinical data - is reviewed for its bearing on conceptions of the neural organization of consciousness. A novel principle relating target selection, action selection, and motivation to one another, as a means to optimize integration for action in real time, is introduced. With its help, the principal macrosystems of the vertebrate brain can be seen to form a centralized functional design in which an upper brain stem system organized for conscious function performs a penultimate step in action control. This upper brain stem system retained a key role throughout the evolutionary process by which an expanding forebrain - culminating in the cerebral cortex of mammals - came to serve as a medium for the elaboration of conscious contents. This highly conserved upper brainstem system, which extends from the roof of the midbrain to the basal diencephalon, integrates the massively parallel and distributed information capacity of the cerebral hemispheres into the limited-capacity, sequential mode of operation required for coherent behavior. It maintains special connective relations with cortical territories implicated in attentional and conscious functions, but is not rendered nonfunctional in the absence of cortical input. This helps explain the purposive, goal-directed behavior exhibited by mammals after experimental decortication, as well as the evidence that children born without a cortex are conscious. Taken together these circumstances suggest that brainstem mechanisms are integral to the constitution of the conscious state, and that an adequate account of neural mechanisms of conscious function cannot be confined to the thalamocortical complex alone. PMID:17475053

  15. 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

  16. 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...

  17. Low intensity areas observed T2-weighted magnetic resonance imaging of the cerebral cortex in various neurological diseases

    International Nuclear Information System (INIS)

    We retrospectively studied magnetic resonance images of the brain in 158 patients (8 cases of amyotrophic lateral sclerosis, 16 cases of Alzheimer's disease, 8 cases of Parkinson's disease, 53 cases of multiple cerebral infarct, 20 cases of other central nervous system (CNS) diseases, and 53 cases without any CNS disease) to examine the appearance of T2-weighted low signal intensity areas (LIA) in the cerebral cortex. The age of subjects ranged from 36 to 85 years with the mean 65.0 and SD 9.9 years. LIA in the motor and sensory cortices, and brain atrophy were evaluated visually on axial images of the spin-echo sequence obtained with a 1.5 tesla system. The incidence of LIA in the motor cortex was significantly higher in all CNS diseases than in cases without any CNS disease, but not significantly different among CNS diseases. LIA in the motor cortex showed a correlation with age, temporal and parietal atrophy. The appearance of LIA in the sensory cortex correlated with that of LIA in the motor cortex, and parietal atrophy. These results suggest that LIA may appear according to age and be associated with the accumulation of nonheme iron in the cortex, especially in patients with CNS diseases. (author)

  18. Atypically diffuse functional connectivity between caudate nuclei and cerebral cortex in autism

    Directory of Open Access Journals (Sweden)

    Turner Katherine C

    2006-10-01

    Full Text Available Abstract Background Autism is a neurodevelopmental disorder affecting sociocommunicative behavior, but also sensorimotor skill learning, oculomotor control, and executive functioning. Some of these impairments may be related to abnormalities of the caudate nuclei, which have been reported for autism. Methods Our sample was comprised of 8 high-functioning males with autism and 8 handedness, sex, and age-matched controls. Subjects underwent functional MRI scanning during performance on simple visuomotor coordination tasks. Functional connectivity MRI (fcMRI effects were identified as interregional blood oxygenation level dependent (BOLD signal cross-correlation, using the caudate nuclei as seed volumes. Results In the control group, fcMRI effects were found in circuits with known participation of the caudate nuclei (associative, orbitofrontal, oculomotor, motor circuits. Although in the autism group fcMRI effects within these circuits were less pronounced or absent, autistic subjects showed diffusely increased connectivity mostly in pericentral regions, but also in brain areas outside expected anatomical circuits (such as visual cortex. Conclusion These atypical connectivity patterns may be linked to developmental brain growth disturbances recently reported in autism and suggest inefficiently organized functional connectivity between caudate nuclei and cerebral cortex, potentially accounting for stereotypic behaviors and executive impairments.

  19. 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

  20. Influence of the language dominant hemisphere on the activation region of the cerebral cortex during mastication

    International Nuclear Information System (INIS)

    We used functional magnetic resonance imaging (fMRI) to examine the relationship of the activation region of the cerebral cortex during mastication with the language dominant hemisphere. Twelve healthy subjects were asked to chew a special gum 50 times on each side of the mouth, the gum changed color, becoming a deeper red, as it was chewed. The depth of red of the chewed gum was used to ascertain the habitual masticatory side. Measurements were also performed on a conventional whole body 1.5 T clinical scanner using a single shot, multislice echo-planar imaging sequence. The subjects were asked to masticate first on the right side, and then on the left side. As well, they were instructed to do a shiritori test, which is a word game. Computer analysis of the fMRI was done using statistical parametric mapping (SPM) 99 software (p<0.001, paired t-test). We found that the sensorimotor cortex activated by masticatory movements always contains language dominant hemisphere. (author)

  1. 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

  2. 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

  3. 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

  4. 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 ...

  5. Functional MR imaging of cerebral auditory cortex with linguistic and non-linguistic stimulation: preliminary study

    International Nuclear Information System (INIS)

    To obtain preliminary data for understanding the central auditory neural pathway by means of functional MR imaging (fMRI) of the cerebral auditory cortex during linguistic and non-linguistic auditory stimulation. In three right-handed volunteers we conducted fMRI of auditory cortex stimulation at 1.5 T using a conventional gradient-echo technique (TR/TE/flip angle: 80/60/40 deg). Using a pulsed tone of 1000 Hz and speech as non-linguistic and linguistic auditory stimuli, respectively, images-including those of the superior temporal gyrus of both hemispheres-were obtained in sagittal plases. Both stimuli were separately delivered binaurally or monoaurally through a plastic earphone. Images were activated by processing with homemade software. In order to analyze patterns of auditory cortex activation according to type of stimulus and which side of the ear was stimulated, the number and extent of activated pixels were compared between both temporal lobes. Biaural stimulation led to bilateral activation of the superior temporal gyrus, while monoaural stimulation led to more activation in the contralateral temporal lobe than in the ipsilateral. A trend toward slight activation of the left (dominant) temporal lobe in ipsilateral stimulation, particularly with a linguistic stimulus, was observed. During both biaural and monoaural stimulation, a linguistic stimulus produced more widespread activation than did a non-linguistic one. The superior temporal gyri of both temporal lobes are associated with acoustic-phonetic analysis, and the left (dominant) superior temporal gyrus is likely to play a dominant role in this processing. For better understanding of physiological and pathological central auditory pathways, further investigation is needed

  6. Primary motor cortex of the parkinsonian monkey: Altered neuronal responses to muscle stretch

    Directory of Open Access Journals (Sweden)

    Benjamin Pasquereau

    2013-11-01

    Full Text Available Exaggeration of the long-latency stretch reflex (LLSR is a characteristic neurophysiologic feature of Parkinson’s disease (PD that contributes to parkinsonian rigidity. To explore one frequently-hypothesized mechanism, we studied the effects of fast muscle stretches on neuronal activity in the macaque primary motor cortex (M1 before and after the induction of parkinsonism by unilateral administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP. We compared results from the general population of M1 neurons and two antidromically-identified subpopulations: distant-projecting pyramidal-tract type neurons (PTNs and intra-telecenphalic-type corticostriatal neurons (CSNs. Rapid rotations of elbow or wrist joints evoked short-latency responses in 62% of arm-related M1 neurons. As in PD, the late electromyographic responses that constitute the LLSR were enhanced following MPTP. This was accompanied by a shortening of M1 neuronal response latencies and a degradation of directional selectivity, but surprisingly, no increase in single unit response magnitudes. The results suggest that parkinsonism alters the timing and specificity of M1 responses to muscle stretch. Observation of an exaggerated LLSR with no change in the magnitude of proprioceptive responses in M1 is consistent with the idea that the increase in LLSR gain that contributes to parkinsonian rigidity is localized to the spinal cord.

  7. Amyloid-β alters ongoing neuronal activity and excitability in the frontal cortex.

    Science.gov (United States)

    Kellner, Vered; Menkes-Caspi, Noa; Beker, Shlomit; Stern, Edward A

    2014-09-01

    The effects of amyloid-β on the activity and excitability of individual neurons in the early and advanced stages of the pathological progression of Alzheimer's disease remain unknown. We used in vivo intracellular recordings to measure the ongoing and evoked activity of pyramidal neurons in the frontal cortex of APPswe/PS1dE9 transgenic mice and age-matched nontransgenic littermate controls. Evoked excitability was altered in both transgenic groups: neurons in young transgenic mice displayed hypoexcitability, whereas those in older transgenic mice displayed hyperexcitability, suggesting changes in intrinsic electrical properties of the neurons. However, the ongoing activity of neurons in both young and old transgenic groups showed signs of hyperexcitability in the depolarized state of the membrane potential. The membrane potential of neurons in old transgenic mice had an increased tendency to fail to transition to the depolarized state, and the depolarized states had shorter durations on average than did controls. This suggests a combination of both intrinsic electrical and synaptic dysfunctions as mechanisms for activity changes at later stages of the neuropathological progression. PMID:24792906

  8. 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

  9. 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

  10. 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

  11. Glutamatergic system controls synchronization of spontaneous neuronal activity in the murine neonatal entorhinal cortex.

    Science.gov (United States)

    Unichenko, Petr; Yang, Jeng-Wei; Luhmann, Heiko J; Kirischuk, Sergei

    2015-07-01

    Synchronized spontaneous neuronal activity is a characteristic feature of the developing brain. Rhythmic network discharges in the neonatal medial entorhinal cortex (mEC) in vitro depend on activation of ionotropic glutamate receptors, but spontaneously active neurons are required for their initiation. Field potential recordings revealed synchronized neuronal activity in the mEC in vivo developmentally earlier than in vitro. We suggested that not only ionotropic receptors, but also other components of the glutamatergic system modulate neuronal activity in the mEC. Ca(2+) imaging was used to record neuronal activity in neonatal murine brain slices. Two types of spontaneous events were distinguished: global synchronous discharges (synchronous activity) and asynchronously (not synchronized with global discharges) active cells (asynchronous activity). AMPA receptor blockade strongly reduced the frequency of synchronous discharges, while NMDA receptor inhibition was less effective. AMPA and NMDA receptor blockade or activation of group 2/3 metabotropic glutamate receptors (mGluR2/3) completely suppressed synchronous discharges and increased the number of active cells. Blockade of glutamate transporters with DL-TBOA led to NMDA receptor-mediated hyper-synchronization of neuronal activity. Inhibition of NMDA receptors in the presence of DL-TBOA failed to restore synchronous discharges. The latter were partially reestablished only after blockade of mGluR2/3. We conclude that the glutamatergic system can influence neuronal activity via different receptors/mechanisms. As both NMDA and mGluR2/3 receptors have a high affinity for glutamate, changes in extracellular glutamate levels resulting for instance from glutamate transporter malfunction can balance neuronal activity in the mEC, affecting in turn synapse and network formation. PMID:25163767

  12. The changes of regional cerebral blood flow: successful pain relief of intractable CRPS type II patients by motor cortex stimulation

    International Nuclear Information System (INIS)

    Authors report the effectiveness of MCS in extraordinarily extended pain due to intractable CRPS type II and rCBF study result for mechanism of pain control by MCS. A 43-year-old male presented severe spontaneous burning pain in his left hand and forearm and allodynia over the left arm and left hemibody. Authors planned MCS as a neuromodulation therapy for this intractable peripheral neuropathic pain patient because further neurodestructive procedure did not work anymore and have a potential risk of further aggrevation of neuopathic pain. We performed baseline and stimulation brain perfusion SPECT using 20 mCi of Tc-99m ECD. The baseline CBD studies were done with stimulator 'off' state and stimulation studies were done after stimulator 'on' with satisfactory pain relief. For the stimulation study, the radioisotope was injected immediately after pain-relief and the images were taken about 50 minutes after injection of radioisotope. In resting rCBF in the patient was compared with normal control datas, we found significant increase in rCBF in the bilateral prefrontal cortex, right dorsolateral prefrontal cortex, right superior temporal gyrus, left temporooccipital area. When rCBF datas obtained after alleviation of pain with stimulator 'on' . there were significant increase in rCBF in bilateral prefrontal cortex and left temporoocipital area. After subtraction of ECD SPECT, we found significant increase in rCBF in the right premotor and supplementary motor cortex left sensorimotor cortex, right cingulated cortex, right posterior insular cortex, right anterior limb of internal capsule. left orbitofrontal cortex and right pyramidal tract in cerebral peduncle. Authors report exellent pain control by MCS in a case of severe CRPS type II with hemibody involvement and regional cerebral blood flow changes according to successful pain control

  13. 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.

  14. 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.

  15. Hebbian induction of LTP in visual cortex: perforated patch-clamp study in cultured neurons.

    Science.gov (United States)

    Otsu, Y; Kimura, F; Tsumoto, T

    1995-12-01

    1. To see whether presynaptic activation paired with postsynaptic depolarization is necessary for the induction of long-term potentiation (LTP) in visual cortex or whether an activation of postsynaptic receptors in conjunction with depolarization is sufficient, we carried out perforated patch-clamp recordings with nystatin from cultured cortical neurons of rats. 2. Recorded neurons were monosynaptically activated either by electrical stimulation of an adjacent neuron or by direct activation of glutamate on "hot spots" of dendrites through iontophoresis or pressure ejection. In experiments in which cultured neurons were stained immunocytochemically with antibody against synaptophysin after electrophysiological recordings, hot spots were found to correspond to probable synaptic sites. 3. Excitatory postsynaptic currents (EPSCs) evoked by test stimulation applied to the adjacent neuron at 0.1 Hz were recorded at a holding potential of -60 or -70 mV for 5-10 min after an establishment of the whole cell recording configuration. Then, stimulation was paired with postsynaptic depolarization (0 mV for 200 ms) at 1 Hz for 30 or 60 s. LTP of EPSCs was induced in 7 of the 15 cells from which stable recordings were obtained for 18-30 min after pairing. 4. When postsynaptic depolarization was paired with direct glutamate application in the absence of presynaptic stimulation in 12 cells, only 1 showed LTP. Postsynaptic depolarization alone did not induce LTP in any of the six cells tested. Also, presynaptic stimulation alone did not induce LTP in any of the five cells tested. 5. These results suggest that the concurrent activation of presynaptic elements with postsynaptic depolarization is necessary for the induction of LTP in visual cortex. PMID:8747204

  16. Distribution and morphology of nitridergic neurons across functional domains of the rat primary somatosensory cortex

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    Anaelli A Nogueira-Campos

    2012-11-01

    Full Text Available The rat primary somatosensory cortex (S1 is remarkable for its conspicuous vertical compartmentalization in barrels and septal columns, which are additionally stratified in horizontal layers. Whereas excitatory neurons from each of these compartments perform different types of processing, the role of interneurons is much less clear. Among the numerous types of GABAergic interneurons, those producing nitric oxide (NO are especially puzzling, since this gaseous messenger can modulate neural activity, synaptic plasticity and neurovascular coupling. We used a quantitative morphological approach to investigate whether nitrergic interneurons, which might therefore be considered both as NO volume diffusers and as elements of local circuitry, display features that could relate to barrel cortex architecture. In fixed brain sections, nitrergic interneurons can be revealed by histochemical processing for NADPH-diaphorase (NADPHd. Here, the dendritic arbors of nitrergic neurons from different compartments of area S1 were 3D reconstructed from serial 200-μm thick sections, using 100x objective and the Neurolucida system. Standard morphological parameters were extracted for all individual arbors and compared across columns and layers. Wedge analysis was used to compute dendritic orientation indices. Supragranular layers displayed the highest density of nitrergic neurons, whereas layer IV contained nitrergic neurons with largest soma area. The highest nitrergic neuronal density was found in septa, where dendrites were previously characterized as more extense and ramified than in barrels. Dendritic arbors were not confined to the boundaries of the column nor layer of their respective soma, being mostly double-tufted and vertically oriented, except in supragranular layers. These data strongly suggest that nitrergic interneurons adapt their morphology to the dynamics of processing performed by cortical compartments.

  17. 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.

  18. Conantokin probes of NMDA receptors in normal and Alzheimer disease human cerebral cortex

    International Nuclear Information System (INIS)

    Full text: The pharmacology of the N-methyl-D-aspartate (NMDA) receptor site was examined in pathologically affected and relatively spared regions of cerebral cortex tissue obtained at autopsy from Alzheimer disease cases and matched controls. The affinity and density of the [3H]MK-801 binding site were delineated along with the enhancement of [3H]MK-801 binding by glutamate and spermine. Sites with distinct pharmacologies were distributed regionally through the cortex. The differences could not be explained by variations in the parameters of [3H]MK-801 binding; rather, the data suggest that the subunit composition of NMDA receptors may be locally variable. Selective differences were also found between controls and Alzheimer disease cases in certain brain regions. The interactions of human NMDA sites with the Ala(7) and Lys(7) derivatives of conantokin-G (Con-G) were also characterized. Ala(7)-con-G showed the higher affinity of the two peptides, and also defined two distinct binding sites in controls. In distinction to the Ala(7) peptide, Lys(7)- con-G showed preferential binding to receptor sites in Alzheimer disease cf. control brain. Modified conantokins are useful for identifying differences in subunit composition of the NMDA receptors between brain areas. They may also have potential as protective agents against over-excitation mediated by specific NMDA receptors, which might contribute to localized brain damage in Alzheimer disease. For further characterization of the pharmacology of different NMDA receptor subunits, a mammalian expression system has been developed for the analysis of their responses to selected ligands, including conantokins. Copyright (2002) Australian Neuroscience Society

  19. 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.

  20. Higher density of serotonin-1A receptors in the hippocampus and cerebral cortex of alcohol-preferring P rats

    International Nuclear Information System (INIS)

    Saturable [3H]-80HDPAT binding to 5HT-1A receptors in membranes prepared from hippocampus and frontal cerebral cortex of alcohol-preferring (P) rats and of alcohol-nonpreferring (NP) rats has been compared. The Bmax values or densities of recognition sites for 5HT-1A receptors in both brain areas of the P rats are 38 and 44 percent lower in the P rats than in the NP rats. The corresponding KD values are 38 and 44 percent lower in the P rats than in the NP rats, indicating higher affinities of the recognition sites for the 5HT-1A receptors in hippocampus and cerebral cortex of the P rats. These findings indicate either an enrichment of 5HT-1A receptor density during selective breeding for alcohol preference or an upregulation of 5HT-1A receptors of 5HT found in these brain areas of P rats as compared with the NP rats

  1. 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

    microscopy, and transmission electron microscopy techniques, we analyze the proliferation behavior of microglial cells and astrocytes. We also investigate possible motor neuron death in the mouse motor cortex at different stages of the wobbler disease, which so far has not received much attention. Results An...... area show caspase 3 activation indicating neurodegenerative processes, which may cause progressive paralysis of the WR mice. It could also cause cell degeneration, such as vacuolization, dilation of the ER, and swollen mitochondria at the same time, and support the assumption that inflammation might be...... the immune response is primary or secondary and how harmful or beneficial it is in the WR motor neuron disease, anti-inflammatory treatment might be considered....

  2. The Ascending Reticular Activating System in a Patient With Severe Injury of the Cerebral Cortex: A Case Report.

    Science.gov (United States)

    Jang, Sung Ho; Lee, Han Do

    2015-10-01

    We reported on the ascending reticular activating system (ARAS) finding of a patient in whom severe injury of the cerebral cortex was detected following a hypoxic-ischemic brain injury (HIBI).A 67-year-old female patient who suffered from HIBI induced by cardiac arrest after surgery for lumbar disc herniation underwent cardiopulmonary resuscitation approximately 20 to 30 minutes after cardiac arrest. The patient exhibited impaired alertness, with a Glasgow Coma Scale (GCS) score of 4 (eye opening: 2, best verbal response: 1, and best motor response: 1). Approximately 3 years after onset, she began to whimper sometimes and showed improved consciousness, with a GCS score of 10 (eye opening: 4, best verbal response: 2, and best motor response: 4) and Coma Recovery Scale-Revised score of 9 (auditory function: 1, visual function: 1, motor function: 2, verbal function: 2, communication: 1, and arousal: 2).Results of diffusion tensor tractography for the upper connectivity of the ARAS showed decreased neural connectivity to each cerebral cortex in both hemispheres. The right lower ARAS between the pontine reticular formation and the thalamic intralaminar nuclei (ILN) was thinner compared with the left side.Severe injury of the upper portion of the ARAS between the thalamic ILN and cerebral cortex was demonstrated in a patient with some level of consciousness. PMID:26496328

  3. 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.

  4. Experience-dependent plasticity of dendritic spines of layer 2/3 pyramidal neurons in the mouse cortex.

    Science.gov (United States)

    Ma, Lei; Qiao, Qian; Tsai, Jin-Wu; Yang, Guang; Li, Wei; Gan, Wen-Biao

    2016-03-01

    Previous studies have shown that sensory and motor experiences play an important role in the remodeling of dendritic spines of layer 5 (L5) pyramidal neurons in the cortex. In this study, we examined the effects of sensory deprivation and motor learning on dendritic spine remodeling of layer 2/3 (L2/3) pyramidal neurons in the barrel and motor cortices. Similar to L5 pyramidal neurons, spines on apical dendrites of L2/3 pyramidal neurons are plastic during development and largely stable in adulthood. Sensory deprivation via whisker trimming reduces the elimination rate of existing spines without significant effect on the rate of spine formation in the developing barrel cortex. Furthermore, we show that motor training increases the formation and elimination of dendritic spines in the primary motor cortex. Unlike L5 pyramidal neurons, however, there is no significant difference in the rate of spine formation between sibling dendritic branches of L2/3 pyramidal neurons. Our studies indicate that sensory and motor learning experiences have important impact on dendritic spine remodeling in L2/3 pyramidal neurons. They also suggest that the rules governing experience-dependent spine remodeling are largely similar, but not identical, between L2/3 and L5 pyramidal neurons. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 76: 277-286, 2016. PMID:26033635

  5. Dopaminergic modulation of synaptic transmission and neuronal activity patterns in the zebrafish homolog of olfactory cortex

    Directory of Open Access Journals (Sweden)

    Rainer W. Friedrich

    2012-10-01

    Full Text Available Dopamine (DA is an important modulator of synaptic transmission and plasticity that is causally involved in fundamental brain functions and dysfunctions. We examined the dopaminergic modulation of synaptic transmission and sensory responses in telencephalic area Dp of zebrafish, the homologue of olfactory cortex. By combining anatomical tracing and immunohistochemistry, we detected no DA neurons in Dp itself but long-range dopaminergic input from multiple other brain areas. Whole-cell recordings revealed no obvious effects of DA on membrane potential or input resistance in the majority of Dp neurons. Electrical stimulation of the olfactory tracts produced a complex sequence of synaptic currents in Dp neurons. DA selectively decreased inhibitory currents with little or no effect on excitatory components. Multiphoton calcium imaging showed that population responses of Dp neurons to olfactory tract stimulation or odor application were enhanced by DA, consistent with its effect on inhibitory synaptic transmission. These effects of DA were blocked by an antagonist of D2-like receptors. DA therefore disinhibits and reorganizes sensory responses in Dp. This modulation may affect sensory perception and could be involved in the experience-dependent modification of odor representations.

  6. A Golgi deimpregnation study of neurons in the rhesus monkey visual cortex (areas 17 and 18).

    Science.gov (United States)

    Werner, L; Winkelmann, E; Koglin, A; Neser, J; Rodewohl, H

    1989-01-01

    The morphological features of 298 neurons impregnated according to Golgi-Kopsch in areas 17 and 18 of Macaca mulatta were analyzed, and the same neurons were deimpregnated to visualize structural details of the somata in different types of neurons. The following cell types were investigated: Pyramidal and pyramid-like cells, spiny stellate cells, double bouquet cells, bipolar cells, chandelier cells, neurogliaform cells, basket and related cells. This procedure allows the evaluation of the nuclear-cytoplasmic proportion and the position of the nucleus besides shape and size of the cell body. Pyramidal and pyramid-like cells (N = 43), spiny stellate cells (N = 26), basket and related cells (N = 126) are variable in these features. A positive correlation between soma size and width of the cytoplasm is found in pyramidal, pyramid-like cells and spiny stellate cells. With the exception of some large somata in both these types of neurons the nucleus is found in a central position. Double bouquet cells (N = 6), bipolar cells (N = 13) and chandelier cells (N = 11) exhibit small cytoplasmic rims and centrally located nuclei. The small somata of neurogliaform cells (N = 37), however, and the small to very large somata of basket and related cells show broad cytoplasmic portions surrounding the eccentrically located nuclei. These findings allow the identification of different neuronal types in Nissl-stained sections on the basis of these soma features. This is a prerequisite for further detailed quantitative studies on the laminar distribution of different neuronal types in the visual cortex of the monkey. PMID:2610391

  7. 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

  8. 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

  9. The fuzzy brain. Vagueness and mapping connectivity of the human cerebral cortex

    Science.gov (United States)

    Haueis, Philipp

    2012-01-01

    While the past century of neuroscientific research has brought considerable progress in defining the boundaries of the human cerebral cortex, there are cases in which the demarcation of one area from another remains fuzzy. Despite the existence of clearly demarcated areas, examples of gradual transitions between areas are known since early cytoarchitectonic studies. Since multi-modal anatomical approaches and functional connectivity studies brought renewed attention to the topic, a better understanding of the theoretical and methodological implications of fuzzy boundaries in brain science can be conceptually useful. This article provides a preliminary conceptual framework to understand this problem by applying philosophical theories of vagueness to three levels of neuroanatomical research. For the first two levels (cytoarchitectonics and fMRI studies), vagueness will be distinguished from other forms of uncertainty, such as imprecise measurement or ambiguous causal sources of activation. The article proceeds to discuss the implications of these levels for the anatomical study of connectivity between cortical areas. There, vagueness gets imported into connectivity studies since the network structure is dependent on the parcellation scheme and thresholds have to be used to delineate functional boundaries. Functional connectivity may introduce an additional form of vagueness, as it is an organizational principle of the brain. The article concludes by discussing what steps are appropriate to define areal boundaries more precisely. PMID:22973199

  10. 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. PMID:25092805

  11. 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

  12. 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

  13. 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.

  14. [Types of neurons in the visual cortex of the rat, identified in Nissl- and deimpregnated Golgi preparations].

    Science.gov (United States)

    Werner, L; Hedlich, A; Winkelmann, E

    1985-01-01

    Neuronal types of the rat's visual cortex were identified in Nissl stained and deimpregnated Golgi sections (rapid Golgi method modified by Fairén et al. 1977, Golgi-Bubenaite, Golgi-Kopsch and modified by Braitenberg; deimpregnation after FAIREN et al. 1977 and Braak and Braak 1982, respectively). Cytoplasm and nucleus become visible in deimpregnated neurons and can then be counter-stained with methylene blue or toluidin blue. Somal and nuclear features of Nissl stained and deimpregnated neurons were compared. Provided that these features as well as the specific localization, the relative size and the shape of the soma agree the neurons are identical. We could find that the following neuronal types are identical in Golgi and Nissl stained sections: pyramidal cells of layers II-VI, pyramid-like neurons of layers VI and VII (VIa, b, c) (type C, Werner et al. 1982), multiangular neurons of layer I (type A, Werner et al. 1982), spiny stellate cells of layer IV, sparsely spined neurons with ascending axons (Martinotti cells) (type H, Werner et al. 1982), large and medium-sized spine-free, multipolar neurons (basket cells) (type B, Werner et al. 1982). Bipolar neurons and chandelier cells are identical with neurons poor in cytoplasm (types E, F, G, Werner et al. 1982). Until today two neuronal types could not be identified: type D of L I (Werner et al. 1982) and small, sparsely-spined neurons of layer IV with variable axons (Hedlich and Winkelmann 1982; Hedlich et al. 1984). Characteristics of somata, dendrites and axons of neurons identified in this paper are summarized in table 1. In most cases, these findings confirm earlier suppositions concerning the identity of neuronal types of the rat's visual cortex in Golgi and Nissl stained sections (Werner et al. 1979) and verify the values of their frequency and distribution pattern (Werner et al. 1982). PMID:2410488

  15. 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.)

  16. 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.

  17. The Neuron-Astrocyte-Microglia Triad in a Rat Model of Chronic Cerebral Hypoperfusion: Protective Effect of Dipyridamole

    OpenAIRE

    Daniele Lana; Felicita Pedata; Maria Grazia Giovannini

    2014-01-01

    Chronic cerebral hypoperfusion during aging may cause progressive neurodegeneration as ischemic conditions persist. Proper functioning of the interplay between neurons and glia is fundamental for the functional organization of the brain. The aim of our research was to study the pathophysiological mechanisms, and particularly the derangement of the interplay between neurons and astrocytes-microglia with the formation of “triads,” in a model of chronic cerebral hypoperfusion induced by the two-...

  18. Effect of hyperbaric oxygenation on mitochondrial function of neuronal cells in the cortex of neonatal rats after hypoxic-ischemic brain damage

    Directory of Open Access Journals (Sweden)

    L. Yang

    2016-01-01

    Full Text Available The timing and mechanisms of protection by hyperbaric oxygenation (HBO in hypoxic-ischemic brain damage (HIBD have only been partially elucidated. We monitored the effect of HBO on the mitochondrial function of neuronal cells in the cerebral cortex of neonatal rats after HIBD. Neonatal Sprague-Dawley rats (total of 360 of both genders were randomly divided into normal control, HIBD, and HIBD+HBO groups. The HBO treatment began immediately after hypoxia-ischemia (HI and continued once a day for 7 consecutive days. Animals were euthanized 0, 2, 4, 6, and 12 h post-HI to monitor the changes in mitochondrial membrane potential (ΔΨm occurring soon after a single dose of HBO treatment, as well as 2, 3, 4, 5, 6, and 7 days post-HI to study ΔΨm changes after a series of HBO treatments. Fluctuations in ΔΨm were observed in the ipsilateral cortex in both HIBD and HIBD+HBO groups. Within 2 to 12 h after HI insult, the ΔΨm of the HIBD and HIBD+HBO groups recovered to some extent. A secondary drop in ΔΨm was observed in both groups during the 1-4 days post-HI period, but was more severe in the HIBD+HBO group. There was a secondary recovery of ΔΨm observed in the HIBD+HBO group, but not in the HIBD group, during the 5-7 days period after HI insult. HBO therapy may not lead to improvement of neural cell mitochondrial function in the cerebral cortex in the early stage post-HI, but may improve it in the sub-acute stage post-HI.

  19. Effect of hyperbaric oxygenation on mitochondrial function of neuronal cells in the cortex of neonatal rats after hypoxic-ischemic brain damage.

    Science.gov (United States)

    Yang, L; Hei, M Y; Dai, J J; Hu, N; Xiang, X Y

    2016-01-01

    The timing and mechanisms of protection by hyperbaric oxygenation (HBO) in hypoxic-ischemic brain damage (HIBD) have only been partially elucidated. We monitored the effect of HBO on the mitochondrial function of neuronal cells in the cerebral cortex of neonatal rats after HIBD. Neonatal Sprague-Dawley rats (total of 360 of both genders) were randomly divided into normal control, HIBD, and HIBD+HBO groups. The HBO treatment began immediately after hypoxia-ischemia (HI) and continued once a day for 7 consecutive days. Animals were euthanized 0, 2, 4, 6, and 12 h post-HI to monitor the changes in mitochondrial membrane potential (ΔΨm) occurring soon after a single dose of HBO treatment, as well as 2, 3, 4, 5, 6, and 7 days post-HI to study ΔΨm changes after a series of HBO treatments. Fluctuations in ΔΨm were observed in the ipsilateral cortex in both HIBD and HIBD+HBO groups. Within 2 to 12 h after HI insult, the ΔΨm of the HIBD and HIBD+HBO groups recovered to some extent. A secondary drop in ΔΨm was observed in both groups during the 1-4 days post-HI period, but was more severe in the HIBD+HBO group. There was a secondary recovery of ΔΨm observed in the HIBD+HBO group, but not in the HIBD group, during the 5-7 days period after HI insult. HBO therapy may not lead to improvement of neural cell mitochondrial function in the cerebral cortex in the early stage post-HI, but may improve it in the sub-acute stage post-HI. PMID:27119428

  20. 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...

  1. Early immature neuronal death is partially involved in memory impairment induced by cerebral ischemia.

    Science.gov (United States)

    Yi, Jee Hyun; Cho, So Yeon; Jeon, Se Jin; Jung, Ji Wook; Park, Man Seok; Kim, Dong Hyun; Ryu, Jong Hoon

    2016-07-15

    Memory impairment is a common after an ischemic stroke. While delayed neuronal death in the CA1 region is usually linked to cerebral ischemia-induced memory impairment, the role of early immature neuronal death within the DG region in the memory state of an ischemic stroke model has rarely been studied. Here, we show a partial role of immature neuronal death in memory impairment in a global ischemia model. We found early immature neuronal death, which was determined by DCX and NeuN-double-staining. Injection of z-DEVD-fmk, a caspase-3 inhibitor, into the DG region rescued cells from immature neuronal death in the DG region without affecting delayed neuronal death in the CA1 region of an ischemic brain. Moreover, z-DEVD-fmk treatment partially rescued ischemia-induced spatial memory impairment. We also found that ischemia-induced LTP impairment in the perforant pathway was restored by z-DEVD-fmk treatment. These results suggest that early immature neuronal death is partially involved in ischemia-induced spatial memory impairment. PMID:27085588

  2. Production rates and turnover of triiodothyronine in rat-developing cerebral cortex and cerebellum. Responses to hypothyroidism

    International Nuclear Information System (INIS)

    Local 5'-deiodination of serum thyroxine (T4) is the main source of triiodothyronine (T3) for the brain. Since we noted in previous studies that the cerebral cortex of neonatal rats tolerated marked reductions in serum T4 without biochemical hypothyroidism, we examined the in vivo T4 and T3 metabolism in that tissue and in the cerebellum of euthyroid and hypothyroid 2-wk-old rats. We also assessed the contribution of enhanced tissue T4 to T3 conversion and decreased T3 removal from the tissues to the T3 homeostasis in hypothyroid brain. Congenital and neonatal hypothyroidism was induced by adding methimazole to the drinking water. Serum, cerebral cortex (Cx), cerebellum (Cm), liver (L) and kidney (R) concentrations of 125I-T4, 125I-T3(T4), and 131I-T3 were measured at various times after injecting 125I-T4 and 131I-T3. The rate of T3 removal from the tissues was measured after injecting an excess of anti-T3-antibody to rats previously injected with tracer T3. In hypothyroidism, the fractional removal rates and clearances were reduced in all tissues, in cortex and cerebellum by 70%, and in liver and kidney ranging from 30 to 50%. While greater than 80% of the 125I-T3(T4) in the brain tissues of euthyroid rats was locally produced, in hypothyroid cerebral cortex and cerebellum the integrated concentrations of 125I-T3(T4) were 2.7- and 1.5-fold greater than in euthyroid rats

  3. 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

  4. 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

  5. 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.

  6. 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

  7. Dynamic social adaptation of motion-related neurons in primate parietal cortex.

    Directory of Open Access Journals (Sweden)

    Naotaka Fujii

    Full Text Available Social brain function, which allows us to adapt our behavior to social context, is poorly understood at the single-cell level due largely to technical limitations. But the questions involved are vital: How do neurons recognize and modulate their activity in response to social context? To probe the mechanisms involved, we developed a novel recording technique, called multi-dimensional recording, and applied it simultaneously in the left parietal cortices of two monkeys while they shared a common social space. When the monkeys sat near each other but did not interact, each monkey's parietal activity showed robust response preference to action by his own right arm and almost no response to action by the other's arm. But the preference was broken if social conflict emerged between the monkeys-specifically, if both were able to reach for the same food item placed on the table between them. Under these circumstances, parietal neurons started to show complex combinatorial responses to motion of self and other. Parietal cortex adapted its response properties in the social context by discarding and recruiting different neural populations. Our results suggest that parietal neurons can recognize social events in the environment linked with current social context and form part of a larger social brain network.

  8. Increased 20-HETE synthesis explains reduced cerebral blood flow but not impaired neurovascular coupling after cortical spreading depression in rat cerebral cortex

    DEFF Research Database (Denmark)

    Fordsmann, Jonas Christoffer; ko, Rebecca; Choi, Hyun B;

    2013-01-01

    Cortical spreading depression (CSD) is associated with release of arachidonic acid (AA), impaired neurovascular coupling, and reduced cerebral blood flow (CBF), caused by cortical vasoconstriction. We tested the hypothesis that the released AA is metabolized by the cytochrome P450 enzyme to produce...... the vasoconstrictor 20-hydroxyeicosatetraenoic acid (20-HETE), and that this mechanism explains cortical vasoconstriction and vascular dysfunction after CSD. CSD was induced in the frontal cortex of rats and the cortical electrical activity and local field potentials (LFPs) recorded by glass...

  9. 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

  10. General indices to characterize the electrical response of the cerebral cortex to TMS.

    Science.gov (United States)

    Casali, Adenauer G; Casarotto, Silvia; Rosanova, Mario; Mariotti, Maurizio; Massimini, Marcello

    2010-01-15

    Transcranial magnetic stimulation (TMS) combined with simultaneous high-density electroencephalography (hd-EEG) represents a straightforward way to gauge cortical excitability and connectivity in humans. However, the analysis, classification and interpretation of TMS-evoked potentials are hampered by scarce a priori knowledge about the physiological effect of TMS and by lack of an established data analysis framework. Here, we implemented a standardized, data-driven procedure to characterize the electrical response of the cerebral cortex to TMS by means of three synthetic indices: significant current density (SCD), phase-locking (PL) and significant current scattering (SCS). SCD sums up the amplitude of all significant currents induced by TMS, PL reflects the ability of TMS to reset the phase of ongoing cortical oscillations, while SCS measures the average distance of significantly activated sources from the site of stimulation. These indices are aimed at capturing different aspects of brain responsiveness, ranging from global cortical excitability towards global cortical connectivity. We analyzed the EEG responses to TMS of Brodmann's area 19 at increasing intensities in five healthy subjects. The spatial distribution and time course of SCD, PL and SCS revealed a reproducible profile of excitability and connectivity, characterized by a local activation threshold around a TMS-induced electric field of 50 V/m and by a selective propagation of TMS-evoked activation from occipital to ipsilateral frontal areas that reached a maximum at 70-100 ms. These general indices may be used to characterize the effects of TMS on any cortical area and to quantitatively evaluate cortical excitability and connectivity in physiological and pathological conditions. PMID:19770048

  11. Evidence that two stereochemically different alpha-2 adrenoceptors modulate norepinephrine release in rat cerebral cortex

    International Nuclear Information System (INIS)

    Cerebral cortex slices from the rat were loaded with [3H]norepinephrine ([3H]NE) and superfused in order to measure the release of radioactivity at rest and in response to electrical stimulation. The (-)-isomer and the (+)-isomer of CH-38083 (7,8-(methylenedioxy)-14- alpha-hydroxyalloberbane HCl), a selective alpha-2-adrenoceptor antagonist with an alloberbane skeleton, increased the electrically induced release of [3H]NE in a concentration-dependent manner, and a similar effect was observed with racemic CH-38083 and idazoxan. The stereoisomers of CH-38083 applied in a concentration range of 10(-8) to 10(-6) mol/l were equipotent in facilitating stimulation-evoked [3H]NE release: concentrations needed to enhance tritium outflow by 50% were 1.3 X 10(-7) mol/l for (-)-CH-38083 and 1.4 X 10(-7) mol/l for (+)-CH-38083. Exogenous NE decreased the electrically stimulated release of [3H]NE, and the stereoisomers of CH-38083 antagonized this inhibition with different potencies: the dissociation constant (KB) values for (-)-isomer and for (+)-isomer of CH-38083 were 14.29 and 97.18 nmol/l. These data indicate that presynaptic alpha-2 adrenoceptors that are available for NE released from axon terminals do not show stereospecificity toward enantiomers of CH-38083, whereas those that are occupied by exogenous NE are much more sensitive toward (-)-CH-38083. The alpha-1 adrenoceptor antagonist prazosin also differentiated between the alpha-2 adrenoceptor subtypes: prazosin (10(-6) mol/l) did not alter the increase of electrically induced [3H]NE release evoked by (-)- and (+)-CH-38083; however, in its presence, the stereoisomers of CH-38083 failed to antagonize the inhibitory effect of exogenous NE on its own release

  12. Differential binding of 3H-imipramine and 3H-mianserin in rat cerebral cortex

    International Nuclear Information System (INIS)

    Drug competition profiles, effect of raphe lesion, and sodium dependency of the binding of two antidepressant drugs 3H-imipramine and 3H-mianserin to rat cerebral cortex homogenate were compared to examine whether the drugs bound to a common ''antidepressant receptor.'' Of the neurotransmitters tested, only serotonin displaced binding of both 3H-imipramine and 3H-mianserin. 3H-Mianserin binding was potently displaced by serotonin S2 antagonists and exhibited a profile similar to that of 3H-spiperone binding. In the presence of the serotonin S2 antagonist spiperone, antihistamines (H1) potently displaced 3H-mianserin binding. 3H-Imipramine binding was displaced potently by serotonin uptake inhibitors. The order of potency of serotonergic drugs in displacing 3H-imipramine binding was not similar to their order in displacing 3H-spiperone or -3H-serotonin binding. Prior midbrain raphe lesions greatly decreased the binding of 3H-imipramine but did not alter binding of 3H-mianserin. Binding of 3H-imipramine but not 3H-mianserin was sodium dependent. These results show that 3H-imipramine and 3H-mianserin bind to different receptors. 3H-Imipramine binds to a presynaptic serotonin receptor which is probably related to a serotonin uptake recognition site, the binding of which is sodium dependent. 3H-Mianserin binds to postsynaptic receptors, possibly both serotonin S2 and histamine H1 receptors, the binding of which is sodium independent

  13. Blood flow and oxygenation changes due to low-frequency repetitive transcranial magnetic stimulation of the cerebral cortex

    Science.gov (United States)

    Mesquita, Rickson C.; Faseyitan, Olufunsho K.; Turkeltaub, Peter E.; Buckley, Erin M.; Thomas, Amy; Kim, Meeri N.; Durduran, Turgut; Greenberg, Joel H.; Detre, John A.; Yodh, Arjun G.; Hamilton, Roy H.

    2013-06-01

    Transcranial magnetic stimulation (TMS) modulates processing in the human brain and is therefore of interest as a treatment modality for neurologic conditions. During TMS administration, an electric current passing through a coil on the scalp creates a rapidly varying magnetic field that induces currents in the cerebral cortex. The effects of low-frequency (1 Hz), repetitive TMS (rTMS) on motor cortex cerebral blood flow (CBF) and tissue oxygenation in seven healthy adults, during/after 20 min stimulation, is reported. Noninvasive optical methods are employed: diffuse correlation spectroscopy (DCS) for blood flow and diffuse optical spectroscopy (DOS) for hemoglobin concentrations. A significant increase in median CBF (33%) on the side ipsilateral to stimulation was observed during rTMS and persisted after discontinuation. The measured hemodynamic parameter variations enabled computation of relative changes in cerebral metabolic rate of oxygen consumption during rTMS, which increased significantly (28%) in the stimulated hemisphere. By contrast, hemodynamic changes from baseline were not observed contralateral to rTMS administration (all parameters, p>0.29). In total, these findings provide new information about hemodynamic/metabolic responses to low-frequency rTMS and, importantly, demonstrate the feasibility of DCS/DOS for noninvasive monitoring of TMS-induced physiologic effects.

  14. Multi-Scale Entrainment of Coupled Neuronal Oscillations in Primary Auditory Cortex.

    Science.gov (United States)

    O'Connell, M N; Barczak, A; Ross, D; McGinnis, T; Schroeder, C E; Lakatos, P

    2015-01-01

    Earlier studies demonstrate that when the frequency of rhythmic tone sequences or streams is task relevant, ongoing excitability fluctuations (oscillations) of neuronal ensembles in primary auditory cortex (A1) entrain to stimulation in a frequency dependent way that sharpens frequency tuning. The phase distribution across A1 neuronal ensembles at time points when attended stimuli are predicted to occur reflects the focus of attention along the spectral attribute of auditory stimuli. This study examined how neuronal activity is modulated if only the temporal features of rhythmic stimulus streams are relevant. We presented macaques with auditory clicks arranged in 33 Hz (gamma timescale) quintets, repeated at a 1.6 Hz (delta timescale) rate. Such multi-scale, hierarchically organized temporal structure is characteristic of vocalizations and other natural stimuli. Monkeys were required to detect and respond to deviations in the temporal pattern of gamma quintets. As expected, engagement in the auditory task resulted in the multi-scale entrainment of delta- and gamma-band neuronal oscillations across all of A1. Surprisingly, however, the phase-alignment, and thus, the physiological impact of entrainment differed across the tonotopic map in A1. In the region of 11-16 kHz representation, entrainment most often aligned high excitability oscillatory phases with task-relevant events in the input stream and thus resulted in response enhancement. In the remainder of the A1 sites, entrainment generally resulted in response suppression. Our data indicate that the suppressive effects were due to low excitability phase delta oscillatory entrainment and the phase amplitude coupling of delta and gamma oscillations. Regardless of the phase or frequency, entrainment appeared stronger in left A1, indicative of the hemispheric lateralization of auditory function. PMID:26696866

  15. Multi-scale entrainment of coupled neuronal oscillations in primary auditory cortex.

    Directory of Open Access Journals (Sweden)

    Monica Noelle O'Connell

    2015-12-01

    Full Text Available Earlier studies demonstrate that when the frequency of rhythmic tone sequences or streams is task relevant, ongoing excitability fluctuations (oscillations of neuronal ensembles in primary auditory cortex (A1 entrain to stimulation in a frequency dependent way that sharpens frequency tuning. The phase distribution across A1 neuronal ensembles at time points when attended stimuli are predicted to occur reflects the focus of attention along the spectral attribute of auditory stimuli. This study examined how neuronal activity is modulated if only the temporal features of rhythmic stimulus streams are relevant. We presented macaques with auditory clicks arranged in 33 Hz (gamma timescale quintets, repeated at a 1.6 Hz (delta timescale rate. Such multi-scale, hierarchically organized temporal structure is characteristic of vocalizations and other natural stimuli. Monkeys were required to detect and respond to deviations in the temporal pattern of gamma quintets. As expected, engagement in the auditory task resulted in the multi-scale entrainment of delta- and gamma-band neuronal oscillations across all of A1. Surprisingly, however, the phase-alignment, and thus, the physiological impact of entrainment differed across the tonotopic map in A1. In the region of 11-16 kHz representation, entrainment most often aligned high excitability oscillatory phases with task-relevant events in the input stream and thus resulted in response enhancement. In the remainder of the A1 sites, entrainment generally resulted in response suppression. Our data indicate that the suppressive effects were due to low excitability phase delta oscillatory entrainment and the phase amplitude coupling of delta and gamma oscillations. Regardless of the phase or frequency, entrainment appeared stronger in left A1, indicative of the hemispheric lateralization of auditory function.

  16. 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.

  17. Neuronal codes for the inhibitory control of impulsive actions in the rat infralimbic cortex.

    Science.gov (United States)

    Tsutsui-Kimura, Iku; Ohmura, Yu; Izumi, Takeshi; Matsushima, Toshiya; Amita, Hidetoshi; Yamaguchi, Taku; Yoshida, Takayuki; Yoshioka, Mitsuhiro

    2016-01-01

    Poor impulse control is a debilitating condition observed in various psychiatric disorders and could be a risk factor for drug addiction, criminal involvement, and suicide. The rat infralimbic cortex (IL), located in the ventral portion of the medial prefrontal cortex, has been implicated in impulse control. To elucidate the neurophysiological basis of impulse control, we recorded single unit activity in the IL of a rat performing a 3-choiceserial reaction time task (3-CSRTT) and 2-choice task (2-CT), which are animal models for impulsivity. The inactivation of IL neuronal activity with an injection of muscimol (0.1 μg /side) disrupted impulse control in the 3-CSRTT. More than 60% (38/56) of isolated IL units were linked to impulse control, while approximately 30% of all units were linked to attentional function in the 3-CSRTT. To avoid confounding motor-related units with the impulse control-related units, we further conducted the 2-CT in which the animals' motor activities were restricted during recording window. More than 30% (14/44) of recorded IL units were linked to impulse control in the 2-CT. Several types of impulse control-related units were identified. Only 16% of all units were compatible with the results of the muscimol experiment, which showed a transient decline in the firing rate immediately before the release of behavioral inhibition. This is the first study to elucidate the neurophysiological basis of impulse control in the IL and to propose that IL neurons control impulsive actions in a more complex manner than previously considered. PMID:26341319

  18. 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.

  19. Neuronal activity in primate auditory cortex during the performance of audiovisual tasks.

    Science.gov (United States)

    Brosch, Michael; Selezneva, Elena; Scheich, Henning

    2015-03-01

    This study aimed at a deeper understanding of which cognitive and motivational aspects of tasks affect auditory cortical activity. To this end we trained two macaque monkeys to perform two different tasks on the same audiovisual stimulus and to do this with two different sizes of water rewards. The monkeys had to touch a bar after a tone had been turned on together with an LED, and to hold the bar until either the tone (auditory task) or the LED (visual task) was turned off. In 399 multiunits recorded from core fields of auditory cortex we confirmed that during task engagement neurons responded to auditory and non-auditory stimuli that were task-relevant, such as light and water. We also confirmed that firing rates slowly increased or decreased for several seconds during various phases of the tasks. Responses to non-auditory stimuli and slow firing changes were observed during both the auditory and the visual task, with some differences between them. There was also a weak task-dependent modulation of the responses to auditory stimuli. In contrast to these cognitive aspects, motivational aspects of the tasks were not reflected in the firing, except during delivery of the water reward. In conclusion, the present study supports our previous proposal that there are two response types in the auditory cortex that represent the timing and the type of auditory and non-auditory elements of a auditory tasks as well the association between elements. PMID:25728179

  20. 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.

  1. Production rates and turnover of triiodothyronine in rat-developing cerebral cortex and cerebellum. Responses to hypothyroidism.

    OpenAIRE

    J.E. Silva; Matthews, P S

    1984-01-01

    Local 5'-deiodination of serum thyroxine (T4) is the main source of triiodothyronine (T3) for the brain. Since we noted in previous studies that the cerebral cortex of neonatal rats tolerated marked reductions in serum T4 without biochemical hypothyroidism, we examined the in vivo T4 and T3 metabolism in that tissue and in the cerebellum of euthyroid and hypothyroid 2-wk-old rats. We also assessed the contribution of enhanced tissue T4 to T3 conversion and decreased T3 removal from the tissue...

  2. 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...

  3. 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...

  4. Sizes and distributions of intrinsic neurons incorporating tritiated GABA in monkey sensory-motor cortex

    International Nuclear Information System (INIS)

    Neurons accumulating [3H]gamma-aminobutyric acid (GABA) were identified autoradiographically in frozen and plastic sections after injection of the material in the monkey somatic sensory (areas 3, 1, and 2), motor (area 4), and parietal (area 5) cortex following intravenous administration of a GABA transaminase inhibitor, amino-oxyacetic acid. Two general forms of labeled cells are recognized: those with large diameter (15- to 20-micrometer) somata, probably corresponding to the basket cells of Golgi studies, and those with small diameter (6- to 12-micrometer) somata, probably corresponding to several other types. The sizes and laminar distributions of labeled cells in the cytoarchitectonic fields of the first somatic sensory are (SI) are similar. In these areas, the greatest concentrations of labeled cells are in layer II, in layer IV, and in the superficial stratum of layer IV. In area 5, there are many fewer labeled cells in layer IV. In area 4, the labeled cells are larger and distributed more homogeneously, though there are fewer in layer VI. The large labeled cell type is concentrated in layers III and V of all areas. The smaller labeled types are found in all other layers, including layer I. In layer IV, they form approximately 40% of the total small-celled neuronal population

  5. 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 ...

  6. Physiological activation of the human cerebral cortex during auditory perception and speech revealed by regional increases in cerebral blood flow

    DEFF Research Database (Denmark)

    Lassen, N A; Friberg, L

    1988-01-01

    methods, that are based of the use of radioactive tracers, can be applied in the same manner for mapping cortex activity. In particular single photon tomography SPECT is readily applicable to clinical audiology, so that the cortical components of the auditory processing can be more closely investigated....

  7. 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...

  8. 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.

  9. EAAC1 Gene Deletion Increases Neuronal Death and Blood Brain Barrier Disruption after Transient Cerebral Ischemia in Female Mice

    Directory of Open Access Journals (Sweden)

    Bo Young Choi

    2014-10-01

    Full Text Available EAAC1 is important in modulating brain ischemic tolerance. Mice lacking EAAC1 exhibit increased susceptibility to neuronal oxidative stress in mice after transient cerebral ischemia. EAAC1 was first described as a glutamate transporter but later recognized to also function as a cysteine transporter in neurons. EAAC1-mediated transport of cysteine into neurons contributes to neuronal antioxidant function by providing cysteine substrates for glutathione synthesis. Here we evaluated the effects of EAAC1 gene deletion on hippocampal blood vessel disorganization after transient cerebral ischemia. EAAC1−/− female mice subjected to transient cerebral ischemia by common carotid artery occlusion for 30 min exhibited twice as much hippocampal neuronal death compared to wild-type female mice as well as increased reduction of neuronal glutathione, blood–brain barrier (BBB disruption and vessel disorganization. Pre-treatment of N-acetyl cysteine, a membrane-permeant cysteine prodrug, increased basal glutathione levels in the EAAC1−/− female mice and reduced ischemic neuronal death, BBB disruption and vessel disorganization. These findings suggest that cysteine uptake by EAAC1 is important for neuronal antioxidant function under ischemic conditions.

  10. Why do some neurons in cortex respond to information in a selective manner? Insights from artificial neural networks.

    Science.gov (United States)

    Bowers, Jeffrey S; Vankov, Ivan I; Damian, Markus F; Davis, Colin J

    2016-03-01

    Why do some neurons in hippocampus and cortex respond to information in a highly selective manner? It has been hypothesized that neurons in hippocampus encode information in a highly selective manner in order to support fast learning without catastrophic interference, and that neurons in cortex encode information in a highly selective manner in order to co-activate multiple items in short-term memory (STM) without suffering a superposition catastrophe. However, the latter hypothesis is at odds with the widespread view that neural coding in the cortex is highly distributed in order to support generalization. We report a series of simulations that characterize the conditions in which recurrent Parallel Distributed Processing (PDP) models of immediate serial can recall novel words. We found that these models learned localist codes when they succeeded in generalizing to novel words. That is, just as fast learning may explain selective coding in hippocampus, STM and generalization may help explain the existence of selective codes in cortex. PMID:26722711

  11. Curcumin modulates dopaminergic receptor, CREB and phospholipase c gene expression in the cerebral cortex and cerebellum of streptozotocin induced diabetic rats

    Directory of Open Access Journals (Sweden)

    George Naijil

    2010-05-01

    Full Text Available Abstract Curcumin, an active principle component in rhizome of Curcuma longa, has proved its merit for diabetes through its anti-oxidative and anti-inflammatory properties. This study aims at evaluating the effect of curcumin in modulating the altered dopaminergic receptors, CREB and phospholipase C in the cerebral cortex and cerebellum of STZ induced diabetic rats. Radioreceptor binding assays and gene expression was done in the cerebral cortex and cerebellum of male Wistar rats using specific ligands and probes. Total dopaminergic receptor binding parameter, Bmax showed an increase in cerebral cortex and decrease in the cerebellum of diabetic rats. Gene expression studies using real time PCR showed an increased expression of dopamine D1 and D2 receptor in the cerebral cortex of diabetic rats. In cerebellum dopamine D1 receptor was down regulated and D2 receptor showed an up regulation. Transcription factor CREB and phospholipase C showed a significant down regulation in cerebral cortex and cerebellum of diabetic rats. We report that curcumin supplementation reduces diabetes induced alteration of dopamine D1, D2 receptors, transcription factor CREB and phospholipase C to near control. Our results indicate that curcumin has a potential to regulate diabetes induced malfunctions of dopaminergic signalling, CREB and Phospholipase C expression in cerebral cortex and cerebellum and thereby improving the cognitive and emotional functions associated with these regions. Furthermore, in line with these studies an interaction between curcumin and dopaminergic receptors, CREB and phospholipase C is suggested, which attenuates the cortical and cerebellar dysfunction in diabetes. These results suggest that curcumin holds promise as an agent to prevent or treat CNS complications in diabetes.

  12. 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

  13. 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.

  14. 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.

  15. Neuropeptide S facilitates mice olfactory function through activation of cognate receptor-expressing neurons in the olfactory cortex.

    Directory of Open Access Journals (Sweden)

    Yu-Feng Shao

    Full Text Available Neuropeptide S (NPS is a newly identified neuromodulator located in the brainstem and regulates various biological functions by selectively activating the NPS receptors (NPSR. High level expression of NPSR mRNA in the olfactory cortex suggests that NPS-NPSR system might be involved in the regulation of olfactory function. The present study was undertaken to investigate the effects of intracerebroventricular (i.c.v. injection of NPS or co-injection of NPSR antagonist on the olfactory behaviors, food intake, and c-Fos expression in olfactory cortex in mice. In addition, dual-immunofluorescence was employed to identify NPS-induced Fos immunereactive (-ir neurons that also bear NPSR. NPS (0.1-1 nmol i.c.v. injection significantly reduced the latency to find the buried food, and increased olfactory differentiation of different odors and the total sniffing time spent in olfactory habituation/dishabituation tasks. NPS facilitated olfactory ability most at the dose of 0.5 nmol, which could be blocked by co-injection of 40 nmol NPSR antagonist [D-Val(5]NPS. NPS administration dose-dependently inhibited food intake in fasted mice. Ex-vivo c-Fos and NPSR immunohistochemistry in the olfactory cortex revealed that, as compared with vehicle-treated mice, NPS markedly enhanced c-Fos expression in the anterior olfactory nucleus (AON, piriform cortex (Pir, ventral tenia tecta (VTT, the anterior cortical amygdaloid nucleus (ACo and lateral entorhinal cortex (LEnt. The percentage of Fos-ir neurons that also express NPSR were 88.5% and 98.1% in the AON and Pir, respectively. The present findings demonstrated that NPS, via selective activation of the neurons bearing NPSR in the olfactory cortex, facilitates olfactory function in mice.

  16. 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.

  17. 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

  18. Scanning microscopic evaluation on the development of the cerebral cortex in embryonic mouse subjected to γ-irradiation

    International Nuclear Information System (INIS)

    Morphological events occurring in the developing cerebral hemispheres of mice exposed to a single dose of 60Co γ-irradiation 1.5 Gy on embryonic day 13 (E13) were evaluated by scanning microscope. Twenty-four hr after the exposure, both cell debris and surviving cells had poured out into the ventricular lumen. Radial glial fibers were more crumpled than in the controls. By day E15, proliferating cells in different stages of the cell cycle appeared in the ventricular zone. The glial fibers formed a network through the brain mantle. By E17 many migrating cells attached to the disorderly glial fibers appeared in the different layers of the thin cerebral mantle. These findings suggest that development of the glial fibers was interrupted as early as 24 hr after the single exposure, implying that irradiation on the developing brain may disrupt neuronal migration. (author)

  19. Hyperammonemia inhibits the natriuretic peptide receptor 2 (NPR-2)-mediated cyclic GMP synthesis in the astrocytic compartment of rat cerebral cortex slices.

    Science.gov (United States)

    Zielińska, Magdalena; Fresko, Inez; Konopacka, Agnieszka; Felipo, Vicente; Albrecht, Jan

    2007-11-01

    The decrease of cyclic GMP (cGMP) level in the brain, contributing to cognitive and memory deficit in hyperammonemia (HA), has been attributed to the interference of ammonia with the NMDA/nitric oxide/soluble guanylate cyclase (GC)/cGMP pathway in neurons. The present study tested the hypotheses that (a) HA also affects cGMP synthesis elicited by stimulation of the natriuretic peptide receptor 2 (NPR-2) with its natural ligand, C-type natriuretic peptide (CNP) and (b) the latter effect may involve astrocytes, the ammonia-sensitive cells. In the cerebral cortical slices of control rats, CNP stimulated cGMP synthesis in a degree comparable to the NO donor, S-nitroso-N-acetylpenicillamine (SNAP) used at an optimal concentration. Fluoroacetate (FA), a metabolic inhibitor specifically affecting astrocytic mitochondria, inhibited the CNP-dependent cGMP synthesis by about 50%. Ammonium acetate-induced HA decreased by 68% the CNP-dependent cGMP generation in slices incubated in the absence of FA. In slices incubated in the presence of FA, cGMP synthesis in slices derived from HA rats did not differ from that in control slices. The results indicate that HA inhibits CNP-dependent cGMP synthesis in the FA-vulnerable, astrocytic compartment, but not in the FA-resistant compartment(s) of the brain. HA did not affect the expression of NPR-2 mRNA in the cerebral cortex tissue as tested using real-time PCR, indicating that the effect of ammonia involves as yet unidentified events occurring posttranscriptionally. Deregulation of NPR-2 function in astrocytes by ammonia may contribute to neurophysiological symptoms of HA. PMID:17629948

  20. Hypoglycemic neuronal death is triggered by glucose reperfusion and activation of neuronal NADPH oxidase

    OpenAIRE

    Suh, Sang Won; Gum, Elizabeth T.; Hamby, Aaron M.; Chan, Pak H.; Swanson, Raymond A

    2007-01-01

    Hypoglycemic coma and brain injury are potential complications of insulin therapy. Certain neurons in the hippocampus and cerebral cortex are uniquely vulnerable to hypoglycemic cell death, and oxidative stress is a key event in this cell death process. Here we show that hypoglycemia-induced oxidative stress and neuronal death are attributable primarily to the activation of neuronal NADPH oxidase during glucose reperfusion. Superoxide production and neuronal death were blocked by the NADPH ox...

  1. 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.

  2. 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...

  3. 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

  4. 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

  5. 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.

  6. 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.

  7. 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

  8. 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.

  9. 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.

  10. 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

  11. Deep layer neurons in the rat medial entorhinal cortex fire sparsely irrespective of spatial novelty

    Directory of Open Access Journals (Sweden)

    Andrea Burgalossi

    2014-07-01

    Full Text Available Extracellular recordings in medial entorhinal cortex have revealed the existence of spatially-modulated firing patterns, which are thought to contribute to a cognitive map of external space. Previous work indicated that during exploration of novel environments, spiking activity in deep entorhinal layers is much sparser than in superficial layers. In the present report, we ask whether this laminar activity profile is a consequence of environmental novelty. We report on a large dataset of juxtacellularly-recorded neurons (n = 70 whose spiking activity was monitored while rats explored either a novel or a familiar environment, or both within the same session. Irrespective of previous knowledge of the environment, deep layer activity was very low during exploration (median firing rate 0.4 Hz for non-silent cells, with a large fraction of silent cells (n = 19 of a total 37, while superficial layer activity was several times higher (median firing rate 2.4 Hz; n = 33. The persistence of laminar differences in firing activity both under environmental novelty and familiarity, and even in head-restrained stationary animals, suggests that sparse coding might be a constitutive feature of deep entorhinal layers.

  12. Neuronal and inducible nitric oxide synthase upregulation in the rat medial prefrontal cortex following acute restraint stress: A dataset.

    Science.gov (United States)

    Spiers, Jereme G; Chen, Hsiao-Jou Cortina; Lee, Johnny K; Sernia, Conrad; Lavidis, Nickolas A

    2016-03-01

    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]. PMID:26909371

  13. Quantitative histological studies on aging changes in cerebral cortex of rhesus monkey and albino rat with notes on effects of prolonged low-dose ionizing irradiation in the rat

    International Nuclear Information System (INIS)

    Brains of a series of eight young adult control (150 days) and eight middle-aged control (550 days) rats were fixed by a two-stage perfusion procedure employing Heidenhain's 'susa' solution. An equal number of rats were exposed to γ-irradiation at 6.5 R/day beginning on the 50th postnatal day and were sacrificed in the same manner and at the same age levels as the previous group. Paraffin sections were cut at 20 and 6 μ from cerebral cortical area 3 in the rat brains. Sections used for cell counts were stained with Harris' hematoxylin and eosin or iron hematoxylin, gallocyanin, acid fuchsin and ponceau de xylidene. Counts of neurons and glia were carried out at 20 equally spaced submolecular depth levels, and cell frequency profiles were plotted for each of the two cell types. The mean neuron and glial packing density for the total depth of the submolecular cortex of area 3 was not significantly different in young adult and middle-aged controls or in young adult irradiated (total dose 650 R) and control animals. However, statistical evaluation of data for relative depth levels 7 through 20 indicated that the packing density in this zone was significantly less (P<0.02) in middle-aged controls than in young adult animals. In middle-aged irradiated rats (total dose about 3250 R) neuron and glial packing densities for total depth of submolecular cortex were not significantly different than in control animals at the same age level. However, the values obtained for neuron packing density at relative depth levels 1 through 8 were significantly lower in middle-aged irradiated than in middle-aged control rats. The neuron packing density in middle-aged irradiated rats was significantly lower than in the young adult irradiated males. In electron micrographs, an increase in the amount of glycogen granules in astrocyte cell processes in cerebral cortex of irradiated middle-aged rats was noted, but there was no evidence of any other ultrastructural alterations

  14. 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...

  15. 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=...

  16. 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

  17. 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.

  18. 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.

  19. Species-Dependent Post-Transcriptional Regulation of NOS1 by FMRP in the Developing Cerebral Cortex

    Science.gov (United States)

    Kwan, Kenneth Y.; Lam, Mandy M. S.; Johnson, Matthew B.; Dube, Umber; Shim, Sungbo; Rašin, Mladen-Roko; Sousa, André M. M.; Fertuzinhos, Sofia; Chen, Jie-Guang; Arellano, Jon I.; Chan, Daniel W.; Pletikos, Mihovil; Vasung, Lana; Rowitch, David H.; Huang, Eric J.; Schwartz, Michael L.; Willemsen, Rob; Oostra, Ben A.; Rakic, Pasko; Heffer, Marija; Kostović, Ivica; Judaš, Milos; Šestan, Nenad

    2012-01-01

    SUMMARY Fragile X syndrome (FXS), the leading monogenic cause of intellectual disability and autism, results from loss of function of the RNA-binding protein FMRP. Here we show that FMRP regulates the translation of neuronal nitric oxide synthase 1 (NOS1) in the developing human neocortex. Whereas NOS1 mRNA is ubiquitously expressed, NOS1 protein is transiently co-expressed with FMRP during early synaptogenesis in layer- and region-specific subpopulations of pyramidal neurons. These include mid-fetal layer 5 subcortically projecting neurons arranged into alternating columns in the prospective Broca’s area and orofacial motor cortex. Human NOS1 translation is activated by FMRP via interactions with coding region binding motifs absent from mouse Nos1 mRNA, which is expressed in mouse pyramidal neurons, but not efficiently translated. Correspondingly, neocortical NOS1 protein levels are severely reduced in developing human FXS cases but not FMRP-deficient mice. Thus, alterations in FMRP post-transcriptional regulation of NOS1 in developing neocortical circuits may contribute to cognitive dysfunction in FXS. PMID:22579290

  20. 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

  1. Antioxidant Activity of Grapevine Leaf Extracts against Oxidative Stress Induced by Carbon Tetrachloride in Cerebral Cortex, Hippocampus and Cerebellum of Rats

    Science.gov (United States)

    Wohlenberg, Mariane; Almeida, Daniela; Bokowski, Liane; Medeiros, Niara; Agostini, Fabiana; Funchal, Cláudia; Dani, Caroline

    2014-01-01

    In recent years, it has become increasingly important to study the beneficial properties of derivatives of grapes and grapevine. The objective of this study was to determine the antioxidant activity of Vitis labrusca leaf extracts, comparing conventional and organic grapevines, in different brain areas of rats. We used male Wistar rats treated with grapevine leaf extracts for a period of 14 days, and on the 15th day, we administered in half of the rats, mineral oil and the other half, carbon tetrachloride (CCl4). The animals were euthanized by decapitation and the cerebral cortex, hippocampus and cerebellum were removed to assess oxidative stress parameters and the activity of antioxidant enzymes. Lipid peroxidation levels (TBARS) were unchanged. However, CCl4 induced oxidative damage to proteins in all tissues studied, and this injury was prevented by both extracts. Superoxide dismutase (SOD) activity was increased by CCl4 in the cerebral cortex and decreased in other tissues. However, CCl4 increased catalase (CAT) activity in the cerebellum and decreased it in the cerebral cortex. The SOD/CAT ratio was restored in the cerebellum by both extracts and only in the cerebral cortex by the organic extract. PMID:26784867

  2. Antioxidant Activity of Grapevine Leaf Extracts against Oxidative Stress Induced by Carbon Tetrachloride in Cerebral Cortex, Hippocampus and Cerebellum of Rats

    Directory of Open Access Journals (Sweden)

    Mariane Wohlenberg

    2014-04-01

    Full Text Available In recent years, it has become increasingly important to study the beneficial properties of derivatives of grapes and grapevine. The objective of this study was to determine the antioxidant activity of Vitis labrusca leaf extracts, comparing conventional and organic grapevines, in different brain areas of rats. We used male Wistar rats treated with grapevine leaf extracts for a period of 14 days, and on the 15th day, we administered in half of the rats, mineral oil and the other half, carbon tetrachloride (CCl4. The animals were euthanized by decapitation and the cerebral cortex, hippocampus and cerebellum were removed to assess oxidative stress parameters and the activity of antioxidant enzymes. Lipid peroxidation levels (TBARS were unchanged. However, CCl4 induced oxidative damage to proteins in all tissues studied, and this injury was prevented by both extracts. Superoxide dismutase (SOD activity was increased by CCl4 in the cerebral cortex and decreased in other tissues. However, CCl4 increased catalase (CAT activity in the cerebellum and decreased it in the cerebral cortex. The SOD/CAT ratio was restored in the cerebellum by both extracts and only in the cerebral cortex by the organic extract.

  3. Wernicke's encephalopathy induced by total parenteral nutrition in patient with acute leukaemia: unusual involvement of caudate nuclei and cerebral cortex on MRI

    International Nuclear Information System (INIS)

    We report a 13-year-old girl with leukaemia and Wernicke's encephalopathy induced by total parenteral nutrition. MRI showed unusual bilateral lesions of the caudate nuclei and cerebral cortex, as well as typical lesions surrounding the third ventricle and aqueduct. After intravenous thiamine, the patient improved, and the abnormalities on MRI disappeared. (orig.)

  4. 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

  5. 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

  6. 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

  7. 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.

  8. An interspecies comparison of mercury inhibition on muscarinic acetylcholine receptor binding in the cerebral cortex and cerebellum

    International Nuclear Information System (INIS)

    Mercury (Hg) is a ubiquitous pollutant that can disrupt neurochemical signaling pathways in mammals. It is well documented that inorganic Hg (HgCl2) and methyl Hg (MeHg) can inhibit the binding of radioligands to the muscarinic acetylcholine (mACh) receptor in rat brains. However, little is known concerning this relationship in specific anatomical regions of the brain or in other species, including humans. The purpose of this study was to explore the inhibitory effects of HgCl2 and MeHg on [3H]-quinuclidinyl benzilate ([3H]-QNB) binding to the mACh receptor in the cerebellum and cerebral cortex regions from human, rat, mouse, mink, and river otter brain tissues. Saturation binding curves were obtained from each sample to calculate receptor density (B max) and ligand affinity (K d). Subsequently, samples were exposed to HgCl2 or MeHg to derive IC50 values and inhibition constants (K i). Results demonstrate that HgCl2 is a more potent inhibitor of mACh receptor binding than MeHg, and the receptors in the cerebellum are more sensitive to Hg-mediated mACh receptor inhibition than those in the cerebral cortex. Species sensitivities, irrespective of Hg type and brain region, can be ranked from most to least sensitive: river otter > rat > mink > mouse > humans. In summary, our data demonstrate that Hg can inhibit the binding [3H]-QNB to the mACh receptor in a range of mammalian species. This comparative study provides data on interspecies differences and a framework for interpreting results from human, murine, and wildlife studies

  9. Primary motor cortex neurons classified in a postural task predict muscle activation patterns in a reaching task.

    Science.gov (United States)

    Heming, Ethan A; Lillicrap, Timothy P; Omrani, Mohsen; Herter, Troy M; Pruszynski, J Andrew; Scott, Stephen H

    2016-04-01

    Primary motor cortex (M1) activity correlates with many motor variables, making it difficult to demonstrate how it participates in motor control. We developed a two-stage process to separate the process of classifying the motor field of M1 neurons from the process of predicting the spatiotemporal patterns of its motor field during reaching. We tested our approach with a neural network model that controlled a two-joint arm to show the statistical relationship between network connectivity and neural activity across different motor tasks. In rhesus monkeys, M1 neurons classified by this method showed preferred reaching directions similar to their associated muscle groups. Importantly, the neural population signals predicted the spatiotemporal dynamics of their associated muscle groups, although a subgroup of atypical neurons reversed their directional preference, suggesting a selective role in antagonist control. These results highlight that M1 provides important details on the spatiotemporal patterns of muscle activity during motor skills such as reaching. PMID:26843605

  10. Neuronal activity in primate dorsal anterior cingulate cortex signals task conflict and predicts adjustments in pupil-linked arousal

    Science.gov (United States)

    Ebitz, R. Becket; Platt, Michael L.

    2014-01-01

    Summary Whether driving a car, shopping for food, or paying attention in a classroom of boisterous teenagers, it’s often hard to maintain focus on goals in the face of distraction. Brain imaging studies in humans implicate the dorsal anterior cingulate cortex (dACC) in regulating the conflict between goals and distractors. Here we show for the first time that single dACC neurons signal conflict between task goals and distractors in the rhesus macaque, particularly for biologically-relevant social stimuli. For some neurons, task conflict signals predicted subsequent changes in pupil size—a peripheral index of arousal linked to noradrenergic tone—associated with reduced distractor interference. dACC neurons also responded to errors and these signals predicted adjustments in pupil size. These findings provide the first neurophysiological endorsement of the hypothesis that dACC regulates conflict, in part, via modulation of pupil-linked processes such as arousal. PMID:25654259

  11. 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

  12. 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.

  13. [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

  14. 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. PMID

  15. 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...

  16. Are both embryonic migratory pathways preserved in the adult brain cerebral cortex?

    Czech Academy of Sciences Publication Activity Database

    Šimonová, Zuzana; Dutt, James

    2006-01-01

    Roč. 107, č. 1 (2006), s. 71-80. ISSN 1214-6994 Institutional research plan: CEZ:AV0Z50390512 Keywords : Migratio * Neuronal progenitors * Rostral migratory stream Subject RIV: EB - Genetics ; Molecular Biology

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. Cerebral responses and role of the prefrontal cortex in conditioned pain modulation: an fMRI study in healthy subjects.

    Science.gov (United States)

    Bogdanov, Volodymyr B; Viganò, Alessandro; Noirhomme, Quentin; Bogdanova, Olena V; Guy, Nathalie; Laureys, Steven; Renshaw, Perry F; Dallel, Radhouane; Phillips, Christophe; Schoenen, Jean

    2015-03-15

    The mechanisms underlying conditioned pain modulation (CPM) are multifaceted. We searched for a link between individual differences in prefrontal cortex activity during multi-trial heterotopic noxious cold conditioning and modulation of the cerebral response to phasic heat pain. In 24 healthy female subjects, we conditioned laser heat stimuli to the left hand by applying alternatively ice-cold or lukewarm compresses to the right foot. We compared pain ratings with cerebral fMRI BOLD responses. We also analyzed the relation between CPM and BOLD changes produced by the heterotopic cold conditioning itself, as well as the impact of anxiety and habituation of cold-pain ratings. Specific cerebral activation was identified in precuneus and left posterior insula/SII, respectively, during early and sustained phases of cold application. During cold conditioning, laser pain decreased (n=7), increased (n=10) or stayed unchanged (n=7). At the individual level, the psychophysical effect was directly proportional to the cold-induced modulation of the laser-induced BOLD response in left posterior insula/SII. The latter correlated with the BOLD response recorded 80s earlier during the initial 10-s phase of cold application in anterior cingulate, orbitofrontal and lateral prefrontal cortices. High anxiety and habituation of cold pain were associated with greater laser heat-induced pain during heterotopic cold stimulation. The habituation was also linked to the early cold-induced orbitofrontal responses. We conclude that individual differences in conditioned pain modulation are related to different levels of prefrontal cortical activation by the early part of the conditioning stimulus, possibly due to different levels in trait anxiety. PMID:25461267

  2. Secretory function in subplate neurons during cortical development

    OpenAIRE

    Kondo, Shinichi; Al-Hasani, Hannah; Hoerder-Suabedissen, Anna; Wang, Wei Zhi; Molnár, Zoltán

    2015-01-01

    Subplate cells are among the first generated neurons in the mammalian cerebral cortex and have been implicated in the establishment of cortical wiring. In rodents some subplate neurons persist into adulthood. Here we would like to highlight several converging findings which suggest a novel secretory function of subplate neurons during cortical development. Throughout the postnatal period in rodents, subplate neurons have highly developed rough endoplasmic reticulum (ER) and are under an ER st...

  3. 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.

  4. 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...

  5. The mode of synaptic activation of pyramidal neurons in the cat primary somatosensory cortex: an intracellular HRP study.

    Science.gov (United States)

    Yamamoto, T; Samejima, A; Oka, H

    1990-01-01

    A total of 141 pyramidal neurons in the cat primary somatosensory cortex (SI) were recorded intracellularly under Nembutal anesthesia (7 in layer II, 43 in layer III, 8 in layer IV, 58 in layer V and 25 in layer VI). Most neurons were identified by intracellular staining with HRP, though some layer V pyramidal neurons were identified only electrophysiologically with antidromic activation of medullary pyramid (PT) or pontine nuclear (PN) stimulation. Excitatory synaptic potentials (EPSPs) were analyzed with stimulation of the superficial radial nerve (SR), the ventral posterolateral nucleus (VPL) in the thalamus and the thalamic radiation (WM). The pyramidal neurons in layers III and IV received EPSPs at the shortest latency: 9.1 +/- 2.1 ms (Mean +/- S.D.) for SR and 1.6 +/- 0.7 ms for VPL stimulation. Layer II pyramidal neurons also responded at a short latency to VPL stimulation (1.7 +/- 0.5 ms), though their mean latencies for SR-induced EPSPs were relatively longer (10.6 +/- 1.9 ms). The mean latencies were much longer in layers V and VI pyramidal neurons (10.2 +/- 2.4 ms and 2.9 +/- 1.5 ms in layer V pyramidal neurons and 9.9 +/- 2.5 ms and 2.8 +/- 1.6 ms in layer VI pyramidal ones, respectively for SR and VPL stimulation). The comparison of the latencies between VPL and WM stimulation indicates that most layer III-IV pyramidal neurons and some pyramidal cells in layers II, V and VI received monosynaptic inputs from VPL. These findings are consistent with morphological data on the laminar distribution of thalamocortical fibers, i.e., thalamocortical fibers terminate mainly in the deeper part of layers III and IV with some collaterals in layers V, VI and II-I. The time-sequences of the latencies of VPL-EPSPs indicate that corticocortical and/or transcallosal neurons (pyramidal neurons in layers II and III) fire first and are followed by firing of the output neurons projecting to the subcortical structures (pyramidal neurons in layers V and VI). PMID:2358022

  6. Reorganization of Human Cerebral Cortex : the Range of Changes following Use and Injury

    OpenAIRE

    Elbert, Thomas; Rockstroh, Brigitte

    2004-01-01

    Animal and human research over the past decades have increasingly detailed the brain s capacity for reorganization of neural network architecture to adapt to environmental needs. In this article, the authors outline the range of reorganization of human representational cortex, encompassing reconstruction in concurrence with enhanced behaviorally relevant afferent activity (examples include skilled musicians and blind Braille readers); injury-related response dynamics as, for instance, driven ...

  7. 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.

  8. 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

  9. Function and Regulation of Bone Morphogenetic Protein 7 (BMP7) in Cerebral Cortex Development

    OpenAIRE

    Ortega Cano, Juan Alberto

    2011-01-01

    [eng] Brain derived neurotrophic factor (BDNF) is a chemokine which levels are regulated by neuronal activity and could act as a sensor in front of distinct physiologic stimulus, activating the transcription of specific group of genes. In this work we show that BDNF induces the expression of BMP7 in neurons through TrkB receptor and MAPK/ERK pathways, an induction mechanism that is mediated in part by the release of the transcriptional repression exerted by p53 family proteins. BMP member...

  10. 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 ...

  11. Temporal encoding precision of bat auditory neurons tuned to target distance deteriorates on the way to the cortex.

    Science.gov (United States)

    Macías, Silvio; Hechavarría, Julio C; Kössl, Manfred

    2016-03-01

    During echolocation, bats estimate distance to avoid obstacles and capture moving prey. The primary distance cue is the delay between the bat's emitted echolocation pulse and the return of an echo. In the bat's auditory system, echo delay-tuned neurons that only respond to pulse-echo pairs having a specific echo delay serve target distance calculation. Accurate prey localization should benefit from the spike precision in such neurons. Here we show that delay-tuned neurons in the inferior colliculus of the mustached bat respond with higher temporal precision, shorter latency and shorter response duration than those of the auditory cortex. Based on these characteristics, we suggest that collicular neurons are best suited for a fast and accurate response that could lead to fast behavioral reactions while cortical neurons, with coarser temporal precision and longer latencies and response durations could be more appropriate for integrating acoustic information over time. The latter could be important for the formation of biosonar images. PMID:26785850

  12. 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

  13. 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…

  14. 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...

  15. Angiotensin II type-2 receptor stimulation induces neuronal VEGF synthesis after cerebral ischemia.

    Science.gov (United States)

    Mateos, Laura; Perez-Alvarez, Maria Jose; Wandosell, Francisco

    2016-07-01

    Intense efforts are being undertaken to understand the pathobiology of ischemia and to develop novel and effective treatments. Angiotensin II type 2 receptor (AT2R) is related with a beneficial role in neurodegenerative disorders, including ischemia. However, the underlying molecular mechanism remains elusive. In this study, we have established that AT2R stimulation by C21 compound, a specific AT2R agonist, caused a VEGF upregulation. Using mouse primary cortical neurons exposed to oxygen-glucose deprivation (OGD), we established that this effect was mediated by a mechanism dependent of mTORC1 signaling since mTOR inhibition abolished the C21-induced VEGF upregulation. Also, we have temporally characterized the changes on VEGF levels after ischemia induction in rats using two different approaches: transient and permanent middle cerebral artery occlusion (tMCAO and pMCAO). VEGF levels were permanently augmented after reperfusion (tMCAO) whereas lower levels of VEGF were found after pMCAO, remarkably at 21days. Therefore, C21 compound accelerated the recovery of the neurological status of pMCAO rats, reduced the ischemic damage area and abolished pMCAO-induced VEGF downregulation at 21days. This effect of C21 compound was mainly observed in neurons of the peri-infarct area. Our results suggest that a C21-induced VEGF upregulation may be crucial after an ischemic neuronal insult in both of our experimental approaches. This upregulation was mediated by a mechanism dependent of Akt/mTOR signaling pathway, since mTOR inhibition abolished the VEGF upregulation induced by C21. Considering that VEGF is involved in regenerative processes, we propose that AT2R activation could be used as a potential pharmacological strategy after ischemic stroke. PMID:27045356

  16. 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

  17. 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

  18. The Neuron-Astrocyte-Microglia Triad in a Rat Model of Chronic Cerebral Hypoperfusion: Protective Effect of Dipyridamole

    Directory of Open Access Journals (Sweden)

    Daniele Lana

    2014-11-01

    Full Text Available Chronic cerebral hypoperfusion during aging may cause progressive neurodegeneration as ischemic conditions persist. Proper functioning of the interplay between neurons and glia is fundamental for the functional organization of the brain. The aim of our research was to study the pathophysiological mechanisms, and particularly the derangement of the interplay between neurons and astrocytes-microglia with the formation of “triads”, in a model of chronic cerebral hypoperfusion induced by the 2-vessel occlusion (2VO in adult Wistar rats (n=15. The protective effect of dipyridamole given during the early phases after 2VO (4 mg/kg/day i.v., the first 7 days after 2VO was verified (n=15. Sham-operated rats (n=15 were used as controls. Immunofluorescent triple staining of neurons (NeuN, astrocytes (GFAP and microglia (IBA1 was performed 90 days after 2VO. We found significantly higher amount of “ectopic” neurons, neuronal debris and apoptotic neurons in CA1 Str. Radiatum and Str. Pyramidale of 2VO rats. In CA1 Str. Radiatum of 2VO rats the amount of astrocytes (cells/mm2 did not increase. In some instances several astrocytes surrounded ectopic neurons and formed a “micro scar” around them. Astrocyte branches could infiltrate the cell body of ectopic neurons, and, together with activated microglia cells formed the “triads”. In the triad, significantly more numerous in CA1 Str. Radiatum of 2VO than in sham rats, astrocytes and microglia cooperated in the phagocytosis of ectopic neurons. These events might be common mechanisms underlying many neurodegenerative processes. The frequency to which they appear might depend upon, or might be the cause of, the burden and severity of neurodegeneration. Dypiridamole significantly reverted all the above described events. The protective effect of chronic administration of dipyridamole might be a consequence of its vasodilatory, antioxidant and anti-inflammatory role during the early phases after 2VO.

  19. Differential contribution of TRPM4 and TRPM5 nonselective cation channels to the slow afterdepolarization in mouse prefrontal cortex neurons

    Science.gov (United States)

    Lei, Ya-Ting; Thuault, Sebastien J.; Launay, Pierre; Margolskee, Robert F.; Kandel, Eric R.; Siegelbaum, Steven A.

    2014-01-01

    In certain neurons from different brain regions, a brief burst of action potentials can activate a slow afterdepolarization (sADP) in the presence of muscarinic acetylcholine receptor agonists. The sADP, if suprathreshold, can contribute to persistent non-accommodating firing in some of these neurons. Previous studies have characterized a Ca2+-activated non-selective cation (CAN) current (ICAN) that is thought to underlie the sADP. ICAN depends on muscarinic receptor stimulation and exhibits a dependence on neuronal activity, membrane depolarization and Ca2+-influx similar to that observed for the sADP. Despite the widespread occurrence of sADPs in neurons throughout the brain, the molecular identity of the ion channels underlying these events, as well as ICAN, remains uncertain. Here we used a combination of genetic, pharmacological and electrophysiological approaches to characterize the molecular mechanisms underlying the muscarinic receptor-dependent sADP in layer 5 pyramidal neurons of mouse prefrontal cortex. First, we confirmed that in the presence of the cholinergic agonist carbachol a brief burst of action potentials triggers a prominent sADP in these neurons. Second, we confirmed that this sADP requires activation of a PLC signaling cascade and intracellular calcium signaling. Third, we obtained direct evidence that the transient receptor potential (TRP) melastatin 5 channel (TRPM5), which is thought to function as a CAN channel in non-neural cells, contributes importantly to the sADP in the layer 5 neurons. In contrast, the closely related TRPM4 channel may play only a minor role in the sADP. PMID:25237295

  20. Differential contribution of TRPM4 and TRPM5 nonselective cation channels to the slow afterdepolarization in mouse prefrontal cortex neurons

    Directory of Open Access Journals (Sweden)

    Pierre Launay

    2014-09-01

    Full Text Available In certain neurons from different brain regions, a brief burst of action potentials can activate a slow afterdepolarization (sADP in the presence of muscarinic acetylcholine receptor agonists. The sADP, if suprathreshold, can contribute to persistent non-accommodating firing in some of these neurons. Previous studies have characterized a Ca2+-activated non-selective cation (CAN current (ICAN that is thought to underlie the sADP. ICAN depends on muscarinic receptor stimulation and exhibits a dependence on neuronal activity, membrane depolarization and Ca2+-influx similar to that observed for the sADP. Despite the widespread occurrence of sADPs in neurons throughout the brain, the molecular identity of the ion channels underlying these events, as well as ICAN, remains uncertain. Here we used a combination of genetic, pharmacological and electrophysiological approaches to characterize the molecular mechanisms underlying the muscarinic receptor-dependent sADP in layer 5 pyramidal neurons of mouse prefrontal cortex. First, we confirmed that in the presence of the cholinergic agonist carbachol a brief burst of action potentials triggers a prominent sADP in these neurons. Second, we confirmed that this sADP requires activation of a PLC signaling cascade and intracellular calcium signaling. Third, we obtained direct evidence that the transient receptor potential melastatin 5 channel (TRPM5, which is thought to function as a CAN channel in non-neural cells, contributes importantly to the sADP in the layer 5 neurons. In contrast, the closely related TRPM4 channel may play only a minor role in the sADP.

  1. 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...

  2. Choline acetyltransferase-containing neurons in the human parietal neocortex

    Directory of Open Access Journals (Sweden)

    V Benagiano

    2009-06-01

    Full Text Available A number of immunocytochemical studies have indicated the presence of cholinergic neurons in the cerebral cortex of various species of mammals. Whether such cholinergic neurons in the human cerebral cortex are exclusively of subcortical origin is still debated. In this immunocytochemical study, the existence of cortical cholinergic neurons was investigated on surgical samples of human parietal association neocortex using a highly specific monoclonal antibody against choline acetyltransferase (ChAT, the acetylcholine biosynthesising enzyme. ChAT immunoreactivity was detected in a subpopulation of neurons located in layers II and III. These were small or medium-sized pyramidal neurons which showed cytoplasmic immunoreactivity in the perikarya and processes, often in close association to blood microvessels. This study, providing demonstration of ChAT neurons in the human parietal neocortex, strongly supports the existence of intrinsic cholinergic innervation of the human neocortex. It is likely that these neurons contribute to the cholinergic innervation of the intracortical microvessels.

  3. Cyclooxygenase 2 and neuronal nitric oxide synthase expression in the renal cortex are not interdependent in states of salt deficiency

    DEFF Research Database (Denmark)

    Castrop, H; Kammerl, M; Mann, Birgitte;

    2000-01-01

    Neuronal nitric oxide synthase (nNOS) and cyclooxygenase-2 (COX-2) expression in the kidney are localized to the cortical thick ascending limb of the loop of Henle (cTALH), including the macula region, and increase after salt restriction. Because of the similar localization and regulation of n...... prostanoid excretion. These findings suggest that under these conditions the control of nNOS and COX-2 gene expression in the macula densa regions of the kidney cortex are not dependent on each other....

  4. Region-specific maturation of cerebral cortex in human fetal brain: diffusion tensor imaging and histology

    International Nuclear Information System (INIS)

    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.)

  5. 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

  6. 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.)

  7. Auditory Cortex Basal Activity Modulates Cochlear Responses in Chinchillas

    OpenAIRE

    León, Alex; Elgueda, Diego; Silva, María A.; Hamamé, Carlos M.; Delano, Paul H.

    2012-01-01

    Background The auditory efferent system has unique neuroanatomical pathways that connect the cerebral cortex with sensory receptor cells. Pyramidal neurons located in layers V and VI of the primary auditory cortex constitute descending projections to the thalamus, inferior colliculus, and even directly to the superior olivary complex and to the cochlear nucleus. Efferent pathways are connected to the cochlear receptor by the olivocochlear system, which innervates outer hair cells and auditory...

  8. [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

  9. Accumulation of Filamentous Tau in the Cerebral Cortex of Human Tau R406W Transgenic Mice

    OpenAIRE

    Ikeda, Masaki; Shoji†, Mikio; Kawarai, Toshitaka; Kawarabayashi, Takeshi; Matsubara, Etsuro; Murakami, Tetsuro; Sasaki, Atsushi; Tomidokoro, Yasushi; Ikarashi, Yasushi; Kuribara, Hisashi; Ishiguro, Koichi; Hasegawa, Masato; Yen, Shu-Hui; Chishti, M. Azhar; Harigaya, Yasuo

    2005-01-01

    Missense mutations of the tau gene cause autosomal dominant frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17), an illness characterized by progressive personality changes, dementia, and parkinsonism. There is prominent frontotemporal lobe atrophy of the brain accompanied by abundant tau accumulation with neurofibrillary tangles and neuronal cell loss. Using a hamster prion protein gene expression vector, we generated several independent lines of transgenic (Tg) mice e...

  10. 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...

  11. Optimizing sound features for cortical neurons.

    Science.gov (United States)

    deCharms, R C; Blake, D T; Merzenich, M M

    1998-05-29

    The brain's cerebral cortex decomposes visual images into information about oriented edges, direction and velocity information, and color. How does the cortex decompose perceived sounds? A reverse correlation technique demonstrates that neurons in the primary auditory cortex of the awake primate have complex patterns of sound-feature selectivity that indicate sensitivity to stimulus edges in frequency or in time, stimulus transitions in frequency or intensity, and feature conjunctions. This allows the creation of classes of stimuli matched to the processing characteristics of auditory cortical neurons. Stimuli designed for a particular neuron's preferred feature pattern can drive that neuron with higher sustained firing rates than have typically been recorded with simple stimuli. These data suggest that the cortex decomposes an auditory scene into component parts using a feature-processing system reminiscent of that used for the cortical decomposition of visual images. PMID:9603734

  12. Prenatal carbon monoxide impairs migration of interneurons into the cerebral cortex.

    Science.gov (United States)

    Trentini, John F; O'Neill, J Timothy; Poluch, Sylvie; Juliano, Sharon L

    2016-03-01

    Prenatal exposure to carbon monoxide (CO) disrupts brain development, however little is known about effects on neocortical maturation. We exposed pregnant mice to CO from embryonic day 7 (E7) until birth. To study the effect of CO on neuronal migration into the neocortex we injected BrdU during corticogenesis and observed misplaced BrdU+ cells. The majority of cells not in their proper layer colocalized with GAD65/67, suggesting impairment of interneuron migration; interneuron subtypes were also affected. We subsequently followed interneuron migration from E15 organotypic cultures of mouse neocortex exposed to CO; the leading process length of migrating neurons diminished. To examine an underlying mechanism, we assessed the effects of CO on the cellular cascade mediating the cytoskeletal protein vasodilator-stimulated phosphoprotein (VASP). CO exposure resulted in decreased cGMP and in a downstream target, phosphorylated VASP. Organotypic cultures grown in the presence of the phosphodiesterase inhibitor IBMX resulted in a recovery of the leading processes. These data support the idea that CO acts as a signaling molecule and impairs function and neuronal migration by acting through the CO/NO-cGMP pathway. In addition, treated mice demonstrated functional impairment in behavioral tests. PMID:26582457

  13. 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.)

  14. 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.

  15. 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.

  16. Quantified regional and laminar distribution of the noradrenaline innervation in the anterior half of the adult rat cerebral cortex

    International Nuclear Information System (INIS)

    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

  17. 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

  18. 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

  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)

    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

  20. 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.

  1. 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

  2. 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...

  3. Effects of exercise after focal cerebral cortex infarction on basal ganglion.

    Science.gov (United States)

    Mizutani, Kenmei; Sonoda, Shigeru; Karasawa, Nobuyuki; Yamada, Keiki; Shimpo, Kan; Chihara, Takeshi; Takeuchi, Terumi; Hasegawa, Yoko; Kubo, Kin-Ya

    2013-06-01

    Identification of functional molecules in the brain related to improvement of motor dysfunction after stroke will contribute to establish a new treatment strategy for stroke rehabilitation. Hence, monoamine changes in basal ganglion related to motor control were examined in groups with/without voluntary exercise after cerebral infarction. Cerebral infarction was produced by photothrombosis in rats. Voluntary exercise using a running wheel was initiated from 2 days after surgery. Motor performance was measured by the accelerated rotarod test. Monoamine concentrations in striatum were analyzed using HPLC and immunohistochemical staining performed with anti-tyrosine hydroxylase antibody. In behavioral evaluation, the mean latency until falling from the rotating rod in the group with exercise (infarction-EX group) was significantly longer than that in the group without exercise (infarction-CNT group). When concerning the alteration of monoamine concentration between before and 2 days after infarction, dopamine level showed a significant increase 2 days after infarction. Subsequently, dopamine level was significantly decreased in the infarction-EX group at 10 days after infarction; in contrast, both norepinephrine and 5-HT concentrations were significantly higher in the infarction-EX group than in the infarction-CNT group. Furthermore, duration of rotarod test showed a significant inverse correlation with dopamine levels and a significant positive correlation with 5-HT levels. In immunohistochemical analysis, tyrosine hydroxylase immunoreactivity in substantia nigra pars compacta was shown to increase in the infarction-CNT group. In the present study, at least some of the alterations of monoamines associated with the improvement of paralysis in the basal ganglion related to motor control might have been detected. PMID:22718437

  4. 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...

  5. 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.

  6. 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...

  7. G-protein activity in Percoll-purified plasma membranes, bulk plasma membranes, and low-density plasma membranes isolated from rat cerebral cortex

    Czech Academy of Sciences Publication Activity Database

    Bouřová, Lenka; Stöhr, Jiří; Lisý, Václav; Rudajev, Vladimír; Novotný, Jiří; Svoboda, Petr

    2009-01-01

    Roč. 15, č. 4 (2009), BR111-BR122. ISSN 1234-1010 R&D Projects: GA MŠk(CZ) LC554; GA MŠk(CZ) LC06063; GA ČR(CZ) GA309/06/0121; GA AV ČR(CZ) IAA500110606 Institutional research plan: CEZ:AV0Z50110509 Keywords : rat cerebral cortex * plasma membrane * G-protein activity Subject RIV: CE - Biochemistry Impact factor: 1.543, year: 2009

  8. 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...

  9. 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 ...

  10. 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 ...

  11. 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...

  12. 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 ...

  13. Ischemic Postconditioning Alleviates Neuronal Injury Caused by Relief of Carotid Stenosis in a Rat Model of Cerebral Hypoperfusion

    OpenAIRE

    Pengfei Ge; Yinan Luo; Boyu Wang; Tianfei Luo; Li Qi; Chunsheng Feng

    2012-01-01

    The effects of early relief of heavy bilateral carotid stenosis and ischemic postconditioning on hippocampus CA1 neurons are still unclear. In this study, we used a rat model to imitate severe bilateral carotid stenosis in humans. The rats were divided into sham group, carotid stenosis group, stenosis relief group and ischemic postconditioning group. Ischemic postconditioning consisted of three cycles of 30 s ischemia and 30 s reperfusion. The cerebral blood flow was measured with a laser Dop...

  14. The direct pathway from the brainstem reticular formation to the cerebral cortex in the ascending reticular activating system: A diffusion tensor imaging study.

    Science.gov (United States)

    Jang, Sung Ho; Kwon, Hyeok Gyu

    2015-10-01

    Precise evaluation of the ascending reticular activating system (ARAS) is important for diagnosis, prediction of prognosis, and management of patients with disorders of impaired consciousness. In the current study, we attempted to reconstruct the direct neural pathway between the brainstem reticular formation (RF) and the cerebral cortex in normal subjects, using diffusion tensor imaging (DTI). Forty-one healthy subjects were recruited for this study. DTIs were performed using a sensitivity-encoding head coil at 1.5Tesla with FMRIB Software Library. For connectivity of the brainstem RF, we used two regions of interest (ROIs) for the brainstem RF (seed ROI) and the thalamus and hypothalamus (exclusion ROI). Connectivity was defined as the incidence of connection between the brainstem RF and target brain regions at the threshold of 5 and 50 streamlines. Regarding the thresholds of 5 and 50, the brainstem RF showed high connectivity to the lateral prefrontal cortex (lPFC, 67.1% and 20.7%) and ventromedial prefrontal cortex (vmPFC, 50.0% and 18.3%), respectively. In contrast, the brainstem RF showed low connectivity to the primary motor cortex (31.7% and 3.7%), premotor cortex (24.4% and 3.7%), primary somatosensory cortex (23.2% and 2.4%), orbitofrontal cortex (17.1% and 7.3%), and posterior parietal cortex (12.2% and 0%), respectively. The brainstem RF was mainly connected to the prefrontal cortex, particularly lPFC and vmPFC. We believe that the methodology and results of this study would be useful to clinicians involved in the care of patients with impaired consciousness and researchers in studies of the ARAS. PMID:26363340

  15. The effects of acute alcohol exposure on the response properties of neurons in visual cortex area 17 of cats

    International Nuclear Information System (INIS)

    Physiological and behavioral studies have demonstrated that a number of visual functions such as visual acuity, contrast sensitivity, and motion perception can be impaired by acute alcohol exposure. The orientation- and direction-selective responses of cells in primary visual cortex are thought to participate in the perception of form and motion. To investigate how orientation selectivity and direction selectivity of neurons are influenced by acute alcohol exposure in vivo, we used the extracellular single-unit recording technique to examine the response properties of neurons in primary visual cortex (A17) of adult cats. We found that alcohol reduces spontaneous activity, visual evoked unit responses, the signal-to-noise ratio, and orientation selectivity of A17 cells. In addition, small but detectable changes in both the preferred orientation/direction and the bandwidth of the orientation tuning curve of strongly orientation-biased A17 cells were observed after acute alcohol administration. Our findings may provide physiological evidence for some alcohol-related deficits in visual function observed in behavioral studies.

  16. 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 ...

  17. 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.

  18. 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. PMID:22313511

  19. 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.

  20. Down-regulation of 3H-imipramine binding sites in rat cerebral cortex prenatal exposure to antidepressants

    International Nuclear Information System (INIS)

    Several antidepressant drugs were given to pregnant rats in the last 15 days of gestation and 3H-imipramine binding (3H-IMI) was subsequently measured in the cerebral cortex of the offspring. The selective serotonin (5-HT) uptake blockers chlorimipramine and fluoxetine as well as the selective monoamine oxidase (MAO) inhibitors clorgyline and deprenyl induced, after prenatal exposure, a down-regulation of 3H-IMI binding sites at postnatal day 25. The density of these binding sites was still reduced at postnatal day 90 in rats exposed in utero to the MAO inhibitors. The antidepressants desipramine and nomifensine were ineffective in this respect. After chronic treatment of adult animals, only chlorimipramine was able to down-regulate the 3H-IMI binding sites. Consequently, prenatal exposure of rats to different antidepressant drugs affecting predominantly the 5-HT systems induces more marked and long-lasting effects on cortical 3H-IMI binding sites. The results suggest that the developing brain is more susceptible to the actions of antidepressants

  1. 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.

  2. Polychlorinated biphenyls, organochlorinated pesticides, and polybrominated diphenyl ethers in the cerebral cortex of wild river otters (Lontra canadensis)

    Energy Technology Data Exchange (ETDEWEB)

    Basu, Niladri [National Wildlife Research Center, Canadian Wildlife Service, Environment Canada, Ottawa, Ontario, K1A 0H3 (Canada)]. E-mail: nbasu@uottawa.ca; Scheuhammer, Anton M. [National Wildlife Research Center, Canadian Wildlife Service, Environment Canada, Ottawa, Ontario, K1A 0H3 (Canada); O' Brien, Mike [Furbearers and Upland Game, Nova Scotia Department of Natural Resources, Kentville, Nova Scotia, B4N 4E5 (Canada)

    2007-09-15

    We measured the levels of ortho-substituted polychlorinated biphenyls (PCB), organochlorinated pesticides (OCP), and polybrominated diphenyl ethers (PBDE) in the cerebral cortex of river otters (Lontra canadensis) trapped from Ontario and Nova Scotia between 2002 and 2004. The mean concentration of total PCBs was 70.9 {+-} 12.1 ng/g l.w., and congeners 153, 180 and 138 accounted for nearly 60% of the sum. The mean concentration of total OCPs was 21.2 {+-} 3.7 ng/g l.w., and hexachlorobenzene (32.6% of total) and DDE (28.1%) accounted for the majority. The mean concentration of total PBDEs was 3.2 {+-} 0.6 ng/g l.w., and congeners 99 (44.9%), 153 (30.5%), and 100 (24.7%) were measured at the indicated percentages. There was no relationship between these residue data and concentrations of brain mercury or neurochemical receptors and enzymes as determined in earlier studies on these same animals. - River otters accumulated PCBs, OCPs, and PBDEs, but at levels below thresholds for neurotoxic effects.

  3. Polychlorinated biphenyls, organochlorinated pesticides, and polybrominated diphenyl ethers in the cerebral cortex of wild river otters (Lontra canadensis)

    International Nuclear Information System (INIS)

    We measured the levels of ortho-substituted polychlorinated biphenyls (PCB), organochlorinated pesticides (OCP), and polybrominated diphenyl ethers (PBDE) in the cerebral cortex of river otters (Lontra canadensis) trapped from Ontario and Nova Scotia between 2002 and 2004. The mean concentration of total PCBs was 70.9 ± 12.1 ng/g l.w., and congeners 153, 180 and 138 accounted for nearly 60% of the sum. The mean concentration of total OCPs was 21.2 ± 3.7 ng/g l.w., and hexachlorobenzene (32.6% of total) and DDE (28.1%) accounted for the majority. The mean concentration of total PBDEs was 3.2 ± 0.6 ng/g l.w., and congeners 99 (44.9%), 153 (30.5%), and 100 (24.7%) were measured at the indicated percentages. There was no relationship between these residue data and concentrations of brain mercury or neurochemical receptors and enzymes as determined in earlier studies on these same animals. - River otters accumulated PCBs, OCPs, and PBDEs, but at levels below thresholds for neurotoxic effects

  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. 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...

  6. 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.

  7. 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...

  8. Characterization of excitatory and inhibitory neuron activation in the mouse medial prefrontal cortex following palatable food ingestion and food driven exploratory behavior

    OpenAIRE

    Gaykema, Ronald P. A.; Nguyen, Xuan-Mai T.; Boehret, Jessica M.; Lambeth, Philip S.; Joy-Gaba, Jonathan; Warthen, Daniel M.; Scott, Michael M

    2014-01-01

    The medial prefrontal cortex (mPFC) is implicated in aspects of executive function, that include the modulation of attentional and memory processes involved in goal selection. Food-seeking behavior has been shown to involve activation of the mPFC, both during the execution of strategies designed to obtain food and during the consumption of food itself. As these behaviors likely require differential engagement of the prefrontal cortex, we hypothesized that the pattern of neuronal activation wo...

  9. 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

  10. 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

  11. 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 of...

  12. Perceptual load affects spatial tuning of neuronal populations in human early visual cortex.

    OpenAIRE

    Haas, B.; Schwarzkopf, D. S.; Anderson, E. J.; Rees, G

    2014-01-01

    Summary Withdrawal of attention from a visual scene as a result of perceptual load modulates overall levels of activity in human visual cortex [1], but its effects on cortical spatial tuning properties are unknown. Here we show attentional load at fixation affects the spatial tuning of population receptive fields (pRFs) in early visual cortex (V1–3) using functional magnetic resonance imaging (fMRI). We found that, compared to low perceptual load, high perceptual load yielded a ‘blurrier’ rep...

  13. Estrogen formation and binding in the cerebral cortex of the developing rhesus monkey

    International Nuclear Information System (INIS)

    These studies were undertaken to determine whether estrogen receptors and the microsomal enzyme system called the aromatase complex, which is responsible for conversion of androgen to estrogen, are present in the brain of the rhesus monkey during perinatal life. Four monkeys (three females-one fetus removed on day 153 of gestation and two infants, 5 and 6 days postnatal-and 1 male, 2 days postnatal) were studied. Cytosol estrogen receptors were detected in all brain regions examined. The apparent equilibrium dissociations constants for reaction of these sites with 3H-moxestrol were similar to those for uterine and pituitary cytosol estrogen receptors (0.3-1.1 nM). Within the brain, highest levels of binding were observed in the hypothalamus-preoptic area, with fairly even, lower concentrations throughout the cortical structures. Aromatase complex activity was detected in the majority of the tissue specimens. The highest levels of estrogen formation were observed in the hypothalamus. Among the cortical samples, the highest levels of aromatase complex activity were found in regions of the association cortex. The lowest levels of aromatase activity were found in the somatosensory and motor cortices of the postnatal animals. These results suggest that locally-formed estrogen may be involved in the effects of circulating androgens on the developing primate neocortex

  14. Altered intrinsic properties and bursting activities of neurons in layer IV of somatosensory cortex from Fmr-1 knockout mice.

    Science.gov (United States)

    Zhang, Linming; Liang, Zhanrong; Zhu, Pingping; Li, Meng; Yi, Yong-Hong; Liao, Wei-Ping; Su, Tao

    2016-06-01

    Neuroadaptations and alterations in neuronal excitability are critical in brain maturation and many neurological diseases. Fragile X syndrome (FXS) is a pervasive neurodevelopmental disorder characterized by extensive synaptic and circuit dysfunction. It is still unclear about the alterations in intrinsic excitability of individual neurons and their link to hyperexcitable circuitry. In this study, whole cell patch-clamp recordings were employed to characterize the membrane and firing properties of layer IV cells in slices of the somatosensory cortex of Fmr-1 knockout (KO) mice. These cells generally exhibited a regular spiking (RS) pattern, while there were significant increases in the number of cells that adopted intrinsic bursting (IB) compared with age-matched wild type (WT) cells. The cells subgrouped according to their firing patterns and maturation differed significantly in membrane and discharge properties between KO and WT. The changes in the intrinsic properties were consistent with highly facilitated discharges in KO cells induced by current injection. Spontaneous activities of RS neurons driven by local network were also increased in the KO cells, especially in neonate groups. Under an epileptiform condition mimicked by omission of Mg(2+) in extracellular solution, these RS neurons from KO mice were more likely to switch to burst discharges. Analysis on bursts revealed that the KO cells tended to form burst discharges and even severe events manifested as seizure-like ictal discharges. These results suggest that alterations in intrinsic properties in individual neurons are involved in the abnormal excitability of cortical circuitry and possibly account for the pathogenesis of epilepsy in FXS. PMID:27048919

  15. Distinct ensembles of medial prefrontal cortex neurons are activated by threatening stimuli that elicit excitation vs. inhibition of movement.

    Science.gov (United States)

    Halladay, Lindsay R; Blair, Hugh T

    2015-08-01

    Neural circuits controlling defensive behavior were investigated by recording single units in medial prefrontal cortex (mPFC) and dorsolateral periaqueductal gray (dlPAG) while rats expressed conditioned fear responses to an auditory conditioned stimulus (CS; 20-s train of white noise pips) previously paired with an aversive unconditioned stimulus (US; 2-s train of periorbital shocks). The CS elicited conditioned movement inhibition (CMI; characterized by decreased movement speed and freezing) when rats had not recently encountered the US, whereas the CS elicited conditioned movement excitation (CME; characterized by increased movement speed and flight behavior) after recent US encounters. Many mPFC neurons were "strategy-selective" cells that changed their firing rates only when the CS elicited CME (15/71) or CMI (13/71) responses, whereas few mPFC cells (4/71) responded nonselectively to the CS during either response. By contrast, many dlPAG neurons (20/74) responded nonselectively to the CS, but most (40/74) were excited by the CS selectively during CME trials (and none during CMI trials). CME-selective neurons in dlPAG responded phasically after CS pips that elicited CME responses, whereas CME-selective neurons in mPFC showed tonically elevated activity before and after pips that evoked CME responses. These findings suggest that, at the time when the CS occurs, tonic firing rates of CME- and CMI-selective mPFC neurons may bias the rat's choice of whether to express CME vs. CMI responses, perhaps via projections to downstream structures (such as amygdala and PAG) that influence how sensory stimuli are mapped onto motor circuits that drive the expression of competing behaviors. PMID:25972588

  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. 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

  18. Selective activation of dorsal raphe nucleus-projecting neurons in the ventral medial prefrontal cortex by controllable stress.

    Science.gov (United States)

    Baratta, Michael V; Zarza, Christina M; Gomez, Devan M; Campeau, Serge; Watkins, Linda R; Maier, Steven F

    2009-09-01

    Exposure to uncontrollable stressors produces a variety of behavioral consequences (e.g. exaggerated fear, reduced social exploration) that do not occur if the stressor is controllable. In addition, an initial experience with a controllable stressor can block the behavioral and neural responses to a later uncontrollable stressor. The serotonergic (5-HT) dorsal raphe nucleus (DRN) has come to be viewed as a critical structure in mediating the behavioral effects of uncontrollable stress. Recent work suggests that the buffering effects of behavioral control on the DRN-dependent behavioral outcomes of uncontrollable stress require ventral medial prefrontal cortex (mPFCv) activation at the time of behavioral control. The present studies were conducted to directly determine whether or not controllable stress selectively activates DRN-projecting neurons within the mPFCv. To examine this possibility in the rat, we combined retrograde tracing (fluorogold iontophoresed into the DRN) with Fos immunohistochemistry, a marker for neural activation. Exposure to controllable, relative to uncontrollable, stress increased Fos expression in fluorogold-labeled neurons in the prelimbic region (PL) of the mPFCv. Furthermore, in a separate experiment, a prior experience with controllable stress led to potentiation of Fos expression in retrogradely labeled PL neurons in response to an uncontrollable stressor 1 week later. These results suggest that the PL selectively responds to behavioral control and utilizes such information to regulate the brainstem response to ongoing and subsequent stressors. PMID:19686468

  19. The response properties of neurons in different fields of the auditory cortex in the rat

    Czech Academy of Sciences Publication Activity Database

    Profant, Oliver; Burianová, Jana; Syka, Josef

    2013-01-01

    Roč. 296, February (2013), s. 51-59. ISSN 0378-5955 R&D Projects: GA ČR(CZ) GAP303/12/1347; GA ČR(CZ) GBP304/12/G069 Institutional support: RVO:68378041 Keywords : auditory cortex * fequency representation * axon terminals Subject RIV: FH - Neurology Impact factor: 2.848, year: 2013

  20. Cooling of the auditory cortex modifies neuronal activity in the inferior colliculus in rats

    Czech Academy of Sciences Publication Activity Database

    Popelář, Jiří; Šuta, Daniel; Lindovský, Jiří; Bureš, Zbyněk; Pysaněnko, Kateryna; Chumak, Tetyana; Syka, Josef

    2016-01-01

    Roč. 332, feb (2016), s. 7-16. ISSN 0378-5955 R&D Projects: GA ČR(CZ) GBP304/12/G069; GA ČR(CZ) GAP303/12/1347 Institutional support: RVO:68378041 Keywords : auditory cortex * cooling * cortical inactivation * efferent system Subject RIV: ED - Physiology Impact factor: 2.968, year: 2014

  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. 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...

  4. Ischemic Postconditioning Alleviates Neuronal Injury Caused by Relief of Carotid Stenosis in a Rat Model of Cerebral Hypoperfusion

    Directory of Open Access Journals (Sweden)

    Pengfei Ge

    2012-10-01

    Full Text Available The effects of early relief of heavy bilateral carotid stenosis and ischemic postconditioning on hippocampus CA1 neurons are still unclear. In this study, we used a rat model to imitate severe bilateral carotid stenosis in humans. The rats were divided into sham group, carotid stenosis group, stenosis relief group and ischemic postconditioning group. Ischemic postconditioning consisted of three cycles of 30 s ischemia and 30 s reperfusion. The cerebral blood flow was measured with a laser Doppler flowmeter. Neuronal death in the CA1 region was observed by hematoxylin-eosin staining, and the number of live neurons was assessed by cell counting under a light microscope. The levels of oxidative products MDA and 8-iso-PGF2α, inflammatory factors IL-1β and TNF-α, and the activities of anti-oxidative enzymes SOD and CAT were assayed by specific enzyme-linked immunosorbent assay (ELISA kits, respectively. We found that relief of carotid stenosis and ischemic postconditioning could increase cerebral blood flow. When stenosis was relieved, the percentage of live neurons was 66.6% ± 6.2% on day 3 and 62.3% ± 9.8% on day 27, which was significantly higher than 55.5% ± 4.8% in stenosis group. Ischemic postconditioning markedly improved the live neurons to 92.5% ± 6.7% on day 3 and 88.6% ± 9.1% on day 27. Further study showed that, neuronal death caused by relief of stenosis is associated with increased oxidative stress and enhanced inflammatory response, and the protection of ischemic postconditioning is related to inhibition of oxidative stress and suppression of inflammatory response.

  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. 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.

  7. Effect of repeated ('binge') dosing of MDMA to rats housed at normal and high temperature on neurotoxic damage to cerebral 5-HT and dopamine neurones.

    Science.gov (United States)

    Sanchez, Veronica; O'shea, Esther; Saadat, Kathryn S; Elliott, J Martin; Colado, M Isabel; Green, A Richard

    2004-09-01

    The technique of 'binge' dosing (several doses in one session) by recreational users of 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) requires evaluation in terms of its consequences on the acute hyperthermic response and long-term neurotoxicity. We examined the neurotoxic effects of this dosing schedule on 5-HT and dopamine neurones in the rat brain. When repeated (three) doses of MDMA (2, 4 and 6 mg/kg i.p.) were given 3 h apart to rats housed at 19 degrees C, a dose-dependent acute hyperthermia and long-term loss of 5-HT was observed in several brain regions (hippocampus, cortex and striatum), with an approximate 50% loss following 3 x 4 mg/kg and 65% decrease following 3 x 6 mg/kg. No decrease in striatal dopamine content was detected. When MDMA (4 mg/kg i.p.) was given repeatedly to rats housed at 30 degrees C, a larger acute hyperthermic response than that observed in rats treated at 19 degrees C environment was seen (maximum response 2.6 +/- 0.1 degrees C versus 1.3 +/- 0.2 degrees C). A long-term cerebral 5-HT loss of approximately 65% was also detected in both the cortex and hippocampus, but no loss in striatal dopamine content occurred. These data emphasize the increased acute hyperthermic response and neurotoxicity which occurs when MDMA is administered in a hot room environment compared to normal room temperature conditions, and support the view that MDMA is a selective 5-HT neurotoxin, even when a binge dosing schedule is employed and the rats are present in a hot environment. PMID:15358986

  8. 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.

  9. 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.

  10. 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.

  11. Effects of basic fibroblast growth factor on hippocampal and parietal cortical neuronal cAMP-response element-binding protein expression in a rat model of focal cerebral ischemia/reperfusion

    Institute of Scientific and Technical Information of China (English)

    Chunyu Qu; Xuesong Xing; Jin Zang

    2009-01-01

    BACKGROUND: cAMP-response element binding protein (CREB) is a key modulator of various signaling pathways. CREB activation initiates a series of intracellular signaling pathways that promote neuronal survival. OBJECTIVE: To investigate the regulatory effects of basic fibroblast growth factor (bFGF) on cerebral neuronal CREB expression following ischemia/reperfusion injury. DESIGN, TIME AND SETTING: An immunohistochemical detection experiment was performed at the Department of Anatomy, Shenyang Medical College, between October 2006 and April 2008.MATERIALS: A total of 60 healthy, adult, Wistar rats were randomly divided into three groups: sham-operated (n=12), ischemia/reperfusion (n=24), and bFGF-treated (n=24). Rabbit anti-rat CREB (1: 100) and biotin labeled goat anti-rabbit IgG were purchased from the Wuhan Boster Company, China. MetaMorph-evolution MPS. 0-BX51 microscopy imaging system was provided by China Medical University, China. METHODS: Rat models of cerebral ischemia/reperfusion injury were developed using the suture method for right middle cerebral artery occlusion. Two-hour ischemia was followed by reperfusion. Rats from the bFGF-treated and ischemia/reperfusion groups were intraperitoneally administered endogenous bFGF (500 IU/mL, 2 000 IU/kg) or an equal amount of physiological saline. Rats from the sham-operated group underwent a similar surgical procedure, without induction of ischemia/reperfusion injury and drug administration. MAIN OUTCOME MEASURES: After 48-hour reperfusion, hippocampal and parietal cortical neuronal CREB expression was detected by immunohistochemistry, and the absorbance of hippocampal CREB-positive products was determined using MetaMorph-evolutionMP5.0-BX51 microscopy imaging system. RESULTS: The sham-operated group exhibited noticeable CREB expression in hippocampal and parietal cortical neurons. In the ischemia/reperfusion group, the CREB expression was discrete and neurons were poorly arranged. The bFGF-treated group

  12. Differential binding of /sup 3/H-imipramine and /sup 3/H-mianserin in rat cerebral cortex

    Energy Technology Data Exchange (ETDEWEB)

    Dumbrille-Ross, A.; Tang, S.W.; Coscina, D.V.

    1981-11-16

    Drug competition profiles, effect of raphe lesion, and sodium dependency of the binding of two antidepressant drugs /sup 3/H-imipramine and /sup 3/H-mianserin to rat cerebral cortex homogenate were compared to examine whether the drugs bound to a common ''antidepressant receptor.'' Of the neurotransmitters tested, only serotonin displaced binding of both /sup 3/H-imipramine and /sup 3/H-mianserin. /sup 3/H-Mianserin binding was potently displaced by serotonin S/sub 2/ antagonists and exhibited a profile similar to that of /sup 3/H-spiperone binding. In the presence of the serotonin S/sub 2/ antagonist spiperone, antihistamines (H/sub 1/) potently displaced /sup 3/H-mianserin binding. /sup 3/H-Imipramine binding was displaced potently by serotonin uptake inhibitors. The order of potency of serotonergic drugs in displacing /sup 3/H-imipramine binding was not similar to their order in displacing /sup 3/H-spiperone or -3H-serotonin binding. Prior midbrain raphe lesions greatly decreased the binding of /sup 3/H-imipramine but did not alter binding of /sup 3/H-mianserin. Binding of /sup 3/H-imipramine but not /sup 3/H-mianserin was sodium dependent. These results show that /sup 3/H-imipramine and /sup 3/H-mianserin bind to different receptors. /sup 3/H-Imipramine binds to a presynaptic serotonin receptor which is probably related to a serotonin uptake recognition site, the binding of which is sodium dependent. /sup 3/H-Mianserin binds to postsynaptic receptors, possibly both serotonin S/sub 2/ and histamine H/sub 1/ receptors, the binding of which is sodium independent.

  13. 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

  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%; mo