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Sample records for rat brain coupled

  1. Neurons from rat brain coupled to transistors

    NASA Astrophysics Data System (ADS)

    Vassanelli, S.; Fromherz, P.

    Field-effect transistors form spontaneously capacitive junctions with cultured nerve cells from rat brains. The transfer of ac signals from neurons to silicon is studied and used to parametrize an equivalent circuit. The coupling is distinctly weaker than in junctions assembled with leech nerve cells. The implications with respect to the recording and stimulation of neuronal activity by silicon devices are considered.

  2. Regional differences in neurovascular coupling in rat brain as determined by fMRI and electrophysiology.

    PubMed

    Sloan, H L; Austin, V C; Blamire, A M; Schnupp, J W H; Lowe, A S; Allers, K A; Matthews, P M; Sibson, N R

    2010-11-01

    Increases in neuronal activity induce local increases in cerebral perfusion. However, our understanding of the processes underlying this neurovascular coupling remains incomplete and, particularly, how these vary across the brain. Recent work supports an important role for astrocytes in neurovascular coupling, in large part via activation of their metabotropic glutamate receptors (mGluR). Here, using a combination of functional magnetic resonance imaging (fMRI) and electrophysiology we demonstrate regional heterogeneity in the mechanisms underlying neurovascular coupling. Direct electrical stimulation of the rat hindpaw sensorimotor cortex induces blood oxygenation level dependent (BOLD) and cerebral blood volume (CBV) fMRI responses in several anatomically distinct cortical and subcortical structures. Following intraperitoneal administration of the type 5 mGluR antagonist, MPEP, both BOLD and CBV responses to cortical stimulation were significantly reduced, whilst the local field potential (LFP) responses remained largely constant. Spatially, the degree of reduction in fMRI responses varied between cortical and subcortical regions (primary cortex approximately 18% vs. striatum approximately 66%), and also between primary and secondary cortical areas ( approximately 18% vs. approximately 55%). Similarly, greater decreases in response amplitude were seen in the contralateral secondary cortex ( approximately 91%) and ipsilateral striatum (approximately 70%), compared to the primary cortex (approximately 44%). Following MPEP, a negative component of the BOLD and CBV responses became more apparent, suggesting that different mechanisms mediate vasodilatory and vasoconstrictory responses. Interestingly, under baseline conditions the quantitative relationship between fMRI and LFP responses in cortical and subcortical regions was markedly different. Our data indicate that coupling between neuronal and fMRI responses is neither empirically nor mechanistically consistent

  3. Biofuel cell based on microscale nanostructured electrodes with inductive coupling to rat brain neurons.

    PubMed

    Andoralov, Viktor; Falk, Magnus; Suyatin, Dmitry B; Granmo, Marcus; Sotres, Javier; Ludwig, Roland; Popov, Vladimir O; Schouenborg, Jens; Blum, Zoltan; Shleev, Sergey

    2013-01-01

    Miniature, self-contained biodevices powered by biofuel cells may enable a new generation of implantable, wireless, minimally invasive neural interfaces for neurophysiological in vivo studies and for clinical applications. Here we report on the fabrication of a direct electron transfer based glucose/oxygen enzymatic fuel cell (EFC) from genuinely three-dimensional (3D) nanostructured microscale gold electrodes, modified with suitable biocatalysts. We show that the process underlying the simple fabrication method of 3D nanostructured electrodes is based on an electrochemically driven transformation of physically deposited gold nanoparticles. We experimentally demonstrate that mediator-, cofactor-, and membrane-less EFCs do operate in cerebrospinal fluid and in the brain of a rat, producing amounts of electrical power sufficient to drive a self-contained biodevice, viz. 7 μW cm(-2) in vitro and 2 μW cm(-2) in vivo at an operating voltage of 0.4 V. Last but not least, we also demonstrate an inductive coupling between 3D nanobioelectrodes and living neurons. PMID:24253492

  4. Biofuel Cell Based on Microscale Nanostructured Electrodes with Inductive Coupling to Rat Brain Neurons

    NASA Astrophysics Data System (ADS)

    Andoralov, Viktor; Falk, Magnus; Suyatin, Dmitry B.; Granmo, Marcus; Sotres, Javier; Ludwig, Roland; Popov, Vladimir O.; Schouenborg, Jens; Blum, Zoltan; Shleev, Sergey

    2013-11-01

    Miniature, self-contained biodevices powered by biofuel cells may enable a new generation of implantable, wireless, minimally invasive neural interfaces for neurophysiological in vivo studies and for clinical applications. Here we report on the fabrication of a direct electron transfer based glucose/oxygen enzymatic fuel cell (EFC) from genuinely three-dimensional (3D) nanostructured microscale gold electrodes, modified with suitable biocatalysts. We show that the process underlying the simple fabrication method of 3D nanostructured electrodes is based on an electrochemically driven transformation of physically deposited gold nanoparticles. We experimentally demonstrate that mediator-, cofactor-, and membrane-less EFCs do operate in cerebrospinal fluid and in the brain of a rat, producing amounts of electrical power sufficient to drive a self-contained biodevice, viz. 7 μW cm-2 in vitro and 2 μW cm-2 in vivo at an operating voltage of 0.4 V. Last but not least, we also demonstrate an inductive coupling between 3D nanobioelectrodes and living neurons.

  5. Biofuel Cell Based on Microscale Nanostructured Electrodes with Inductive Coupling to Rat Brain Neurons

    PubMed Central

    Andoralov, Viktor; Falk, Magnus; Suyatin, Dmitry B.; Granmo, Marcus; Sotres, Javier; Ludwig, Roland; Popov, Vladimir O.; Schouenborg, Jens; Blum, Zoltan; Shleev, Sergey

    2013-01-01

    Miniature, self-contained biodevices powered by biofuel cells may enable a new generation of implantable, wireless, minimally invasive neural interfaces for neurophysiological in vivo studies and for clinical applications. Here we report on the fabrication of a direct electron transfer based glucose/oxygen enzymatic fuel cell (EFC) from genuinely three-dimensional (3D) nanostructured microscale gold electrodes, modified with suitable biocatalysts. We show that the process underlying the simple fabrication method of 3D nanostructured electrodes is based on an electrochemically driven transformation of physically deposited gold nanoparticles. We experimentally demonstrate that mediator-, cofactor-, and membrane-less EFCs do operate in cerebrospinal fluid and in the brain of a rat, producing amounts of electrical power sufficient to drive a self-contained biodevice, viz. 7 μW cm−2 in vitro and 2 μW cm−2 in vivo at an operating voltage of 0.4 V. Last but not least, we also demonstrate an inductive coupling between 3D nanobioelectrodes and living neurons. PMID:24253492

  6. Angiotensin II receptor subtypes are coupled with distinct signal-transduction mechanisms in neurons and astrocytes from rat brain

    SciTech Connect

    Sumners, C.; Wei Tang; Zelezna, B.; Raizada, M.K. )

    1991-09-01

    Both neurons and astrocytes contain specific receptors for angiotensin II (AII). The authors used selective ligands for the AT{sub 1} and AT{sub 2} types of AII receptors to investigate the expression of functional receptor subtypes in astrocyte cultures and neuron cultures from 1-day-old (neonatal) rat brain. In astrocyte cultures, competition of {sup 125}I-labeled AII ({sup 125}I-AII) specific binding with AT{sub 1} (DuP753) or AT{sub 2} {l brace}PD123177, CGP42112A, (Phe(p-NH{sub 2}){sup 6})AII{r brace} selective receptor ligands revealed a potency series of AII > DuP753 > > > CGP42112A > (Phe(p-NH{sub 2}){sup 6})AII > PD123177. These results suggest a predominance of the AT{sub 1} receptor subtype in neonatal astrocytes. {sup 125}I-AII specific binding to neonate neuronal cultures was reduced 73-84% by 1 {mu} MPD123177, and the residual {sup 125}I-AII specific binding was eliminated by DuP753. The results suggest that astrocyte cultures from neonatal rat brains contain predominantly AT{sub 1} receptors that are coupled to a stimulation of inositophospholipid hydrolysis. In contrast, neuron cultures from neonatal rat brain contain mostly AT{sub 2} receptors that are coupled to a reduction in basal cGMP levels, but a smaller population of AT{sub 1} receptors is also present in these neurons.

  7. Quantitative analysis of olanzapine in rat brain microdialysates by HPLC-MS/MS coupled with column-switching technique.

    PubMed

    Zheng, Qiaoling; Wang, Feng; Li, Huande; Xu, Ping; Tang, Huaibo; Li, Lanfang; Cheng, Rihua

    2012-09-15

    A rapid and sensitive liquid chromatography-tandem mass spectrometric (LC-MS/MS) method coupled with column-switching technique was developed for the determination of olanzapine in rat brain microdialysates. A C8 guard column was used to desalt the samples before analytical separation on a C18 column and detection with tandem mass spectrometry. The mobile phase consisted of methanol/acetonitrile/water (v/v/v, 22.5/22.2/55) was used for desalting and the mobile phase consisted of methanol/acetonitrile/water (v/v/v, 43/43/14) was for analytical separation, water in both mobile phases contained 0.1% ammonium acetate. The lower limit of quantification (LLOQ) for olanzapine was 0.085 ng/ml. The method was linear from LLOQ to 34 ng/ml with a coefficient of determination >0.998. Intra- and inter-day accuracy and precision were determined with variability less than 13.24% (R.S.D). This sensitive method was successfully applied to quantify the concentration of olanzapine in rat brain microdialysates. With this study, the effect of the alcohol extract of Schisandra sphenanthera Rehd. et Wils on the concentration of olanzapine in brain was investigated. PMID:22917592

  8. Distribution of temperature changes and neurovascular coupling in rat brain following 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") exposure.

    PubMed

    Coman, Daniel; Sanganahalli, Basavaraju G; Jiang, Lihong; Hyder, Fahmeed; Behar, Kevin L

    2015-10-01

    (+/-)3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") is an abused psychostimulant that produces strong monoaminergic stimulation and whole-body hyperthermia. MDMA-induced thermogenesis involves activation of uncoupling proteins (UCPs), primarily a type specific to skeletal muscle (UCP-3) and absent from the brain, although other UCP types are expressed in the brain (e.g. thalamus) and might contribute to thermogenesis. Since neuroimaging of brain temperature could provide insights into MDMA action, we measured spatial distributions of systemically administered MDMA-induced temperature changes and dynamics in rat cortex and subcortex using a novel magnetic resonance method, Biosensor Imaging of Redundant Deviation in Shifts (BIRDS), with an exogenous temperature-sensitive probe (thulium ion and macrocyclic chelate 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetramethyl-1,4,7,10-tetraacetate (DOTMA(4-))). The MDMA-induced temperature rise was greater in the cortex than in the subcortex (1.6 ± 0.4 °C versus 1.3 ± 0.4 °C) and occurred more rapidly (2.0 ± 0.2 °C/h versus 1.5 ± 0.2 °C/h). MDMA-induced temperature changes and dynamics in the cortex and body were correlated, although the body temperature exceeded the cortex temperature before and after MDMA. Temperature, neuronal activity, and blood flow (CBF) were measured simultaneously in the cortex and subcortex (i.e. thalamus) to investigate possible differences of MDMA-induced warming across brain regions. MDMA-induced warming correlated with increases in neuronal activity and blood flow in the cortex, suggesting that the normal neurovascular response to increased neural activity was maintained. In contrast to the cortex, a biphasic relationship was seen in the subcortex (i.e. thalamus), with a decline in CBF as temperature and neural activity rose, transitioning to a rise in CBF for temperature above 37 °C, suggesting that MDMA affected CBF and neurovascular coupling differently in subcortical regions

  9. Implanted, inductively-coupled, radiofrequency coils fabricated on flexible polymeric material: Application to in vivo rat brain MRI at 7 T

    NASA Astrophysics Data System (ADS)

    Ginefri, J.-C.; Rubin, A.; Tatoulian, M.; Woytasik, M.; Boumezbeur, F.; Djemaï, B.; Poirier-Quinot, M.; Lethimonnier, F.; Darrasse, L.; Dufour-Gergam, E.

    2012-11-01

    Combined with high-field MRI scanners, small implanted coils allow for high resolution imaging with locally improved SNR, as compared to external coils. Small flexible implantable coils dedicated to in vivo MRI of the rat brain at 7 T were developed. Based on the Multi-turn Transmission Line Resonator design, they were fabricated with a Teflon substrate using copper micromolding process and a specific metal-polymer adhesion treatment. The implanted coils were made biocompatible by PolyDimethylSiloxane (PDMS) encapsulation. The use of low loss tangent material achieves low dielectric losses within the substrate and the use of the PDMS layer reduces the parasitic coupling with the surrounding media. An implanted coil was implemented in a 7 T MRI system using inductive coupling and a dedicated external pick-up coil for signal transmission. In vivo images of the rat brain acquired with in plane resolution of (150 μm)2 thanks to the implanted coil revealed high SNR near the coil, allowing for the visualization of fine cerebral structures.

  10. Novel G protein-coupled oestrogen receptor GPR30 shows changes in mRNA expression in the rat brain over the oestrous cycle.

    PubMed

    Spary, Emma J; Chapman, Sally E; Sinfield, John K; Maqbool, Azhar; Kaye, Jean; Batten, Trevor F C

    2013-01-01

    Oestrogen influences autonomic function via actions at classical nuclear oestrogen receptors α and β in the brain, and recent evidence suggests the orphan G protein-coupled receptor GPR30 may also function as a cytoplasmic oestrogen receptor. We investigated the expression of GPR30 in female rat brains throughout the oestrous cycle and after ovariectomy to determine whether GPR30 expression in central autonomic nuclei is correlated with circulating oestrogen levels. In the nucleus of the solitary tract (NTS), ventrolateral medulla (VLM) and periaqueductal gray (PAG) GPR30 mRNA, quantified by real-time PCR, was increased in proestrus and oestrus. In ovariectomised (OVX) rats, expression in NTS and VLM appeared increased compared to metoestrus, but in the hypothalamic paraventricular nucleus and PAG lower mRNA levels were seen in OVX. GPR30-like immunoreactivity (GPR30-LI) colocalised with Golgi in neurones in many brain areas associated with autonomic pathways, and analysis of numbers of immunoreactive neurones showed differences consistent with the PCR data. GPR30-LI was found in a variety of transmitter phenotypes, including cholinergic, serotonergic, catecholaminergic and nitrergic neurones in different neuronal groups. These observations support the view that GPR30 could act as a rapid transducer responding to oestrogen levels and thus modulate the activity of central autonomic pathways. PMID:22378360

  11. Gene expression in rat brain.

    PubMed

    Milner, R J; Sutcliffe, J G

    1983-08-25

    191 randomly selected cDNA clones prepared from rat brain cytoplasmic poly (A)+ RNA were screened by Northern blot hybridization to rat brain, liver and kidney RNA to determine the tissue distribution, abundance and size of the corresponding brain mRNA. 18% hybridized to mRNAs each present equally in the three tissues, 26% to mRNAs differentially expressed in the tissues, and 30% to mRNAs present only in the brain. An additional 26% of the clones failed to detect mRNA in the three tissues at an abundance level of about 0.01%, but did contain rat cDNA as demonstrated by Southern blotting; this class probably represents rare mRNAs expressed in only some brain cells. Therefore, most mRNA expressed in brain is either specific to brain or otherwise displays regulation. Rarer mRNA species tend to be larger than the more abundant species, and tend to be brain specific; the rarest, specific mRNAs average 5000 nucleotides in length. Ten percent of the clones hybridize to multiple mRNAs, some of which are expressed from small multigenic families. From these data we estimate that there are probably at most 30,000 distinct mRNA species expressed in the rat brain, the majority of which are uniquely expressed in the brain. PMID:6193485

  12. Activation of G protein-coupled estrogen receptor 1 (GPER-1) ameliorates blood-brain barrier permeability after global cerebral ischemia in ovariectomized rats.

    PubMed

    Lu, Dan; Qu, Yan; Shi, Fei; Feng, Dayun; Tao, Kai; Gao, Guodong; He, Shiming; Zhao, Tianzhi

    2016-08-19

    G protein-coupled estrogen receptor 1 (GPER-1) plays important roles in estrogen-mediated neuroprotection. However, protective effects of GPER-1 on blood-brain barrier (BBB) after ischemic stroke have not been determined. The aim of present study was to determine whether GPER-1 activation ameliorates BBB permeability in ovariectomized rats with induced global cerebral ischemia (GCI). GCI was induced by 4-vessel occlusion for 20 min followed by 24 h reperfusion period. The GPER-1 agonist (G1) was bilaterally administered immediately upon reperfusion by intracerebroventricular (icv) injection. We found that the GPER-1 agonist could significantly decrease immunoglobulin G (IgG) extravasation and increase the levels of tight junctions (occludin and claudin-5) in the CA1 at 24 h of reperfusion after GCI. Further, protein levels of vascular endothelial growth factor A (VEGF-A) was significantly decreased in the ischemic CA1 by G1. Our results suggest that GPER-1 activation reduce tight junctions disruption via inhibition of VEGF-A expression after ischemic injury. PMID:27311857

  13. A high-throughput microdialysis-parallel solid phase extraction-inductively coupled plasma mass spectrometry hyphenated system for continuous monitoring of extracellular metal ions in living rat brain.

    PubMed

    Su, Cheng-Kuan; Hsia, Sheng-Chieh; Sun, Yuh-Chang

    2014-01-24

    To significantly improve the temporal resolving power of in vivo trace brain metal monitoring system, in this paper we describe a novel analytical configuration combining the dual functions of online segmentation of the rat brain microdialysate and parallel solid phase extraction (SPE) of multiple segmented samples. In contrast to traditional SPE procedures, in this study the three pumped media-the buffered rat brain microdialysate, the eluent, and the air stream-were converted to a series of segmented streams through the manipulation of a flow-through stream selector. After optimizing this online automatic MD/parallel poly(vinyl chloride) SPE/inductively coupled plasma mass spectrometry hyphenated system for the analysis of ultra-trace metal ions, the sample volume of the microdialysate was set at 0.83μL, the analytical sequence was repeatable every 20s, and the detection limits were in the range 0.03-0.24μgL(-1), with spike analyses of Mn, Co, Ni, Cu, and Zn in a rat brain ECF sample agreeing well with expected values (88-107%). To further examine the system's practicability, we also performed (i) in vivo dynamic monitoring of these trace metal ions in living rat brain extracellular fluid post-probe implantation (the basal values for Mn, Co, Ni, Cu, and Zn were 1.17±0.18, 1.27±0.36, 2.46±0.62, 0.86±0.37, and 2.35±0.55μgL(-1), respectively) and (ii) real-time visualization of the physiological response to acute neural depolarization elicited upon perfusing a high-K(+) medium through the MD probe. PMID:24388243

  14. The rat brain hippocampus proteome.

    PubMed

    Fountoulakis, Michael; Tsangaris, George T; Maris, Antony; Lubec, Gert

    2005-05-01

    The hippocampus is crucial in memory storage and retrieval and plays an important role in stress response. In humans, the CA1 area of hippocampus is one of the first brain areas to display pathology in Alzheimer's disease. A comprehensive analysis of the hippocampus proteome has not been accomplished yet. We applied proteomics technologies to construct a two-dimensional database for rat brain hippocampus proteins. Hippocampus samples from eight months old animals were analyzed by two-dimensional electrophoresis and the proteins were identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. The database comprises 148 different gene products, which are in the majority enzymes, structural proteins and heat shock proteins. It also includes 39 neuron specific gene products. The database may be useful in animal model studies of neurological disorders. PMID:15797529

  15. A rapid and simple method for the simultaneous determination of four endogenous monoamine neurotransmitters in rat brain using hydrophilic interaction liquid chromatography coupled with atmospheric-pressure chemical ionization tandem mass spectrometry.

    PubMed

    Zhou, Wenbin; Zhu, Bangjie; Liu, Feng; Lyu, Chunming; Zhang, Shen; Yan, Chao; Cheng, Yu; Wei, Hai

    2015-10-01

    Endogenous monoamine neurotransmitters play an essential role in neural communication in mammalians. Many quantitative methods for endogenous monoamines have been developed during recent decades. Yet, matrix effect was usually a challenge in the quantification, in many cases asking for tedious sample preparation or sacrificing sensitivity. In this work, a simple, fast and sensitive method with no matrix effect was developed to simultaneously determine four endogenous monoamines including serotonin, dopamine, epinephrine and norepinephrine in rat brain tissues, using hydrophilic interaction liquid chromatography coupled with atmospheric-pressure chemical ionization tandem mass spectrometry. Various conditions, including columns, chromatographic conditions, ion source, MS/MS conditions, and brain tissue preparation methods, were optimized and validated. Pre-weighed 20mg brain sample could be effectively and reproducibly homogenized and protein-precipitated by 20 times value of 0.2% formic acid in cold organic solvents (methanol-acetonitrile, 10:90, v/v). This method exhibited excellent linearity for all analytes (regression coefficients>0.998 or 0.999). The precision, expressed as coefficients of variation, was less than 3.43% for intra-day analyses and ranged from 4.17% to 15.5% for inter-day analyses. Good performance was showed in limit of detection (between 0.3nM and 3.0nM for all analytes), recovery (90.8-120%), matrix effect (84.4-107%), accuracy (89.8-100%) and stability (88.3-104%). The validated method was well applied to simultaneously determine the endogenous serotonin, dopamine, epinephrine and norepinephrine in four brain sections of 18 Wistar rats. The quantification of four endogenous monoamines in rat brain performed excellently in the sensitivity, high throughput, simple sample preparation and matrix effect. PMID:26363373

  16. Brain α2-adrenoceptors in monoamine-depleted rats: increased receptor density, G coupling proteins, receptor turnover and receptor mRNA

    PubMed Central

    Ribas, Catalina; Miralles, Antonio; Busquets, Xavier; García-Sevilla, Jesús A

    2001-01-01

    This study was designed to assess the molecular and cellular events involved in the up-regulation (and receptor supersensitivity) of brain α2-adrenoceptors as a result of chronic depletion of noradrenaline (and other monoamines) by reserpine. Chronic reserpine (0.25 mg kg−1 s.c., every 48 h for 6 – 14 days) increased significantly the density (Bmax values) of cortical α2-adrenoceptor agonist sites (34 – 48% for [3H]-UK14304, 22 – 32% for [3H]-clonidine) but not that of antagonist sites (11 – 18% for [3H]-RX821002). Competition of [3H]-RX821002 binding by (−)-adrenaline further indicated that chronic reserpine was associated with up-regulation of the high-affinity state of α2-adrenoceptors. In cortical membranes of reserpine-treated rats (0.25 mg kg−1 s.c., every 48 h for 20 days), the immunoreactivities of various G proteins (Gαi1/2, Gαi3, Gαo and Gαs) were increased (25 – 34%). Because the high-affinity conformation of the α2-adrenoceptor is most probably related to the complex with Gαi2 proteins, these results suggested an increase in signal transduction through α2-adrenoceptors (and other monoamine receptors) induced by chronic reserpine. After α2-adrenoceptor alkylation, the analysis of receptor recovery (Bmax for [3H]-UK14304) indicated that the increased density of cortical α2-adrenoceptors in reserpine-treated rats was probably due to a higher appearance rate constant of the receptor (Δr=57%) and not to a decreased disappearance rate constant (Δk=7%). Northern- and dot-blot analyses of RNA extracted from the cerebral cortex of saline- and reserpine-treated rats (0.25 mg kg−1, s.c., every 48 h for 20 days) revealed that reserpine markedly increased the expression of α2a-adrenoceptor mRNA in the brain (125%). This transcriptional activation of the receptor gene expression appears to be the cellular mechanism by which reserpine induces up-regulation in the density of brain α2-adrenoceptors

  17. Inhibitory effects of omega-3 fatty acids on early brain injury after subarachnoid hemorrhage in rats: Possible involvement of G protein-coupled receptor 120/β-arrestin2/TGF-β activated kinase-1 binding protein-1 signaling pathway.

    PubMed

    Yin, Jia; Li, Haiying; Meng, Chengjie; Chen, Dongdong; Chen, Zhouqing; Wang, Yibin; Wang, Zhong; Chen, Gang

    2016-06-01

    Omega-3 fatty acids have been reported to improve neuron functions during aging and in patients affected by mild cognitive impairment, and mediate potent anti-inflammatory via G protein-coupled receptor 120 (GPR120) signal pathway. Neuron dysfunction and inflammatory response also contributed to the progression of subarachnoid hemorrhage (SAH)-induced early brain injury (EBI). This study was to examine the effects of omega-3 fatty acids on SAH-induced EBI. Two weeks before SAH, 30% Omega-3 fatty acids was administered by oral gavage at 1g/kg body weight once every 24h. Specific siRNA for GPR120 was exploited. Terminal deoxynucleotidyl transferase dUTP nick end labeling, fluoro-Jade B staining, and neurobehavioral scores and brain water content test showed that omega-3 fatty acids effectively suppressed SAH-induced brain cell apoptosis and neuronal degradation, behavioral impairment, and brain edema. Western blot, immunoprecipitation, and electrophoretic mobility shift assays results showed that omega-3 fatty acids effectively suppressed SAH-induced elevation of inflammatory factors, including cyclooxygenase-2, monocyte chemoattractant protein-1, and inducible nitric oxide synthase. In addition, omega-3 fatty acids could inhibit phosphorylation of transforming growth factor β activated kinase-1 (TAK1), MEK4, c-Jun N-terminal kinase, and IkappaB kinase as well as activation of nuclear factor kappa B through regulating GPR120/β-arrestin2/TAK1 binding protein-1 pathway. Furthermore, siRNA-induced GPR120 silencing blocked the protective effects of omega-3 fatty acids. Here, we show that stimulation of GPR120 with omega-3 fatty acids pretreatment causes anti-apoptosis and anti-inflammatory effects via β-arrestin2/TAK1 binding protein-1/TAK1 pathway in the brains of SAH rats. Fish omega-3 fatty acids as part of a daily diet may reduce EBI in an experimental rat model of SAH. PMID:27000704

  18. Insertable Fast-Response Amperometric NO/CO Dual Microsensor: Study of Neurovascular Coupling During Acutely Induced Seizures of Rat Brain Cortex.

    PubMed

    Ha, Yejin; Sim, Jeongeun; Lee, Youngmi; Suh, Minah

    2016-03-01

    This paper reports the fabrication of an insertable amperometric dual microsensor and its application for the simultaneous and fast sensing of NO and CO during acutely induced seizures of living rat brain cortex. NO and CO are important signaling mediators, controlling cerebrovascular tone. The dual NO/CO sensor is prepared based on a dual microelectrode having Au-deposited Pt microdisk (WE1, 76 μm diameter) and Pt black-deposited Pt disk (WE2, 50 μm diameter). The different deposited metals for WE1 and WE2 allow the selective anodic detection of CO at WE1 (+0.2 V vs Ag/AgCl) and that of NO at WE2 (+0.75 V vs Ag/AgCl) with sufficient sensitivity. Fluorinated xerogel coating on this dual electrode provides exclusive selectivity over common biological interferents, along with fast response time. The miniaturized size (end plane diameter < 300 μm) and tapered needle-like sensor geometry make the sensor become insertable into biological tissues. The sensor is applied to simultaneously monitor dynamic changes of NO and CO levels in a living rat brain under acute seizure condition induced by 4-aminopyridine in cortical tissue near the area of seizure induction. In-tissue measurement shows clearly defined patterns of NO/CO changes, directly correlated with observed LFP signal. Current study verifies the feasibility of a newly developed NO/CO dual sensor for real-time fast monitoring of intimately connected NO and CO dynamics. PMID:26855261

  19. Aspartame and the rat brain monoaminergic system.

    PubMed

    Perego, C; De Simoni, M G; Fodritto, F; Raimondi, L; Diomede, L; Salmona, M; Algeri, S; Garattini, S

    1988-12-01

    A high dose of aspartame (APM) was administered to rats to study possible effects on brain monoaminergic systems. APM and its metabolite phenylalanine (Phe) were given orally at doses of 1000 and 500 mg/kg, respectively. Significant increases were seen in brain Phe and tyrosine (Tyr) levels. Two different approaches were used to study monoaminergic systems: whole tissue measurements by HPLC-ED and in vivo voltammetry in freely moving rats. Dopamine, serotonin and their metabolites were taken as indexes of neuronal activity. In spite of the high dose used, no modification was found in monoamines or their metabolites in striatum, hippocampus and nucleus accumbens. PMID:2464204

  20. [Determination of L-dopa and dopamine in rat brain microdialysate by ultra high performance liquid chromatography-tandem mass spectrometry using stable isotope-coded derivatization coupled with dispersive liquid-liquid microextraction].

    PubMed

    Qi, Weimei; Zhao, Xian-en; Qi, Yong; Sun, Zhiwei; Chen, Guang; You, Jinmao; Suo, Yourui

    2015-09-01

    The sensitive detection method of levodopa (L-DOPA) and dopamine (DA) in rat brain microdialysate of Parkinson's disease (PD) is an essential tool for the clinical study and attenuated synergistic drug screening for L-DOPA from traditional Chinese medicines. Using d0/d3-10-methyl-acridone-2-sulfonyl chloride (d0/d3-MASC) as stable isotope derivatization reagent, a novel ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed and validated for L-DOPA and DA by stable isotope- coded derivatization coupled with ultrasonic-assisted dispersive liquid-liquid microextraction (UA-DLLME). d3-MASC (light) and d3-MASC (heavy) were used as derivatization reagents for microdialysate samples and standards, respectively. Mixtures of the two solutions were prepared by UA-DLLME for UHPLC-MS/MS analysis with multiple reaction monitoring (MRM) mode. With d3-MASC heavy derivatives as internal standards for corresponding light derivatives from samples, the stable isotope internal standard quantification for L-DOPA and DA was carried out. The stable derivatives were obtained in aqueous acetonitrile (pH 10.8 sodium carbonate-sodium bicarbonate buffer) at 37 °C for 3.0 min, and then were separated within 2.0 min using gradient elution. Linear range was 0.20-1500.0 nmol/L (R > 0.994). LODs were 0.005 and 0.009 nmol/L for DA and L-DOPA (S/N = 3), respectively. This method was validated, and it showed obvious advantages in comparing with the reported methods in terms of sensitivity, analysis speed and anti-matrix interference. This method has been successfully applied to the study of effect of Shouwu Fang on L-DOPA and DA concentration fluctuations in PD rat brain microdialysate. PMID:26753287

  1. Alcohol induced changes in phosphoinositide signaling system in rat brain

    SciTech Connect

    Pandey, S.; Piano, M.; Schwertz, D.; Davis, J.; Pandey, G. )

    1991-03-11

    Agonist-induced phosphoinositide break down functions as a signal generating system in a manner similar to the C-AMP system. In order to examine if the changes produced by chronic ethanol treatment on membrane lipid composition and metabolism effect the cellular functions of the neuron, the authors have examined the effect of chronic ethanol exposure on norepinephrine (NE) serotonin (5HT) and calcium ionophore (CI) stimulated phosphoinositide (PI) hydrolysis in rat cortical slices. Rats were maintained on liber-decarli diet alcohol and control liquid diet containing isocaloric sucrose substitute for two months. They were then sacrificed and brain was removed for determination of PI turnover. 5HT stimulated {sup 3}H- inositol monophosphate ({sup 3}H-IPI) formation was significantly lower in the cortex of alcohol treated rats as compared to control rats. However, neither CI nor NE stimulated IP1 formation was significantly different from control rats. The results thus indicate that chronic exposure to ethanol decreases 5HT induced PI breakdown in rat cortex. In order to examine if this decrease is related to a decrease in 5HT2 receptors, or decreased in coupling of receptor to the effector pathway, the authors are currently determining the number and affinity of 5HT2 receptors in alcohol treated rats.

  2. Laser scattering by transcranial rat brain illumination

    NASA Astrophysics Data System (ADS)

    Sousa, Marcelo V. P.; Prates, Renato; Kato, Ilka T.; Sabino, Caetano P.; Suzuki, Luis C.; Ribeiro, Martha S.; Yoshimura, Elisabeth M.

    2012-06-01

    Due to the great number of applications of Low-Level-Laser-Therapy (LLLT) in Central Nervous System (CNS), the study of light penetration through skull and distribution in the brain becomes extremely important. The aim is to analyze the possibility of precise illumination of deep regions of the rat brain, measure the penetration and distribution of red (λ = 660 nm) and Near Infra-Red (NIR) (λ = 808 nm) diode laser light and compare optical properties of brain structures. The head of the animal (Rattus Novergicus) was epilated and divided by a sagittal cut, 2.3 mm away from mid plane. This section of rat's head was illuminated with red and NIR lasers in points above three anatomical structures: hippocampus, cerebellum and frontal cortex. A high resolution camera, perpendicularly positioned, was used to obtain images of the brain structures. Profiles of scattered intensities in the laser direction were obtained from the images. There is a peak in the scattered light profile corresponding to the skin layer. The bone layer gives rise to a valley in the profile indicating low scattering coefficient, or frontal scattering. Another peak in the region related to the brain is an indication of high scattering coefficient (μs) for this tissue. This work corroborates the use of transcranial LLLT in studies with rats which are subjected to models of CNS diseases. The outcomes of this study point to the possibility of transcranial LLLT in humans for a large number of diseases.

  3. Genetic influence on brain catecholamines: high brain norepinephrine in salt-sensitive rats

    SciTech Connect

    Iwai, J; Friedman, R; Tassinari, L

    1980-01-01

    Rats genetically sensitive to salt-induced hypertension evinced higher levels of plasma norepinephrine and epinephrine than rats genetically resistant to hypertension. The hypertension-sensitive rats showed higher hypothalamic norepinephrine and lower epinephrine than resistant rats. In response to a high salt diet, brain stem norepinephrine increased in sensitive rats while resistant rats exhibited a decrease on the same diet.

  4. Purified Rabies Vaccine (Suckling Rat Brain Origin)

    PubMed Central

    Lavender, J. F.

    1970-01-01

    A 10% suckling rat brain rabies vaccine free from encephalitogenic activity was prepared and inactivated with 1:8,000 beta-propiolactone (BPL), or ultraviolet light, or a combination of ultraviolet light and BPL, or 1% phenol. Potency was excellent in all samples, with the exception of the phenolized product which was marginal. A purified suckling rat brain (SRB) vaccine prepared by zonal centrifugation and inactivated with 1:8,000 BPL contained about 0.01 the amount of protein nitrogen of the unpurified 10% SRB vaccine. This purified product passed the National Institutes of Health potency test for rabies vaccine after administration of a quantity equivalent to a standard 10% brain suspension. PMID:5456012

  5. Heterogeneous expression of transketolase in rat brain.

    PubMed

    Calingasan, N Y; Sheu, K F; Baker, H; Jung, E H; Paoletti, F; Gibson, G E

    1995-03-01

    Transketolase (TK; EC 2.2.1.1) is a key pentose phosphate shunt enzyme that plays an important role in the production of reducing equivalents and pentose sugars. TK activity declines in the brains of patients with Alzheimer's disease or Wernicke-Korsakoff syndrome, as well as in thiamine-deficient rats. Understanding the role of TK in the pathophysiology of these neurodegenerative conditions requires knowledge of its regional, cellular, and subcellular distribution within the brain. The current study employed in situ hybridization and immunocytochemistry to examine the distribution of TK mRNA and its encoded protein in adult rat brain. TK mRNA and protein were widely distributed throughout the brain. However, they were enriched in selective perikarya in the piriform cortex, nucleus of the diagonal band, red nucleus, dorsal raphe, pontine nucleus, locus coeruleus, trapezoid, inferior olive, and several cranial nerve nuclei. Lower expression of TK mRNA and protein occurred in layer V of cortex, olfactory tubercle, ventral pallidum, medial septal nucleus, hippocampus, thalamic and hypothalamic nuclei, mammillary body, central gray, and the substantia nigra. TK immunoreactivity also occurred in the nuclei of ubiquitously distributed glial cells, as well as ependymal cells. The heterogeneous distribution of TK may reflect a variety of metabolic activities among different brain regions but does not provide a simple molecular explanation for selective cell death in either thiamine deficiency or other conditions where TK is reduced. PMID:7861132

  6. EVALUATION OF PERFLUOROOCTANE SULFONATE (PFOS) IN THE RAT BRAIN

    EPA Science Inventory

    This study examined whether there is a differential distribution of PFOS within the brain, and compares adult rats with neonatal rats at an age when formation of the blood-brain barrier is not yet complete (postnatal day 7). Male and female Sprague-Dawley rats (60-70 day old, 4/...

  7. Secretin: specific binding to rat brain membranes

    SciTech Connect

    Fremeau, R.T. Jr.; Jensen, R.T.; Charlton, C.G.; Miller, R.L.; O'Donohue, T.L.; Moody, T.W.

    1983-08-01

    The binding of (/sup 125/I)secretin to rat brain membranes was investigated. Radiolabeled secretin bound with high affinity (KD . 0.2 nM) to a single class of noninteracting sites. Binding was specific, saturable, and reversible. Regional distribution studies indicated that the specific binding was greatest in the cerebellum, intermediate in the cortex, thalamus, striatum, hippocampus, and hypothalamus, and lowest in the midbrain and medulla/pons. Pharmacological studies indicated that only secretin, but not other peptides, inhibits binding of (/sup 125/I)secretin with high affinity. Also, certain guanine nucleotides inhibited high affinity binding. These data indicate that rat brain membranes possess high affinity binding sites specific for secretin and that with the use of (/sup 125/I) secretin the kinetics, stoichiometry, specificity, and distribution of secretin receptors can be directly investigated.

  8. Regulation of brain aromatase activity in rats

    SciTech Connect

    Roselli, C.E.; Ellinwood, W.E.; Resko, J.A.

    1984-01-01

    The distribution and regulation of aromatase activity in the adult rat brain with a sensitive in vitro assay that measures the amount of /sup 3/H/sub 2/O formed during the conversion of (1 beta-/sup 3/H)androstenedione to estrone. The rate of aromatase activity in the hypothalamus-preoptic area (HPOA) was linear with time up to 1 h, and with tissue concentrations up to 5 mgeq/200 microliters incubation mixture. The enzyme demonstrated a pH optimum of 7.4 and an apparent Michaelis-Menten constant (Km) of 0.04 microns. The greatest amount of aromatase activity was found in amygdala and HPOA from intact male rats. The hippocampus, midbrain tegmentum, cerebral cortex, cerebellum, and anterior pituitary all contained negligible enzymatic activity. Castration produced a significant decrease in aromatase activity in the HPOA, but not in the amygdala or cerebral cortex. The HPOAs of male rats contained significantly greater aromatase activity than the HPOAs of female rats. In females, this enzyme activity did not change during the estrous cycle or after ovariectomy. Administration of testosterone to gonadectomized male and female rats significantly enhanced HPOA aromatase activities to levels approximating those found in HPOA from intact males. Therefore, the results suggest that testosterone, or one of its metabolites, is a major steroidal regulator of HPOA aromatase activity in rats.

  9. Ethanol effects on rat brain phosphoinositide metabolism

    SciTech Connect

    Huang, H.M.

    1987-01-01

    An increase in acidic phospholipids in brain plasma and synaptic plasma membranes upon chronic ethanol administration was observed. Chronic ethanol administration resulted in an increase in {sup 32}P{sub i} incorporation into the acidic phospholipids in synaptosomes. Postdecapitative ischemic treatment resulted rapid degradation of poly-PI in rat brain. However, there was a rapid appearance of IP{sub 2} in ethanol group which indicated a more rapid turnover of IP{sub 3} in the ethanol-treated rats. Carbachol stimulated accumulation of labeled inositol phosphates in brain slices and synaptosomes. Carbachol-stimulated release of IP and IP{sub 2} was calcium dependent and was inhibited by EGTA and atropine. Adenosine triphosphates and 1 mM further enhanced carbachol-induced formation of IP and IP{sub 2}, but showed an increase and a decrease in IP{sub 3} at 1 mM and 0.01 mM, respectively. Guanosine triphosphate at 0.1 mM did not change in labeled IP, but there was a significant increase in labeled IP{sub 2} and decrease in IP{sub 3}. Mn and CMP greatly enhanced incorporation of ({sup 3}H)-inositol into PI, but not into poly-PI labeling in brain synaptosomes. Incubation of brain synaptosomes resulted in a Ca{sup 2+}, time-dependent release of labeled IP. However, the pool of PI labeled through this pathway is not susceptible to carbachol stimulation. When saponin permeabilized synaptosomal preparations were incubated with ({sup 3}H)-inositol-PI or ({sup 14}C)-arachidonoyl-PI, ATP enhanced the formation of labeled IP and DG.

  10. Studies of aluminum in rat brain

    SciTech Connect

    Lipman, J.J.; Brill, A.B.; Som, P.; Jones, K.W.; Colowick, S.; Cholewa, M.

    1985-01-01

    The effects of high aluminum concentrations in rat brains were studied using /sup 14/C autoradiography to measure the uptake of /sup 14/C 2-deoxy-D-glucose (/sup 14/C-2DG) and microbeam proton-induced x-ray emission (microPIXE) with a 20-..mu..m resolution to measure concentrations of magnesium, aluminum, potassium, and calcium. The aluminum was introduced intracisternally in the form of aluminum tartrate (Al-T) while control animals were given sodium tartrate (Na-T). The /sup 14/C was administered intravenously. The animals receiving Al-T developed seizure disorders and had pathological changes that included cerebral cortical atrophy. The results showed that there was a decreased uptake of /sup 14/C-2DG in cortical regions in which increased aluminum levels were measured, i.e., there is a correlation between the aluminum in the rat brain and decreased brain glucose metabolism. A minimum detection limit of about 16 ppM (mass fraction) or 3 x 10/sup 9/ Al atoms was obtained for Al under the conditions employed. 14 refs., 4 figs., 1 tab.

  11. Brain cholecystokinin and nutritional status in rats and mice.

    PubMed Central

    Schneider, B S; Monahan, J W; Hirsch, J

    1979-01-01

    Under certain conditions, exogenously administered cholecystokinin (CCK) or its COOH-terminal octapeptide can terminate feeding and cause behavioral satiety in animals. Furthermore, high concentrations of CCK are normally found in the brains of vertebrate species. It has thus been hypothesized that brain CCK plays a role in the control of appetite. To explore this possibility, a COOH-terminal radioimmunoassay was used to measure concentrations of CCK in the cerebral cortex, hypothalamus, and brain stem of rats and mice after a variety of nutritional manipulations. CCK, mainly in the form of its COOH-terminal octapeptide, was found to appear in rat brain shortly before birth and to increase rapidly in cortex and brain stem throughout the first 5 wk of life. Severe early undernutrition had no effect on the normal pattern of CCK development in rat brain. Adult rats deprived of food for up to 72 h and rats made hyperphagic with highly palatable diets showed no alterations in brain CCK concentrations or distribution of molecular forms of CCK as determined by Sephadex gel filtration of brain extracts. Normal CCK concentrations were also found in the brains of four strains of genetically obese rodents and in the brains of six animals made hyperphagic and obese by surgical or chemical lesioning of the ventromedial hypothalamus. It is concluded that despite extreme variations in the nutritional status of rats and mice, CCK concentrations in major structures of the brain are maintained with remarkable constancy. PMID:500815

  12. Immunochemical characterization of phosphatidylinositol 4-phosphate kinase from rat brain.

    PubMed Central

    van Dongen, C J; Kok, J W; Schrama, L H; Oestreicher, A B; Gispen, W H

    1986-01-01

    Affinity-purified antibodies were used to identify a protein of molecular mass 45 kDa (45 kDa protein) in rat brain cytosol as phosphatidylinositol 4-phosphate (PtdIns4P) kinase. Antibodies were raised in rabbits by immunization with the purified 45 kDa protein. Anti-(45 kDa protein) immunoglobulins were isolated by affinity chromatography of the antiserum on a solid immunosorbent, which was prepared by coupling a soluble rat brain fraction, the DEAE-cellulose pool containing 10-15% 45 kDa protein, to CNBr-activated Sepharose 4B. The purified IgGs were specific for the 45 kDa protein as judged by immunoblot and by immunoprecipitation. The purified anti-(45 kDa protein) IgGs inhibited the enzyme activity of partially purified PtdIns4P kinase, whereas preimmune IgGs were ineffective. Immunoprecipitation of the 45 kDa protein from the partially purified enzyme preparation with the purified IgGs resulted in a concomitant decrease in the amount of 45 kDa protein and in PtdIns4P kinase activity. The amount of 45 kDa protein remaining in the supernatant and the activity of PtdIns4P kinase correlated with a coefficient of r = 0.87. The evidence presented lends further support for the notion that the catalytic activity of PtdIns4P kinase in rat brain cytosol resides in a 45 kDa protein. Images Fig. 1. Fig. 2. PMID:3010943

  13. Mitochondrial dysfunction in aging rat brain following transient global ischemia.

    PubMed

    Xu, Kui; Puchowicz, Michelle A; Sun, Xiaoyan; LaManna, Joseph C

    2008-01-01

    Aged rat brain is more sensitive to reperfusion injury induced by cardiac arrest and resuscitation. The mitochondrial respiratory chain, the major source of free radicals during reperfusion, is likely to be the target of lipid peroxidation. Previous work has shown a higher mortality and lower hippocampal neuronal survival in older rats. 4-hydroxy-2-nonenal (HNE), a major product of lipid peroxidation, was found to be elevated in cortex and brainstem after resuscitation. In this study we investigated the acute changes of mitochondrial function in aging rat brain following cardiac arrest and resuscitation; the effect of an antioxidant, alpha-phenyl-tert-butyl-nitrone (PBN) was also tested. Fischer 344 rats, 6 and 24-month old, were subjected to cardiac arrest (7-10 minutes) and allowed to recover 1 hour after resuscitation. Mitochondria of cortex and brainstem were isolated and assayed for respiratory function. Compared to their respective non-arrested control group, 1h untreated groups (both 6 month and 24 month) had similar state 3 (ADP-stimulated) but higher state 4 (resting state) respiratory rates. The respiratory control ratio (state 3/state 4) of cortex in the 1h untreated group was 26% lower than the non-arrested control group; similar results were found in brainstem. The decreased mitochondrial respiratory function was improved by PBN treatment. HNE-modified mitochondrial proteins were elevated 1h after resuscitation, with an evident change in the aged. Treatment with PBN reduced the elevated HNE production in mitochondria of cortex. The data suggest (i) there is increased sensitivity to lipid peroxidation with aging, (ii) mitochondrial respiratory function related to coupled oxidation decreases following cardiac arrest and resuscitation, and (iii) treatment with antioxidant, such as PBN, reduces the oxidative damage following cardiac arrest and resuscitation. PMID:18290349

  14. Propofol Attenuates Early Brain Injury After Subarachnoid Hemorrhage in Rats.

    PubMed

    Shi, Song-sheng; Zhang, Hua-bin; Wang, Chun-hua; Yang, Wei-zhong; Liang, Ri-sheng; Chen, Ye; Tu, Xian-kun

    2015-12-01

    Our previous studies demonstrated that propofol protects rat brain against focal cerebral ischemia. However, whether propofol attenuates early brain injury after subarachnoid hemorrhage in rats remains unknown until now. The present study was performed to evaluate the effect of propofol on early brain injury after subarachnoid hemorrhage in rats and further explore the potential mechanisms. Sprague-Dawley rats underwent subarachnoid hemorrhage (SAH) by endovascular perforation then received treatment with propofol (10 or 50 mg/kg) or vehicle after 2 and 12 h of SAH. SAH grading, neurological scores, brain water content, Evans blue extravasation, the myeloperoxidase activity, and malondialdehyde (MDA) content were measured 24 h after SAH. Expression of nuclear factor erythroid-related factor 2 (Nrf2), nuclear factor-kappa B (NF-κB) p65, and aquaporin 4 (AQP4) expression in rat brain were detected by Western blot. Expression of cyclooxygenase-2 (COX-2) and matrix metalloproteinase-9 (MMP-9) were determined by reverse transcription-polymerase chain reaction (RT-PCR). Expressions of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) were assessed by ELISA. Neurological scores, brain water content, Evans blue extravasation, the myeloperoxidase activity, and MDA content were significantly reduced by propofol. Furthermore, expression of Nrf2 in rat brain was upregulated by propofol, and expression of NF-κB p65, AQP4, COX-2, MMP-9, TNF-α, and IL-1β in rat brain were attenuated by propofol. Our results demonstrated that propofol improves neurological scores, reduces brain edema, blood-brain barrier (BBB) permeability, inflammatory reaction, and lipid peroxidation in rats of SAH. Propofol exerts neuroprotection against SAH-induced early brain injury, which might be associated with the inhibition of inflammation and lipid peroxidation. PMID:26342279

  15. Kappa opioid receptors stimulate phosphoinositide turnover in rat brain

    SciTech Connect

    Periyasamy, S.; Hoss, W. )

    1990-01-01

    The effects of various subtype-selective opioid agonists and antagonists on the phosphoinositide (PI) turnover response were investigated in the rat brain. The {kappa}-agonists U-50,488H and ketocyclazocine produced a concentration-dependent increase in the accumulation of IP's in hippocampal slices. The other {kappa}-agonists Dynorphin-A (1-13) amide, and its protected analog D(Ala){sup 2}-dynorphin-A (1-13) amide also produced a significant increase in the formation of ({sup 3}H)-IP's, whereas the {mu}-selective agonists (D-Ala{sup 2}-N-Me-Phe{sup 4}-Gly{sup 5}-ol)-enkephalin and morphine and the {delta}-selective agonist (D-Pen{sup 2,5})-enkephalin were ineffective. The increase in IP's formation elicited by U-50,488H was partially antagonized by naloxone and more completely antagonized by the {kappa}-selective antagonists nor-binaltorphimine and MR 2266. The formation of IP's induced by U-50,488H varies with the regions of the brain used, being highest in hippocampus and amygdala, and lowest in striatum and pons-medullar. The results indicate that brain {kappa}- but neither {mu}- nor {delta}- receptors are coupled to the PI turnover response.

  16. TOF-SIMS imaging of lipids on rat brain sections.

    PubMed

    Touboul, David; Brunelle, Alain

    2015-01-01

    Since several decades, secondary ion mass spectrometry (SIMS) coupled to time of flight (TOF) is used for atomic or small inorganic/organic fragments imaging on different materials. With the advent of polyatomic ion sources leading to a significant increase of sensitivity in combination with a reasonable spatial resolution (1-10 μm), TOF-SIMS is becoming a more and more popular analytical platform for MS imaging. Even if this technique is limited to small molecules (typically below 1,000 Da), it offers enough sensitivity to detect and locate various classes of lipids directly on the surface of tissue sections. This chapter is thus dedicated to the TOF-SIMS analysis of lipids in positive and negative ion modes on rat brain tissue sections using a bismuth cluster ion source. PMID:25361663

  17. Preparation of Highly Coupled Rat Heart Mitochondria

    PubMed Central

    Gostimskaya, Irina; Galkin, Alexander

    2010-01-01

    The function of mitochondria in generation of cellular ATP in the process of oxidative phosphorylation is widely recognised. During the past decades there have been significant advances in our understanding of the functions of mitochondria other than the generation of energy. These include their role in apoptosis, acting as signalling organelles, mammalian development and ageing as well as their contribution to the coordination between cell metabolism and cell proliferation. Our understanding of biological processes modulated by mitochondria is based on robust methods for isolation and handling of intact mitochondria from tissues of the laboratory animals. Mitochondria from rat heart is one of the most common preparations for past and current studies of cellular metabolism including studies on knock-out animals. Here we describe a detailed rapid method for isolation of intact mitochondria with a high degree of coupling. Such preparation of rat heart mitochondria is an excellent object for functional and structural research on cellular bioenergetics, transport of biomolecules, proteomic studies and analysis of mitochondrial DNA, proteins and lipids. PMID:20972393

  18. Brain Injury After Intracerebral Hemorrhage in Spontaneously Hypertensive Rats

    PubMed Central

    Wu, Gang; Bao, Xuhui; Xi, Guohua; Keep, Richard; Thompson, B. Gregory; Hua, Ya

    2011-01-01

    Object Hypertension is the main cause of spontaneous intracerebral hemorrhages (ICH), but the effects of hypertension on ICH-induced brain injury have not been well studied. In this study, we examined ICH-induced brain injury in spontaneously hypertensive rats (SHR). Methods This two-part study was performed on 12 weeks old male SHR and Wistar Kyoto (WKY) rats. First, rats received an intracaudate injection of 0.3 units collagenase and hematoma sizes were determined at 24 hours. Second, rats were injected with 100-μL autologous whole blood into the right basal ganglia. Brain edema, neuronal death, ferritin expression, microglia activation, and neurological deficits were examined. Results Hematoma sizes were the same in SHR and WKY rats 24 hours after collagenase injection. SHR had greater neuronal death and neurological deficits after blood injection. ICH also resulted in higher brain ferritin levels and stronger activation of microglia in SHR. However, perihematomal brain edema was same in the SHR and WKY rats. Conclusion Moderate chronic hypertension resulted in more severe ICH-induced neuronal death and neurological deficits, but did not exaggerate hematoma enlargement and perihematomal brain edema in the rat ICH models. PMID:21294617

  19. 26Al uptake and accumulation in the rat brain

    NASA Astrophysics Data System (ADS)

    Yumoto, S.; Nagai, H.; Imamura, M.; Matsuzaki, H.; Hayashi, K.; Masuda, A.; Kumazawa, H.; Ohashi, H.; Kobayashi, K.

    1997-03-01

    To investigate the cause of Alzheimer's disease (senile dementia), 26Al incorporation in the rat brain was studied by accelerator mass spectrometry (AMS). When 26Al was injected into healthy rats, a considerable amount of 26Al entered the brain (cerebrum) through the blood-brain barrier 5 days after a single injection, and the brain 26Al level remained almost constant from 5 to 270 days. On the other hand, the level of 26Al in the blood decreased remarkably 75 days after injection. Approximately 89% of the 26Al taken in by the brain cell nuclei bound to chromatin. This study supports the theory that Alzheimer's disease is caused by irreversible accumulation of aluminium (Al) in the brain, and brain cell nuclei.

  20. Aluminium toxicity in the rat liver and brain

    NASA Astrophysics Data System (ADS)

    Yumoto, S.; Ohashi, H.; Nagai, H.; Kakimi, S.; Ishikawa, A.; Kobayashi, K.; Ogawa, Y.; Ishii, K.

    1993-04-01

    To investigate the etiology of Alzheimer's disease, we examined the brain and liver tissue uptake of aluminium 5-75 days after aluminium injection into healthy rats. Ten days after the last injection, Al was detected in the brain and the brain cell nuclei by particle-induced X-ray emission (PIXE) analysis. Al was also demonstrated in the liver and the liver cell nuclei by PIXE analysis and electron energy loss spectrometry (EELS). The morphological changes of the rat brain examined 75 days after the injection were similar to those which have been reportedly observed in the brain of patients with Alzheimer's disease. These results support the theory that Alzheimer's disease is caused by irreversible accumulation of aluminium in the brain, as well as in the nuclei of brain cells.

  1. Dexmedetomidine Postconditioning Reduces Brain Injury after Brain Hypoxia-Ischemia in Neonatal Rats.

    PubMed

    Ren, Xiaoyan; Ma, Hong; Zuo, Zhiyi

    2016-06-01

    Perinatal asphyxia can lead to death and severe disability. Brain hypoxia-ischemia (HI) injury is the major pathophysiology contributing to death and severe disability after perinatal asphyxia. Here, seven-day old Sprague-Dawley rats were subjected to left brain HI. Dexmedetomidine was given intraperitoneally after the brain HI. Yohimbine or atipamezole, two α2 adrenergic receptor antagonists, were given 10 min before the dexmedetomidine injection. Neurological outcome was evaluated 7 or 28 days after the brain HI. Frontal cerebral cortex was harvested 6 h after the brain HI. Left brain HI reduced the left cerebral hemisphere weight assessed 7 days after the brain HI. This brain tissue loss was dose-dependently attenuated by dexmedetomidine. Dexmedetomidine applied within 1 h after the brain HI produced this effect. Dexmedetomidine attenuated the brain HI-induced brain tissue and cell loss as well as neurological and cognitive dysfunction assessed from 28 days after the brain HI. Dexmedetomidine postconditioning-induced neuroprotection was abolished by yohimbine or atipamezole. Brain HI increased tumor necrosis factor α and interleukin 1β in the brain tissues. This increase was attenuated by dexmedetomidine. Atipamezole inhibited this dexmedetomidine effect. Our results suggest that dexmedetomidine postconditioning reduces HI-induced brain injury in the neonatal rats. This effect may be mediated by α2 adrenergic receptor activation that inhibits inflammation in the ischemic brain tissues. PMID:26932203

  2. Increased sensitivity to transient global ischemia in aging rat brain.

    PubMed

    Xu, Kui; Sun, Xiaoyan; Puchowicz, Michelle A; LaManna, Joseph C

    2007-01-01

    Transient global brain ischemia induced by cardiac arrest and resuscitation (CAR) results in reperfusion injury associated with oxidative stress. Oxidative stress is known to produce delayed selective neuronal cell loss and impairment of brainstem function, leading to post-resuscitation mortality. Levels of 4-hydroxy-2-nonenal (HNE) modified protein adducts, a marker of oxidative stress, was found to be elevated after CAR in rat brain. In this study we investigated the effects of an antioxidant, alpha-phenyl-tert-butyl-nitrone (PBN) on the recovery following CAR in the aged rat brain. Male Fischer 344 rats (6, 12 and 24-month old) underwent 7-minute cardiac arrest before resuscitation. Brainstem function was assessed by hypoxic ventilatory response (HVR) and HNE-adducts were measured by western blot analysis. Our data showed that in the 24-month old rats, overall survival rate, hippocampal CAl neuronal counts and HVR were significantly reduced compared to the younger rats. With PBN treatment, the recovery was improved in the aged rat brain, which was consistent with reduced HNE adducts in brain following CAR. Our data suggest that aged rats are more vulnerable to oxidative stress insult and treatment with PBN improves the outcome following reperfusion injury. The mechanism of action is most likely through the scavenging of reactive oxygen species resulting in reduced lipid peroxidation. PMID:17727265

  3. IN VITRO COMPARISON OF RAT AND CHICKEN BRAIN NEUROTOXIC ESTERASE

    EPA Science Inventory

    A systematic comparison was undertaken to characterize neurotoxic esterase (NTE) from rat and chicken brain in terms of inhibitor sensitivities, pH optima, and molecular weights. Paraoxon titration of phenyl valerate (PV)-hydrolyzing carboxylesterased showed that rat esterases we...

  4. Functional mitochondrial analysis in acute brain sections from adult rats reveals mitochondrial dysfunction in a rat model of migraine

    PubMed Central

    Fried, Nathan T.; Moffat, Cynthia; Seifert, Erin L.

    2014-01-01

    Mitochondrial dysfunction has been implicated in many neurological disorders that only develop or are much more severe in adults, yet no methodology exists that allows for medium-throughput functional mitochondrial analysis of brain sections from adult animals. We developed a technique for quantifying mitochondrial respiration in acutely isolated adult rat brain sections with the Seahorse XF Analyzer. Evaluating a range of conditions made quantifying mitochondrial function from acutely derived adult brain sections from the cortex, cerebellum, and trigeminal nucleus caudalis possible. Optimization of this technique demonstrated that the ideal section size was 1 mm wide. We found that sectioning brains at physiological temperatures was necessary for consistent metabolic analysis of trigeminal nucleus caudalis sections. Oxygen consumption in these sections was highly coupled to ATP synthesis, had robust spare respiratory capacities, and had limited nonmitochondrial respiration, all indicative of healthy tissue. We demonstrate the effectiveness of this technique by identifying a decreased spare respiratory capacity in the trigeminal nucleus caudalis of a rat model of chronic migraine, a neurological disorder that has been associated with mitochondrial dysfunction. This technique allows for 24 acutely isolated sections from multiple brain regions of a single adult rat to be analyzed simultaneously with four sequential drug treatments, greatly advancing the ability to study mitochondrial physiology in adult neurological disorders. PMID:25252946

  5. Brain Volume Determination in Subarachnoid Hemorrhage Using Rats.

    PubMed

    Lekic, Tim; Hardy, Maurice; Fujii, Mutsumi; McBride, Devin W; Zhang, John H

    2016-01-01

    Brain edema is routinely measured using the wet-dry method. Volume, however, is the sum total of all cerebral tissues, including water. Therefore, volumetric change following injury may not be adequately quantified using percentage of edema. We thus tested the hypothesis that dried brains can be reconstituted with water and then re-measured to determine the actual volume. Subarachnoid hemorrhage (SAH) was induced by endovascular perforation in adult male Sprague-Dawley rats (n = 30). Animals were euthanized at 24 and 72 h after evaluation of neurobehavior for determination of brain water content. Dried brains were thereafter reconstituted with equal parts of water (lost from brain edema) and centrifuged to remove air bubbles. The total volume was quantified using hydrostatic (underwater) physics principles that 1 ml water (mass) = 1 cm(3) (volume). The amount of additional water needed to reach a preset level marked on 2-ml test tubes was added to that lost from brain edema, and from the brain itself, to determine the final volume. SAH significantly increased both brain water and volume while worsening neurological function in affected rats. Volumetric measurements demonstrated significant brain swelling after SAH, in addition to the brain edema approach. This modification of the "wet-dry" method permits brain volume determination using valuable post hoc dried brain tissue. PMID:26463930

  6. Transcranial Photoacoustic Measurements of Cold-Injured Brains in Rats

    NASA Astrophysics Data System (ADS)

    Ueda, Yoshinori; Sato, Shunichi; Hasegawa, Makoto; Nawashiro, Hiroshi; Saitoh, Daizoh; Shima, Katsuji; Ashida, Hiroshi; Obara, Minoru

    2005-09-01

    We performed transcranial photoacoustic measurements of cold-injured brains in rats. Before inducing injury, a signal peak was observed at two locations corresponding to the surfaces of the skull and brain, while after injury, a third peak appeared at a location corresponding to the back surface of the skull; the third peak was found to be caused by subdural hematoma. The signal peak for the brain surface shifted to a deeper region with elapse of time after injury, indicating deformation of the brain. These findings suggest that small hemorrhage and morphological change of the brain can be transcranially detected by photoacoustic measurement.

  7. Anticonvulsant compounds and 5-hydroxytryptamine in rat brain

    PubMed Central

    Bonnycastle, D. D.; Giarman, N. J.; Paasonen, M. K.

    1957-01-01

    In rats, a series of anticonvulsant compounds have been shown to cause a significant elevation of brain 5-hydroxytryptamine (5-HT) levels in comparison with control values. This increase in 5-HT only occurred in brain tissue and was not observed in spleen, upper small intestine or blood. Elevation of brain levels of 5-HT by iproniazid (Marsilid) or 5-hydroxytryptophan failed to give protection against the convulsant or lethal action of lept zol (75 mg./kg.). PMID:13446378

  8. Actin purification from a gel of rat brain extracts.

    PubMed

    Levilliers, N; Peron-Renner, M; Coffe, G; Pudles, J

    1984-01-01

    Actin, 99% pure, has been recovered from rat brain with a high yield (greater than 15 mg/100 g brain). We have shown that: 1. a low ionic strength extract from rat brain tissue is capable of giving rise to a gel; 2. actin is the main gel component and its proportion is one order of magnitude higher than in the original extract; 3. actin can be isolated from this extract by a three-step procedure involving gelation, dissociation of the gel in 0.6 M KCl, followed by one or two depolymerization-polymerization cycles. PMID:6529588

  9. Brain-to-Brain coupling: A mechanism for creating and sharing a social world

    PubMed Central

    Hasson, Uri; Ghazanfar, Asif A.; Galantucci, Bruno; Garrod, Simon; Keysers, Christian

    2012-01-01

    Cognition materializes in an interpersonal space. The emergence of complex behaviors requires the coordination of actions among individuals according to a shared set of rules. Despite the central role of other individuals in shaping our minds, most cognitive studies focus on processes that occur within a single individual. We call for a shift from a single-brain to a multi-brain frame of reference. We argue that in many cases the neural processes in one brain are coupled to the neural processes in another brain via the transmission of a signal through the environment. Brain-to-brain coupling constrains and simplifies the actions of each individual in a social network, leading to complex joint behaviors that could not have emerged in isolation. PMID:22221820

  10. Effects of photoradiation therapy on normal rat brain

    SciTech Connect

    Cheng, M.K.; McKean, J.; Boisvert, D.; Tulip, J.; Mielke, B.W.

    1984-12-01

    Laser photoradiation of the brain via an optical fiber positioned 5 mm above a burr hole was performed after the injection of hematoporphyrin derivative (HpD) in 33 normal rats and 6 rats with an intracerebral glioma. Normal rats received HpD, 5 or 10 mg/kg of body weight, followed by laser exposure at various doses or were exposed to a fixed laser dose after the administration of HpD, 2.5 to 20 mg/kg. One control group received neither HpD nor laser energy, and another was exposed to laser energy only. The 6 rats bearing an intracranial 9L glioma were treated with HpD, 5 mg/kg, followed by laser exposure at various high doses. The temperature in the cortex or tumor was measured with a probe during laser exposure. The rats were killed 72 hours after photoradiation, and the extent of necrosis of cerebral tissue was measured microscopically. In the normal rats, the extent of brain damage correlated with increases in the dose of both the laser and the HpD. In all 6 glioma-bearing rats, the high laser doses produced some focal necrosis in the tumors but also damaged adjacent normal brain tissue. The authors conclude that damage to normal brain tissue may be a significant complication of high dose photoradiation therapy for intracranial tumors.

  11. In vitro comparison of rat and chicken brain neurotoxic esterase

    SciTech Connect

    Novak, R.; Padilla, S.

    1986-04-01

    A systematic comparison was undertaken to characterize neurotoxic esterase (NTE) from rat and chicken brain in terms of inhibitor sensitivities, pH optima, and molecular weights. Paraoxon titration of phenyl valerate (PV)-hydrolyzing carboxylesterases showed that rat esterases were more sensitive than chicken to paraoxon inhibition at concentrations less than or equal to microM and superimposable with chicken esterases at concentrations of 2.5-1000 microM. Mipafox titration of the paraoxon-resistant esterases at a fixed paraoxon concentration of 100 microM (mipafox concentration: 0-1000 microM) resulted in a mipafox I50 of 7.3 microM for chicken brain NTE and 11.6 microM for rat brain NTE. NTE (i.e., paraoxon-resistant, mipafox-sensitive esterase activity) comprised 80% of chicken and 60% of rat brain paraoxon-resistant activity with the specific activity of chicken brain NTE approximately twice that of rat brain NTE. The pH maxima for NTE from both species was similar showing broad, slightly alkaline optima from pH 7.9 to 8.6. (/sup 3/H)Diisopropyl phosphorofluoridate (DFP)-labeled NTE from the brains of both species had an apparent mol wt of 160,000 measured by sodium dodecyl sulfate polyacrylamide gel electrophoresis. In conclusion, NTE from both species was very similar, with the mipafox I50 for rat NTE within the range of reported values for chicken and human NTE, and the inhibitor parameters of the chicken NTE assay were applicable for the rat NTE assay.

  12. Transport of 3-hydroxybutyrate by cultured rat brain astrocytes

    SciTech Connect

    McKenna, M.C.; Tildon, J.T.; Stevenson, J.H.; Couto, R.; Caprio, F.J. )

    1990-02-26

    Studies by a number of investigators have shown that 3-hydroxybutyrate is a preferred energy substrate for brain during early development. Since recent studies by the authors group suggest that the utilization of oxidizable substrates by brain may be regulated in part by transport across the plasma membrane, the authors investigated the transport of ({sup 3}H) D- and L-3-hydroxybutyrate and 3-hydroxy-(3-{sup 14}C) butyrate by primary cultures of rat brain astrocytes. The data is consistent with the hypothesis that 3-hydroxybutyrate is taken up into cultured rat brain astrocytes by both diffusion and a carrier mediated transport system, and further support the concept that transport at the cellular level contributes to the regulation of substrate utilization by brain cells.

  13. Brain glucose content in fetuses of ethanol-fed rats

    SciTech Connect

    Pullen, G.; Singh, S.P.; Snyder, A.K.; Hoffen, B.

    1986-03-01

    The authors have previously demonstrated impaired placental glucose transfer and fetal hypoglycemia in association with ethanol ingestion by pregnant rats. The present study examines the relationship between glucose availability and fetal brain growth under the same conditions. Rats (EF) were fed ethanol (30% of caloric intake) in liquid diet throughout gestation. Controls received isocaloric diet without ethanol by pair-feeding (PF) or ad libitum (AF). On the 22nd day of gestation fetuses were obtained by cesarean section. Fetal brains were removed and freeze-clamped. Brain weight was significantly reduced (p < 0.001) by maternal ethanol ingestion (206 +/- 2, 212 +/- 4 and 194 +/- 2 mg in AF, FP and EF fetuses respectively). Similarly, fetal brain glucose content was lower (p < 0.05) in the EF group (14.3 +/- 0.9 mmoles/g dry weight) than in the PF (18.6 +/- 1.0) or the AF (16.2 +/- 0.9) groups. The protein: DNA ratio, an indicator of cell size, correlated positively (r = 0.371, p < 0.005) with brain glucose content. In conclusion, maternal ethanol ingestion resulted in lower brain weight and reduced brain glucose content. Glucose availability may be a significant factor in the determination of cell size in the fetal rat brain.

  14. Cocaine disposition in discrete regions of rat brain.

    PubMed

    Javaid, J I; Davis, J M

    1993-05-01

    It has been proposed that various effects of psychoactive drugs on the central nervous system may be related to the capacity of the drug to selectively concentrate in specific regions of the brain. In rat brain, cocaine effects on striatal and nucleus accumbens dopaminergic systems show quantitative differences. However, the disposition of cocaine in various brain regions has not been reported. In the present studies we examined the cocaine concentrations over time in serum and discrete brain regions of the rat after single intraperitoneal (i.p.) injection. At different time points (5, 10, 20, 30, 60, 120, and 240 min) after i.p. injection of cocaine hydrochloride (10 mg kg-1, free base) the rats were decapitated and cocaine in serum and various brain regions was quantitated by a specific gas liquid chromatographic method. There was large inter-individual variability in different rats at each time-point. The disposition pattern of cocaine in rats after i.p. administration was similar to that observed in humans after intranasal administration. Initial absorption rate was rapid and, on average, the peak levels of cocaine were achieved in 10 min. The cocaine levels remained relatively high over the next 50 min indicating continual absorption, and then declined with a rate such that the levels 4 h after cocaine administration were undetectable in most of the animals. The overall changes in cocaine levels in various brain regions paralleled the serum concentrations. The area under the cocaine concentration-time curve (AUC) revealed more than three-fold differences in cocaine accumulation in various brain regions. This unequal disposition of cocaine may be responsible in part for differential biochemical effects in different brain regions. PMID:8499585

  15. Brain perfusion in acute and chronic hyperglycemia in rats

    SciTech Connect

    Kikano, G.E.; LaManna, J.C.; Harik, S.I. )

    1989-08-01

    Recent studies show that acute and chronic hyperglycemia cause a diffuse decrease in regional cerebral blood flow and that chronic hyperglycemia decreases the brain L-glucose space. Since these changes can be caused by a decreased density of perfused brain capillaries, we used 30 adult male Wistar rats to study the effect of acute and chronic hyperglycemia on (1) the brain intravascular space using radioiodinated albumin, (2) the anatomic density of brain capillaries using alkaline phosphatase histochemistry, and (3) the fraction of brain capillaries that are perfused using the fluorescein isothiocyanate-dextran method. Our results indicate that acute and chronic hyperglycemia do not affect the brain intravascular space nor the anatomic density of brain capillaries. Also, there were no differences in capillary recruitment among normoglycemic, acutely hyperglycemic, and chronically hyperglycemic rats. These results suggest that the shrinkage of the brain L-glucose space in chronic hyperglycemia is more likely due to changes in the blood-brain barrier permeability to L-glucose.

  16. Neuropeptide Y receptors in rat brain: autoradiographic localization

    SciTech Connect

    Martel, J.C.; St-Pierre, S.; Quirion, R.

    1986-01-01

    Neuropeptide Y (NPY) receptor binding sites have been characterized in rat brain using both membrane preparations and receptor autoradiography. Radiolabelled NPY binds with high affinity and specificity to an apparent single class of sites in rat brain membrane preparations. The ligand selectivity pattern reveals strong similarities between central and peripheral NPY receptors. NPY receptors are discretely distributed in rat brain with high densities found in the olfactory bulb, superficial layers of the cortex, ventral hippocampus, lateral septum, various thalamic nuclei and area postrema. The presence of high densities of NPY and NPY receptors in such areas suggests that NPY could serve important functions as a major neurotransmitter/neuromodulator in the central nervous system.

  17. Resting-State Functional Connectivity of the Rat Brain

    PubMed Central

    Pawela, Christopher P.; Biswal, Bharat B.; Cho, Younghoon R.; Kao, Dennis S.; Li, Rupeng; Jones, Seth R.; Schulte, Marie L.; Matloub, Hani S.; Hudetz, Anthony G.; Hyde, James S.

    2008-01-01

    Regional-specific average time courses of spontaneous fluctuations in blood oxygen level dependent (BOLD) MRI contrast at 9.4T in lightly anesthetized resting rat brain are formed, and correlation coefficients between time course pairs are interpreted as measures of connectivity. A hierarchy of regional pairwise correlation coefficients (RPCCs) is observed, with the highest values found in the thalamus and cortex, both intra- and interhemisphere, and lower values between cortex and thalamus. Independent sensory networks are distinguished by two methods: data driven, where task activation defines regions of interest (ROI), and hypothesis driven, where regions are defined by the rat histological atlas. Success in these studies is attributed in part to the use of medetomidine hydrochloride (Domitor) for anesthesia. Consistent results in two different rat-brain systems, the sensorimotor and visual, strongly support the hypothesis that resting-state BOLD fluctuations are conserved across mammalian species and can be used to map brain systems. PMID:18429028

  18. The Extended Mind: Coupling Environment and Brain

    NASA Astrophysics Data System (ADS)

    Vrobel, Susie

    2010-11-01

    This paper describes embodiment and cognitive extension as examples of strong anticipation as defined by Dubois. Clark and Chalmers formulated a thesis which states that parts of the environment, if coupled successfully, can become part of the extended mind. This coupling, be it deliberate or unintentional, shifts the observer-world boundary outwards when the observer encompasses parts of his environment. The resulting extended observer forms a new systemic whole, which consists of both the assimilated context and the recalibrated version of the original observer. Recalibration occurs when conditioning and adaptation lead to corresponding changes on the neural level, for instance, when an agent compensates for delays in a control loop. Plasticity is a prerequisite for any successful incorporation of external structures. However, uncoupled parts of the observer must remain inviolate in order to preserve the boundary. Neither the extended mind nor the core observer are absolute concepts. Depending on whether we focus on local-scale interactions or on large-scale behaviour, boundaries are formed at different interfacial cuts, which lead to either an endo- or an exo-perspective or endo- or exo-anticipation, respectively. For biological extended agents which undergo a transition from exo- to endo-states, a tell-tale sign of a successful exo-endo transition is invisibility. This invisibility occurs when the agent is no longer aware of the delay originally introduced into the control loop by the assimilated part of the environment. Explaining the world in terms of effective causality is not sufficient to account for extended minds. The latter require explanations in terms of final causation. For extended minds, this ordering principle comes in the shape of nested hierarchical layers. The interfaces of these layers may have merged for an endo-observer, whereas an exo-observer can make out the detailed structure, including artificially introduced delays. A sufficient

  19. Hydrophilic solute transport across the rat blood-brain barrier

    SciTech Connect

    Lucchesi, K.J.

    1987-01-01

    Brain capillary permeability-surface area products (PS) of hydrophilic solutes ranging in size from 180 to 5,500 Daltons were measured in rats according to the method of Ohno, Pettigrew and Rapoport. The distribution volume of 70 KD dextran at 10 minutes after i.v. injection was also measured to determine the residual volume of blood in brain tissue at the time of sacrifice. Small test solutes were injected in pairs in order to elucidate whether their transfer into the brain proceeds by diffusion through water- or lipid-filled channels or by vesicular transport. This issue was examined in rats whose blood-brain barrier (BBB) was presumed to be intact (untreated) and in rats that received intracarotid infusions to open the BBB (isosmotic salt (ISS) and hyperosmolar arabinose). Ohno PS values of {sup 3}H-inulin and {sup 14}C-L-glucose in untreated rats were found to decrease as the labelling time was lengthened. This was evidence that a rapidly equilibrating compartment exists between blood and brain that renders the Ohno two-compartment model inadequate for computing true transfer rate constants. When the data were reanalyzed using a multi-compartment graphical analysis, solutes with different molecular radii were found to enter the brain at approximately equal rates. Furthermore, unidirectional transport is likely to be initiated by solute adsorption to a glycocalyx coat on the luminal surface of brain capillary endothelium. Apparently, more inulin than L-glucose was adsorbed, which may account for its slightly faster transfer across the BBB. After rats were treated with intracarotid infusions of ISS or hyperosmolar arabinose, solute PS values were significantly increased, but the ratio of PS for each of the solute pairs approached that of their free-diffusion coefficients.

  20. Silica stationary phase-based on-line sample enrichment coupled with LC-MS/MS for the quantification of dopamine, serotonin and their metabolites in rat brain microdialysates.

    PubMed

    Kim, Minjeong; Lee, Jin-Gyeom; Yang, Chae Ha; Lee, Sooyeun

    2016-06-01

    Accurate measurement of trace levels of endogenous compounds remains challenging despite advancements in analytical technologies. In particular, monoamine neurotransmitters such as dopamine (DA) and serotonin (5-HT) are polar compounds with low molecular weights, which complicates the optimization of retention and detection on liquid chromatography-mass spectrometry (LC-MS). Microdialysis is an important sampling technique to collect extracellular fluid from the brain of living animals. However, the very low basal concentrations of the neurotransmitters, small sample volume (maximum 30 μL) and the absence of matrix-matching calibrators are limitations of a microdialysate as an analytical sample. In the present study, an LC-MS/MS method was developed and fully validated for the quantification of DA, 5-HT and their main metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA), in microdialysates from the rat nucleus accumbens shell. To improve the method sensitivity and accuracy, on-line sample enrichment using silica stationary phase was employed, before which any other sample pretreatment was not performed. The validation results proved the method to be selective, sensitive, accurate and precise, with acceptable linearity within calibration ranges. The lower limits of quantification were 0.025, 0.1, 0.5, 25 and 2.5 ng/mL for 5-HT, DA, 5-HIAA, HVA and DOPAC, respectively. This is a powerful analytical method to determine endogenous concentrations of those compounds in microdialysates from the rat nucleus accumbens and will be very useful to further study on the pathophysiological functions of monoamine neurotramsmitters in vivo. PMID:27155302

  1. Castration affects male rat brain opiate receptor content.

    PubMed

    Hahn, E F; Fishman, J

    1985-07-01

    We previously reported that saturable stereospecific binding of [3H]-naltrexone in rat brain homogenates prepared from castrated male rats was greater than the corresponding binding in intact animals. We now report that we have replicated these results and that the difficulty of other investigators in observing these differences is due to methodological factors. Specifically, when samples were filtered individually and rapidly, differences between castrated and intact rats were maintained. The increase in binding was also observed when tissues were washed to remove endogenous opioids prior to incubation, when [3H]-naloxone was used as the ligand, and when various antagonists were used as displacers in the radioreceptor assay. PMID:2991795

  2. The metabolism of malate by cultured rat brain astrocytes

    SciTech Connect

    McKenna, M.C.; Tildon, J.T.; Couto, R.; Stevenson, J.H.; Caprio, F.J. )

    1990-12-01

    Since malate is known to play an important role in a variety of functions in the brain including energy metabolism, the transfer of reducing equivalents and possibly metabolic trafficking between different cell types; a series of biochemical determinations were initiated to evaluate the rate of 14CO2 production from L-(U-14C)malate in rat brain astrocytes. The 14CO2 production from labeled malate was almost totally suppressed by the metabolic inhibitors rotenone and antimycin A suggesting that most of malate metabolism was coupled to the electron transport system. A double reciprocal plot of the 14CO2 production from the metabolism of labeled malate revealed biphasic kinetics with two apparent Km and Vmax values suggesting the presence of more than one mechanism of malate metabolism in these cells. Subsequent experiments were carried out using 0.01 mM and 0.5 mM malate to determine whether the addition of effectors would differentially alter the metabolism of high and low concentrations of malate. Effectors studied included compounds which could be endogenous regulators of malate metabolism and metabolic inhibitors which would provide information regarding the mechanisms regulating malate metabolism. Both lactate and aspartate decreased 14CO2 production from malate equally. However, a number of effectors were identified which selectively altered the metabolism of 0.01 mM malate including aminooxyacetate, furosemide, N-acetylaspartate, oxaloacetate, pyruvate and glucose, but had little or no effect on the metabolism of 0.5 mM malate. In addition, alpha-ketoglutarate and succinate decreased 14CO2 production from 0.01 mM malate much more than from 0.5 mM malate. In contrast, a number of effectors altered the metabolism of 0.5 mM malate more than 0.01 mM. These included methionine sulfoximine, glutamate, malonate, alpha-cyano-4-hydroxycinnamate and ouabain.

  3. Voltametric assessment of brain nitric oxide during heatstroke in rats.

    PubMed

    Canini, F; Bourdon, L; Cespuglio, R; Buguet, A

    1997-08-01

    Anesthetized rats exposed to a high ambient temperature develop heatstroke with brain ischemia. Since nitric oxide (NO) plays an important role during normothermic ischemia, its cortical and cerebellar production were continuously assessed in pentobarbital anesthetized rats exposed to heat by using differential pulsed voltammetry. After 60 min at thermoneutrality, the rats were submitted to an ambient temperature of 40 degrees C until death. After 60 min in the heat, the rats were injected intraperitoneally with saline, MK801 (1 mg.kg(-1)), an antagonist of N-methyl-D-aspartate (NMDA) receptors, or L-arginine p-nitroanilide (L-ANA; 100 mg.kg(-1)), an inhibitor of NO synthase. Just before death, a 70% increase in NO production was observed in both the cerebellum and the cortex of saline-treated rats. The cortical increase in NO was not modified by MK801 while the NO signal was suppressed by L-ANA. PMID:9291142

  4. Regulation of atrial natriuretic peptide receptors in the rat brain

    SciTech Connect

    Saavedra, J.M.

    1987-06-01

    We have studied the localization, kinetics, and regulation of receptors for the circulating form of the atrial natriuretic peptide (ANP; 99-126) in the rat brain. Quantitative autoradiographic techniques and a /sup 125/I-labeled ligand, /sup 125/I-ANP (99-126), were employed. After in vitro autoradiography, quantification was achieved by computerized microdensitometry followed by comparison with /sup 125/I-standards. ANP receptors were discretely localized in the rat brain, with the highest concentrations in circumventricular organs, the choroid plexus, and selected hypothalamic nuclei involved in the production of the antidiuretic hormone vasopressin and in blood-pressure control. Spontaneously (genetic) hypertensive rats showed much lower numbers of ANP receptors than normotensive controls in the subfornical organ, the area postrema, the nucleus of the solitary tract, and the choroid plexus. These changes are in contrast to those observed for receptors of angiotensin II, another circulating peptide with actions opposite to those of ANP. Under conditions of acute dehydration after water deprivation, as well as under conditions of chronic dehydration such as those present in homozygous Brattleboro rats, there was an up-regulation of ANP receptors in the subfornical organ. Our results indicate that in the brain, circumventricular organs contain ANP receptors which could respond to variations in the concentration of circulating ANP. In addition, brain areas inside the blood-brain barrier contain ANP receptors probably related to the endogenous, central ANP system. The localization of ANP receptors and the alterations in their regulation present in genetically hypertensive rats and after dehydration indicate that brain ANP receptors are probably related to fluid regulation, including the secretion of vasopressin, and to cardiovascular function.

  5. Brain microsomal metabolism of phencyclidine in male and female rats.

    PubMed

    Laurenzana, E M; Owens, S M

    1997-05-01

    These studies examined the microsomal brain metabolism of phencyclidine (PCP) in male and female Sprague-Dawley rats. Several monohydroxylated metabolites of PCP were detected including cis- and trans-1-(1-phenyl-4-hydroxycyclohexyl)piperidine (c-PPC and t-PPC) and 1-(1-phenylcyclohexyl)-4-hydroxypiperidine (PCHP). The in vitro formation of these metabolites required NADPH and was inhibited by carbon monoxide. c-PPC was formed in the male and female brain microsomes at rates of 7.1 +/- 1.3 and 5.7 +/- 1.1 fmol/min per mg, respectively, while t-PPC was formed at rates of 16.2 +/- 3.3 and 16.5 +/- 4.2 fmol/min per mg. PCHP had the highest formation rate at 50.7 +/- 8.9 and 48.2 +/- 8.8 fmol/min per mg, respectively. Although previous studies with rat liver microsomes find higher levels of PCP metabolism in male rats and the formation of an irreversibly bound metabolite in male rats, the present study of brain metabolism found no sex differences in brain metabolism. The formation of PCP metabolites in male rat livers is at least partially mediated by the male-specific isozyme CYP2C11, and possibly CYP2D1. Nevertheless, the formation of the major brain metabolite, PCHP, was not inhibited by an anti-CYP2C11 or an anti-CYP2D6 antibody. However, PCHP formation was inhibited by drug inhibitors of CYP2D1-mediated metabolism, suggesting the involvement of a CYP2D isoform. These data indicate brain metabolism of PCP is significant, but unlike the liver it is not sexually dimorphic. PMID:9187340

  6. The Brain Metabolome of Male Rats across the Lifespan

    PubMed Central

    Zheng, Xiaojiao; Chen, Tianlu; Zhao, Aihua; Wang, Xiaoyan; Xie, Guoxiang; Huang, Fengjie; Liu, Jiajian; Zhao, Qing; Wang, Shouli; Wang, Chongchong; Zhou, Mingmei; Panee, Jun; He, Zhigang; Jia, Wei

    2016-01-01

    Comprehensive and accurate characterization of brain metabolome is fundamental to brain science, but has been hindered by technical limitations. We profiled the brain metabolome in male Wistar rats at different ages (day 1 to week 111) using high-sensitivity and high-resolution mass spectrometry. Totally 380 metabolites were identified and 232 of them were quantitated. Compared with anatomical regions, age had a greater effect on variations in the brain metabolome. Lipids, fatty acids and amino acids accounted for the largest proportions of the brain metabolome, and their concentrations varied across the lifespan. The levels of polyunsaturated fatty acids were higher in infancy (week 1 to week 3) compared with later ages, and the ratio of omega-6 to omega-3 fatty acids increased in the aged brain (week 56 to week 111). Importantly, a panel of 20 bile acids were quantitatively measured, most of which have not previously been documented in the brain metabolome. This study extends the breadth of the mammalian brain metabolome as well as our knowledge of functional brain development, both of which are critically important to move the brain science forward. PMID:27063670

  7. Acetate Transport and Utilization in the Rat Brain

    PubMed Central

    Deelchand, Dinesh K.; Shestov, Alexander A.; Koski, Dee M.; Uğurbil, Kâmil; Henry, Pierre-Gilles

    2009-01-01

    Acetate, a glial-specific substrate, is an attractive alternative to glucose for the study of neuronal-glial interactions. The present study investigates the kinetics of acetate uptake and utilization in the rat brain in vivo during infusion of [2-13C]acetate using NMR spectroscopy. When plasma acetate concentration was increased, the rate of brain acetate utilization (CMRace) increased progressively and reached close to saturation for plasma acetate concentration > 2-3 mM, whereas brain acetate concentration continued to increase. The Michaelis-Menten constant for brain acetate utilization ( KMutil=0.01±0.14mM) was much smaller than for acetate transport through the blood-brain barrier ( KMt=4.18±0.83mM). The maximum transport capacity of acetate through the blood-brain barrier ( Vmaxt=0.96±0.18μmol/g/min) was nearly two-fold higher than the maximum rate of brain acetate utilization ( Vmaxutil=0.50±0.08μmol/g/min). We conclude that, under our experimental conditions, brain acetate utilization is saturated when plasma acetate concentrations increase above 2-3 mM. At such high plasma acetate concentration, the rate-limiting step for glial acetate metabolism is not the blood-brain barrier, but occurs after entry of acetate into the brain. PMID:19393008

  8. Waxholm Space atlas of the Sprague Dawley rat brain.

    PubMed

    Papp, Eszter A; Leergaard, Trygve B; Calabrese, Evan; Johnson, G Allan; Bjaalie, Jan G

    2014-08-15

    Three-dimensional digital brain atlases represent an important new generation of neuroinformatics tools for understanding complex brain anatomy, assigning location to experimental data, and planning of experiments. We have acquired a microscopic resolution isotropic MRI and DTI atlasing template for the Sprague Dawley rat brain with 39 μm isotropic voxels for the MRI volume and 78 μm isotropic voxels for the DTI. Building on this template, we have delineated 76 major anatomical structures in the brain. Delineation criteria are provided for each structure. We have applied a spatial reference system based on internal brain landmarks according to the Waxholm Space standard, previously developed for the mouse brain, and furthermore connected this spatial reference system to the widely used stereotaxic coordinate system by identifying cranial sutures and related stereotaxic landmarks in the template using contrast given by the active staining technique applied to the tissue. With the release of the present atlasing template and anatomical delineations, we provide a new tool for spatial orientation analysis of neuroanatomical location, and planning and guidance of experimental procedures in the rat brain. The use of Waxholm Space and related infrastructures will connect the atlas to interoperable resources and services for multi-level data integration and analysis across reference spaces. PMID:24726336

  9. EVALUATION OF PERFLUOROOCTANE SULFONATE IN THE RAT BRAIN

    EPA Science Inventory

    Perfluorooctane Sulfonate (PFOS) is an environmentally persistent chemical that has been detected in humans and wildlife. PFOS is primarily distributed in liver and blood. The current study evaluated the level of PFOS in the adult and neonatal rat brain and determined whether t...

  10. Autoradiographic localization of relaxin binding sites in rat brain

    SciTech Connect

    Osheroff, P.L.; Phillips, H.S. )

    1991-08-01

    Relaxin is a member of the insulin family of polypeptide hormones and exerts its best understood actions in the mammalian reproductive system. Using a biologically active 32P-labeled human relaxin, the authors have previously shown by in vitro autoradiography specific relaxin binding sites in rat uterus, cervix, and brain tissues. Using the same approach, they describe here a detailed localization of human relaxin binding sites in the rat brain. Displaceable relaxin binding sites are distributed in discrete regions of the olfactory system, neocortex, hypothalamus, hippocampus, thalamus, amygdala, midbrain, and medulla of the male and female rat brain. Characterization of the relaxin binding sites in the subfornical organ and neocortex reveals a single class of high-affinity sites (Kd = 1.4 nM) in both regions. The binding of relaxin to two of the circumventricular organs (subfornical organ and organum vasculosum of the lamina terminalis) and the neurosecretory magnocellular hypothalamic nuclei (i.e., paraventricular and supraoptic nuclei) provides the anatomical and biochemical basis for emerging physiological evidence suggesting a central role for relaxin in the control of blood pressure and hormone release. They conclude that specific, high-affinity relaxin binding sites are present in discrete regions of the rat brain and that the distribution of some of these sites may be consistent with a role for relaxin in control of vascular volume and blood pressure.

  11. EFFECTS OF CHLORINE DIOXIDE ON THE DEVELOPING RAT BRAIN

    EPA Science Inventory

    Male and female Long-Evans rat pups, exposed to an oral dose of 14 mg chlorine dioxide C102)/kg/d (postnatal d 10), were examined for effects on brain development and for changes in thyroid activity. ody weight reductions were observed on postnatal (pn) d 11, 21, and 35. orebrain...

  12. Thyroid insufficiency in developing rat brain: A genomic analysis.

    EPA Science Inventory

    Thyroid Insufficiency in the Developing Rat Brain: A Genomic Analysis. JE Royland and ME Gilbert, Neurotox. Div., U.S. EPA, RTP, NC, USA. Endocrine disruption (ED) is an area of major concern in environmental neurotoxicity. Severe deficits in thyroid hormone (TH) levels have bee...

  13. Inducible Gene Manipulations in Brain Serotonergic Neurons of Transgenic Rats

    PubMed Central

    Tews, Björn; Bartsch, Dusan

    2011-01-01

    The serotonergic (5-HT) system has been implicated in various physiological processes and neuropsychiatric disorders, but in many aspects its role in normal and pathologic brain function is still unclear. One reason for this might be the lack of appropriate animal models which can address the complexity of physiological and pathophysiological 5-HT functioning. In this respect, rats offer many advantages over mice as they have been the animal of choice for sophisticated neurophysiological and behavioral studies. However, only recently technologies for the targeted and tissue specific modification of rat genes - a prerequisite for a detailed study of the 5-HT system - have been successfully developed. Here, we describe a rat transgenic system for inducible gene manipulations in 5-HT neurons. We generated a Cre driver line consisting of a tamoxifen-inducible CreERT2 recombinase under the control of mouse Tph2 regulatory sequences. Tissue-specific serotonergic Cre recombinase expression was detected in four transgenic TPH2-CreERT2 rat founder lines. For functional analysis of Cre-mediated recombination, we used a rat Cre reporter line (CAG-loxP.EGFP), in which EGFP is expressed after Cre-mediated removal of a loxP-flanked lacZ STOP cassette. We show an in-depth characterisation of this rat Cre reporter line and demonstrate its applicability for monitoring Cre-mediated recombination in all major neuronal subpopulations of the rat brain. Upon tamoxifen induction, double transgenic TPH2-CreERT2/CAG-loxP.EGFP rats show selective and efficient EGFP expression in 5-HT neurons. Without tamoxifen administration, EGFP is only expressed in few 5-HT neurons which confirms minimal background recombination. This 5-HT neuron specific CreERT2 line allows Cre-mediated, inducible gene deletion or gene overexpression in transgenic rats which provides new opportunities to decipher the complex functions of the mammalian serotonergic system. PMID:22140568

  14. Chronic Methamphetamine Effects on Brain Structure and Function in Rats.

    PubMed

    Thanos, Panayotis K; Kim, Ronald; Delis, Foteini; Ananth, Mala; Chachati, George; Rocco, Mark J; Masad, Ihssan; Muniz, Jose A; Grant, Samuel C; Gold, Mark S; Cadet, Jean Lud; Volkow, Nora D

    2016-01-01

    Methamphetamine (MA) addiction is a growing epidemic worldwide. Chronic MA use has been shown to lead to neurotoxicity in rodents and humans. Magnetic resonance imaging (MRI) studies in MA users have shown enlarged striatal volumes and positron emission tomography (PET) studies have shown decreased brain glucose metabolism (BGluM) in the striatum of detoxified MA users. The present study examines structural changes of the brain, observes microglial activation, and assesses changes in brain function, in response to chronic MA treatment. Rats were randomly split into three distinct treatment groups and treated daily for four months, via i.p. injection, with saline (controls), or low dose (LD) MA (4 mg/kg), or high dose (HD) MA (8 mg/kg). Sixteen weeks into the treatment period, rats were injected with a glucose analog, [18F] fluorodeoxyglucose (FDG), and their brains were scanned with micro-PET to assess regional BGluM. At the end of MA treatment, magnetic resonance imaging at 21T was performed on perfused rats to determine regional brain volume and in vitro [3H]PK 11195 autoradiography was performed on fresh-frozen brain tissue to measure microglia activation. When compared with controls, chronic HD MA-treated rats had enlarged striatal volumes and increases in [3H]PK 11195 binding in striatum, the nucleus accumbens, frontal cortical areas, the rhinal cortices, and the cerebellar nuclei. FDG microPET imaging showed that LD MA-treated rats had higher BGluM in insular and somatosensory cortices, face sensory nucleus of the thalamus, and brainstem reticular formation, while HD MA-treated rats had higher BGluM in primary and higher order somatosensory and the retrosplenial cortices, compared with controls. HD and LD MA-treated rats had lower BGluM in the tail of the striatum, rhinal cortex, and subiculum and HD MA also had lower BGluM in hippocampus than controls. These results corroborate clinical findings and help further examine the mechanisms behind MA

  15. Chronic Methamphetamine Effects on Brain Structure and Function in Rats

    PubMed Central

    Thanos, Panayotis K.; Kim, Ronald; Delis, Foteini; Ananth, Mala; Chachati, George; Rocco, Mark J.; Masad, Ihssan; Muniz, Jose A.; Grant, Samuel C.; Gold, Mark S.; Cadet, Jean Lud; Volkow, Nora D.

    2016-01-01

    Methamphetamine (MA) addiction is a growing epidemic worldwide. Chronic MA use has been shown to lead to neurotoxicity in rodents and humans. Magnetic resonance imaging (MRI) studies in MA users have shown enlarged striatal volumes and positron emission tomography (PET) studies have shown decreased brain glucose metabolism (BGluM) in the striatum of detoxified MA users. The present study examines structural changes of the brain, observes microglial activation, and assesses changes in brain function, in response to chronic MA treatment. Rats were randomly split into three distinct treatment groups and treated daily for four months, via i.p. injection, with saline (controls), or low dose (LD) MA (4 mg/kg), or high dose (HD) MA (8 mg/kg). Sixteen weeks into the treatment period, rats were injected with a glucose analog, [18F] fluorodeoxyglucose (FDG), and their brains were scanned with micro-PET to assess regional BGluM. At the end of MA treatment, magnetic resonance imaging at 21T was performed on perfused rats to determine regional brain volume and in vitro [3H]PK 11195 autoradiography was performed on fresh-frozen brain tissue to measure microglia activation. When compared with controls, chronic HD MA-treated rats had enlarged striatal volumes and increases in [3H]PK 11195 binding in striatum, the nucleus accumbens, frontal cortical areas, the rhinal cortices, and the cerebellar nuclei. FDG microPET imaging showed that LD MA-treated rats had higher BGluM in insular and somatosensory cortices, face sensory nucleus of the thalamus, and brainstem reticular formation, while HD MA-treated rats had higher BGluM in primary and higher order somatosensory and the retrosplenial cortices, compared with controls. HD and LD MA-treated rats had lower BGluM in the tail of the striatum, rhinal cortex, and subiculum and HD MA also had lower BGluM in hippocampus than controls. These results corroborate clinical findings and help further examine the mechanisms behind MA

  16. DNA methylation markers in the postnatal developing rat brain

    PubMed Central

    Simmons, Rebecca K.; Stringfellow, Sara A.; Glover, Matthew E.; Wagle, Anjali A.; Clinton, Sarah M.

    2013-01-01

    In spite of intense interest in how altered epigenetic processes including DNA methylation may contribute to psychiatric and neurodevelopmental disorders, there is a limited understanding of how methylation processes change during early postnatal brain development. The present study used in situ hybridization to assess mRNA expression for the three major DNA methyltranserases (DNMTs) – DNMT1, DNMT3a and DNMT3b – in the developing rat brain at seven developmental timepoints: postnatal days (P) 1, 4, 7, 10, 14, 21, and 75. We also assessed 5-methylcytosine levels (an indicator of global DNA methylation) in selected brain regions during the first three postnatal weeks. DNMT1, DNMT3a and DNMT3b mRNAs are widely expressed throughout the adult and postnatal developing rat brain. Overall, DNMT mRNA levels reached their highest point in the first week of life and gradually decreased over the first three postnatal weeks within the hippocampus, amygdala, striatum, cingulate and lateral septum. Global DNA methylation levels did not follow this developmental pattern; methylation levels gradually increased over the first three postnatal weeks in the hippocampus, and remained stable in the developing amygdala and prefrontal cortex. Our results contribute to a growing understanding of how DNA methylation markers unfold in the developing brain, and highlight how these developmental processes may differ within distinct brain regions. PMID:23954679

  17. Developmental Vitamin D3 deficiency alters the adult rat brain.

    PubMed

    Féron, F; Burne, T H J; Brown, J; Smith, E; McGrath, J J; Mackay-Sim, A; Eyles, D W

    2005-03-15

    There is growing evidence that Vitamin D(3) (1,25-dihydroxyvitamin D(3)) is involved in brain development. We have recently shown that the brains of newborn rats from Vitamin D(3) deficient dams were larger than controls, had increased cell proliferation, larger lateral ventricles, and reduced cortical thickness. Brains from these animals also had reduced expression of nerve growth factor (NGF) and glial cell line-derived neurotrophic factor. The aim of the current study was to examine if there were any permanent outcomes into adulthood when the offspring of Vitamin D(3) deficient dams were restored to a normal diet. The brains of adult rats were examined at 10 weeks of age after Vitamin D(3) deficiency until birth or weaning. Compared to controls animals that were exposed to transient early Vitamin D(3) deficiency had larger lateral ventricles, reduced NGF protein content, and reduced expression of a number genes involved in neuronal structure, i.e. neurofilament or MAP-2 or neurotransmission, i.e. GABA-A(alpha4). We conclude that transient early life hypovitaminosis D(3) not only disrupts brain development but leads to persistent changes in the adult brain. In light of the high incidence of hypovitaminosis D(3) in women of child-bearing age, the public health implications of these findings warrant attention. PMID:15763180

  18. Regional Distribution of Copper, Zinc and Iron in Brain of Wistar Rat Model for Non-Wilsonian Brain Copper Toxicosis.

    PubMed

    Pal, Amit; Prasad, Rajendra

    2016-03-01

    In previous studies, we have reported first in vivo evidence of copper deposition in the choroid plexus, cognitive impairments, astrocytes swelling (Alzheimer type II cells) and astrogliosis (increase in number of astrocytes), and degenerated neurons coupled with significant increase in the hippocampus copper and zinc content in copper-intoxicated Wistar rats. Nonetheless, hippocampus iron levels were not affected by chronic copper-intoxication. Notwithstanding information on distribution of copper, zinc and iron status in different regions of brain due to chronic copper exposure remains fragmentary. In continuation with our previous study, the aim of this study was to investigate the effects of intraperitoneally injected copper lactate (0.15 mg Cu/100 g body weight) daily for 90 days on copper, zinc and iron levels in different regions of the brain using atomic absorption spectrophotometry. Copper-intoxicated group showed significantly increased cortex, cerebellum and striatum copper content (76, 46.8 and 80.7 % increase, respectively) compared to control group. However, non-significant changes were observed for the zinc and iron content in cortex, cerebellum and striatum due to chronic copper exposure. In conclusion, the current study demonstrates that chronic copper toxicity causes differential copper buildup in cortex, cerebellum and striatum region of central nervous system of male Wistar rats; signifying the critical requirement to discretely evaluate the effect of copper neurotoxicity in different brain regions, and ensuing neuropathological and cognitive dysfunctions. PMID:26855494

  19. Correlation between subacute sensorimotor deficits and brain water content after surgical brain injury in rats.

    PubMed

    McBride, Devin W; Wang, Yuechun; Sherchan, Prativa; Tang, Jiping; Zhang, John H

    2015-09-01

    Brain edema is a major contributor to poor outcome and reduced quality of life after surgical brain injury (SBI). Although SBI pathophysiology is well-known, the correlation between cerebral edema and neurological deficits has not been thoroughly examined in the rat model of SBI. Thus, the purpose of this study was to determine the correlation between brain edema and deficits in standard sensorimotor neurobehavior tests for rats subjected to SBI. Sixty male Sprague-Dawley rats were subjected to either sham surgery or surgical brain injury via partial frontal lobectomy. All animals were tested for neurological deficits 24 post-SBI and fourteen were also tested 72 h after surgery using seven common behavior tests: modified Garcia neuroscore (Neuroscore), beam walking, corner turn test, forelimb placement test, adhesive removal test, beam balance test, and foot fault test. After assessing the functional outcome, animals were euthanized for brain water content measurement. Surgical brain injury resulted in significantly elevated frontal lobe brain water content 24 and 72 h after surgery compared to that of sham animals. In all behavior tests, significance was observed between sham and SBI animals. However, a correlation between brain water content and functional outcome was observed for all tests except Neuroscore. The selection of behavior tests is critical to determine the effectiveness of therapeutics. Based on this study's results, we recommend using beam walking, the corner turn test, the beam balance test, and the foot fault test since correlations with brain water content were observed at both 24 and 72 h post-SBI. PMID:25975171

  20. Abdominal surgery activates nesfatin-1 immunoreactive brain nuclei in rats.

    PubMed

    Stengel, Andreas; Goebel, Miriam; Wang, Lixin; Taché, Yvette

    2010-02-01

    Abdominal surgery-induced postoperative gastric ileus is well established to induce Fos expression in specific brain nuclei in rats within 2-h after surgery. However, the phenotype of activated neurons has not been thoroughly characterized. Nesfatin-1 was recently discovered in the rat hypothalamus as a new anorexigenic peptide that also inhibits gastric emptying and is widely distributed in rat brain autonomic nuclei suggesting an involvement in stress responses. Therefore, we investigated whether abdominal surgery activates nesfatin-1-immunoreactive (ir) neurons in the rat brain. Two hours after abdominal surgery with cecal palpation under short isoflurane anesthesia or anesthesia alone, rats were transcardially perfused and brains processed for double immunohistochemical labeling of Fos and nesfatin-1. Abdominal surgery, compared to anesthesia alone, induced Fos expression in neurons of the supraoptic nucleus (SON), paraventricular nucleus (PVN), locus coeruleus (LC), Edinger-Westphal nucleus (EW), rostral raphe pallidus (rRPa), nucleus of the solitary tract (NTS) and ventrolateral medulla (VLM). Double Fos/nesfatin-1 labeling showed that of the activated cells, 99% were nesfatin-1-immunoreactive in the SON, 91% in the LC, 82% in the rRPa, 74% in the EW and VLM, 71% in the anterior parvicellular PVN, 47% in the lateral magnocellular PVN, 41% in the medial magnocellular PVN, 14% in the NTS and 9% in the medial parvicellular PVN. These data established nesfatin-1 immunoreactive neurons in specific nuclei of the hypothalamus and brainstem as part of the neuronal response to abdominal surgery and suggest a possible implication of nesfatin-1 in the alterations of food intake and gastric transit associated with such a stressor. PMID:19944727

  1. Human and rat brain lipofuscin proteome

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The accumulation of an autofluorescent pigment called lipofuscin in neurons is an invariable hallmark of brain aging. So far, this material has been considered to be waste material without particular relevance for cellular pathology. However, two lines of evidence argue that lipofuscin may have yet ...

  2. Preserved Modular Network Organization in the Sedated Rat Brain

    PubMed Central

    Bruns, Andreas; Künnecke, Basil; von Kienlin, Markus; Van der Linden, Annemie; Mueggler, Thomas; Verhoye, Marleen

    2014-01-01

    Translation of resting-state functional connectivity (FC) magnetic resonance imaging (rs-fMRI) applications from human to rodents has experienced growing interest, and bears a great potential in pre-clinical imaging as it enables assessing non-invasively the topological organization of complex FC networks (FCNs) in rodent models under normal and various pathophysiological conditions. However, to date, little is known about the organizational architecture of FCNs in rodents in a mentally healthy state, although an understanding of the same is of paramount importance before investigating networks under compromised states. In this study, we characterized the properties of resting-state FCN in an extensive number of Sprague-Dawley rats (n = 40) under medetomidine sedation by evaluating its modular organization and centrality of brain regions and tested for reproducibility. Fully-connected large-scale complex networks of positively and negatively weighted connections were constructed based on Pearson partial correlation analysis between the time courses of 36 brain regions encompassing almost the entire brain. Applying recently proposed complex network analysis measures, we show that the rat FCN exhibits a modular architecture, comprising six modules with a high between subject reproducibility. In addition, we identified network hubs with strong connections to diverse brain regions. Overall our results obtained under a straight medetomidine protocol show for the first time that the community structure of the rat brain is preserved under pharmacologically induced sedation with a network modularity contrasting from the one reported for deep anesthesia but closely resembles the organization described for the rat in conscious state. PMID:25181007

  3. Effect of acute thioacetamide administration on rat brain phospholipid metabolism

    SciTech Connect

    Osada, J.; Aylagas, H.; Miro-Obradors, M.J.; Arce, C.; Palacios-Alaiz, E.; Cascales, M. )

    1990-09-01

    Brain phospholipid composition and the ({sup 32}P)orthophosphate incorporation into brain phospholipids of control and rats treated for 3 days with thioacetamide were studied. Brain phospholipid content, phosphatidylcholine, phosphatidylethanolamine, lysolecithin and phosphatidic acid did not show any significant change by the effect of thioacetamide. In contrast, thioacetamide induced a significant decrease in the levels of phosphatidylserine, sphingomyelin, phosphatidylinositol and diphosphatidylglycerol. After 75 minutes of intraperitoneal label injection, specific radioactivity of all the above phospholipids with the exception of phosphatidylethanolamine and phosphatidylcholine significantly increased. After 13 hours of isotope administration the specific radioactivity of almost all studied phospholipid classes was elevated, except for phosphatidic acid, the specific radioactivity of which did not change and for diphosphatidylglycerol which showed a decrease in specific radioactivity. These results suggest that under thioacetamide treatment brain phospholipids undergo metabolic transformations that may contribute to the hepatic encephalopathy induced by thioacetamide.

  4. Determination of boron distribution in rat's brain, kidney and liver.

    PubMed

    Pazirandeh, Ali; Jameie, Behnam; Zargar, Maysam

    2009-07-01

    To determine relative boron distribution in rat's brain, liver and kidney, a mixture of boric acid and borax, was used. After transcardial injection of the solution, the animals were sacrificed and the brain, kidney and liver were removed. The coronal sections of certain areas of the brain were prepared by freezing microtome. The slices were sandwiched within two pieces of CR-39. The samples were bombarded in a thermal neutron field of the TRR pneumatic facility. The alpha tracks are registered on CR-39 after being etched in NaOH. The boron distribution was determined by counting these alpha tracks CR-39 plastics. The distribution showed non-uniformity in brain, liver and kidney. PMID:19375929

  5. Analysis of pralidoxime in serum, brain and CSF of rats.

    PubMed

    Kalász, Huba; Szöko, Eva; Tábi, Tamás; Petroianu, Georg A; Lorke, Dietrich E; Omar, Abdulrab; Alafifi, Salem; Jasem, Almerri; Tekes, Kornélia

    2009-05-01

    After administration of various amounts of pralidoxime to rats, the levels in serum, brain and cerebrospinal fluid (CSF) were measured using capillary zone electrophoresis (CZE). The calibration curves were established using spiked samples. The calibration covers the ranges from 0.3 - 200 microg/mL, 0.3 - 7 microg/mL and 0.1 - 7 microg/mL for serum, brain and CSF, respectively. The CZE measurement opens the way to the fast and reliable determination of pyridinium aldoxime concentrations in serum, cerebrospinal fluid and brain, thereby monitoring blood-brain and blood-CSF penetration of pyridinium aldoxime-type antidotes clinically used in organophosphate poisoning. PMID:19442213

  6. Effects of Treating Old Rats with an Aqueous Agaricus blazei Extract on Oxidative and Functional Parameters of the Brain Tissue and Brain Mitochondria

    PubMed Central

    de Sá-Nakanishi, Anacharis B.; Soares, Andréia A.; de Oliveira, Andrea Luiza; Fernando Comar, Jurandir; Peralta, Rosane M.; Bracht, Adelar

    2014-01-01

    Dysfunction of the mitochondrial respiratory chain and increased oxidative stress is a striking phenomenon in the brain of aged individuals. For this reason there has been a constant search for drugs and natural products able to prevent or at least to mitigate these problems. In the present study the effects of an aqueous extract of Agaricus blazei, a medicinal mushroom, on the oxidative state and on the functionality of mitochondria from the brain of old rats (21 months) were conducted. The extract was administered intragastrically during 21 days at doses of 200 mg/kg. The administration of the A. blazei extract was protective to the brain of old rats against oxidative stress by decreasing the lipid peroxidation levels and the reactive oxygen species content and by increasing the nonenzymic and enzymic antioxidant capacities. Administration of the A. blazei extract also increased the activity of several mitochondrial respiratory enzymes and, depending on the substrate, the mitochondrial coupled respiration. PMID:24876914

  7. Increase of 5-hydroxytryptamine in the rat brain by raunescine

    PubMed Central

    Paasonen, M. K.; Kärki, N. T.

    1959-01-01

    The Rauwolfia alkaloid raunescine (5 mg./kg., intraperitoneally) increased the concentration of 5-hydroxytryptamine in the brains of rats after iproniazid pre-treatment. This was evident 3 to 4 hr. after raunescine administration. There was no general increase in the noradrenaline content of the brains. In the intestine, raunescine depleted the 5-hydroxytryptamine content by about 50% within 3 to 4 hr. if the animals had been pre-treated with iproniazid. Iproniazid did not increase the content of noradrenaline in the intestine. PMID:13662567

  8. Spectral and lifetime domain measurements of rat brain tumours

    NASA Astrophysics Data System (ADS)

    Abi Haidar, D.; Leh, B.; Allaoua, K.; Genoux, A.; Siebert, R.; Steffenhagen, M.; Peyrot, D.; Sandeau, N.; Vever-Bizet, C.; Bourg-Heckly, G.; Chebbi, I.; Collado-Hilly, M.

    2012-02-01

    During glioblastoma surgery, delineation of the brain tumour margins remains difficult especially since infiltrated and normal tissues have the same visual appearance. This problematic constitutes our research interest. We developed a fibre-optical fluorescence probe for spectroscopic and time domain measurements. First measurements of endogenous tissue fluorescence were performed on fresh and fixed rat tumour brain slices. Spectral characteristics, fluorescence redox ratios and fluorescence lifetime measurements were analysed. Fluorescence information collected from both, lifetime and spectroscopic experiments, appeared promising for tumour tissue discrimination. Two photon measurements were performed on the same fixed tissue. Different wavelengths are used to acquire two-photon excitation-fluorescence of tumorous and healthy sites.

  9. Brain and behavioral perturbations in rats following Western diet access.

    PubMed

    Hargrave, Sara L; Davidson, Terry L; Lee, Tien-Jui; Kinzig, Kimberly P

    2015-10-01

    Energy dense "Western" diets (WD) are known to cause obesity as well as learning and memory impairments, blood-brain barrier damage, and psychological disturbances. Impaired glucose (GLUT1) and monocarboxylate (MCT1) transport may play a role in diet-induced dementia development. In contrast, ketogenic diets (KD) have been shown to be neuroprotective. We assessed the effect of 10, 40 and 90 days WD, KD and Chow maintenance on spontaneous alternation (SA) and vicarious trial and error (VTE) behaviors in male rats, then analyzed blood glucose, insulin, and ketone levels; and hippocampal GLUT1 and MCT1 mRNA. Compared to Chow and KD, rats fed WD had increased 90 day insulin levels. SA was decreased in WD rats at 10, but not 40 or 90 days. VTE was perturbed in WD-fed rats, particularly at 10 and 90 days, indicating hippocampal deficits. WD rats had lower hippocampal GLUT1 and MCT1 expression compared to Chow and KD, and KD rats had increased 90 day MCT1 expression compared to Chow and WD. These data suggest that WD reduces glucose and monocarboxylate transport at the hippocampus, which may result in learning and memory deficits. Further, KD consumption may be useful for MCT1 transporter recovery, which may benefit cognition. PMID:25862980

  10. Feed the brain: insights into the study of neurovascular coupling.

    PubMed

    Welsh, Donald G; Ledoux, Jonathan

    2015-04-01

    The microcirculation is tightly regulated by a diverse range of mechanisms which share the common goal of matching blood flow delivery with tissue metabolic demand. Despite in-depth examination of tissues like skeletal muscle, brain microcirculation has remained largely unexplored due to methodological limitations. Recent, technological advances have, however, started to grant greater access to this vital microcirculatory bed. This overview is part of a Special Topics Issue centered on the methodology, theory, and mechanistic basis of neurovascular coupling. Solicited manuscripts have been purposely written in an opinionated manner to provoke thought and to illuminate new emerging areas of investigation. PMID:25771945

  11. Oxidative changes in brain of aniline-exposed rats

    SciTech Connect

    Kakkar, P.; Awasthi, S.; Viswanathan, P.N. )

    1992-10-01

    Oxidative stress in rat cerebellum, cortex and brain stem after a short-term high-dose exposure to aniline vapors under conditions akin to those after major chemical accidents, was studied. Significant increases in superoxide dismutase isozyme activities and formation of thiobarbituric acid reactive material along with depletion of ascorbic acid and non-protein sulfhydryl content suggest impairment of antioxidant defenses 24 h after single exposure to 15,302 ppm aniline vapors for 10 min.

  12. [Effect of phenibut on interhemispheric transmission in the rat brain].

    PubMed

    Borodkina, L E; Molodavkin, G M; Tiurenkov, I N

    2009-01-01

    Effects of the nootropic drug phenibut on the transcallosal potential amplitude in the sensomotor brain cortex have been studied in rats. It is established that a single administration of phenibut in a dose of 25 mg/kg (i.p.) increases the transcallosal response amplitude, thus improving the interhemispheric transmission. This effect, being an objective evidence of the nootrope activity, confirms the drug status and corroborates the positive action of phenibut on the learning and memory processes. PMID:19334513

  13. Identification of rat brain opioid (enkephalin) receptor by photoaffinity labeling

    SciTech Connect

    Yeung, C.W.

    1986-01-01

    A photoreactive, radioactive enkephalin derivative was prepared and purified by high performance liquid chromatography. Rat brain and spinal cord plasma membranes were incubated with this radioiodinated photoprobe and were subsequently photolysed. Autoradiography of the sodium dodecyl sulfate gel electrophoresis of the solubilized and reduced membranes showed that a protein having an apparent molecular weight of 46,000 daltons was specifically labeled, suggesting that this protein may be the opioid (enkephalin) receptor.

  14. Multiple opiate receptors in the brain of spontaneously hypertensive rats

    SciTech Connect

    Das, S.; Bhargava, H.N.

    1986-03-01

    The characteristics of ..mu.., delta and kappa -opiate receptors in the brain of spontaneously hypertensive (SH) and normotensive Wistar-Kyoto (WKY) rats were determined using the receptor binding assays. The ligands used were /sup 3/H-naltrexone (..mu..), /sup 3/H-ethylketocyclazocine (EKC, kappa) and /sup 3/H-Tyr-D-Ser-Gly-Phe-Leu-Thr (DSTLE, delta). Since EKC binds to ..mu.. and delta receptors in addition to kappa, the binding was done in the presence of 100 nM each of DAGO and DADLE to suppress ..mu.. and delta sites, respectively. All three ligands bound to brain membranes of WKY rats at a single high affinity site with the following B/sub max/ (fmol/mg protein) and K/sub d/ (nM) values: /sup 3/H-naltrexone (130.5; 0.43) /sup 3/H-EKC (19.8, 1.7) and /sup 3/H-DSTLE (139, 2.5). The binding of /sup 3/H-naltrexone and /sup 3/H-DSTLE in the brain of WKY and SH did not differ. A consistent increase (22%) in B/sub max/ of /sup 3/H-EKC was found in SHR compared to WKY rats. However, the K/sub d/ values did not differ. The increase in B/sub max/ was due to increases in hypothalamus and cortex. It is concluded that SH rats have higher density of kappa-opiate receptors, particularly in hypothalamus and cortex, compared to WKY rats, and that kappa-opiate receptors may be involved in the pathophysiology of hypertension.

  15. Gelation and fodrin purification from rat brain extracts.

    PubMed

    Levilliers, N; Péron-Renner, M; Coffe, G; Pudles, J

    1986-06-01

    Extracts from rat brain tissue have been shown to give rise to a gel which exhibits the following features. It is mainly enriched in actin and in a high-molecular-weight protein with polypeptide chains of 235 and 240 kDa, which we identified as fodrin. Tubulin is also a major component of the gel but it appears to be trapped non-specifically during the gelation process. Gelation is pH-, ionic strength- and Ca2+-concentration-dependent, and is optimal under the conditions which promote the interaction between polymerized actin and fodrin. In a similar way to that described for the purification of rat brain actin (Levilliers, N., Péron-Renner, M., Coffe, G. and Pudles, J. (1984) Biochimie 66, 531-537), we used the gelation system as a selective means of recovering fodrin from the mixture of a low-ionic-strength extract from whole rat brain and a high-ionic-strength extract of the particulate fraction. From this gel, fodrin was purified with a good yield by a simple procedure involving gel dissociation in 0.5 M KCl and depolymerization in 0.7 M KI, Bio-Gel A-15m chromatography, followed by ammonium sulfate precipitation. PMID:3707993

  16. Ketone-body utilization by homogenates of adult rat brain

    SciTech Connect

    Lopes-Cardozo, M.; Klein, W.

    1982-06-01

    The regulation of ketone-body metabolism and the quantitative importance of ketone bodies as lipid precursors in adult rat brain has been studied in vitro. Utilization of ketone bodies and of pyruvate by homogenates of adult rat brain was measured and the distribution of /sup 14/C from (3-/sup 14/C)ketone bodies among the metabolic products was analysed. The rate of ketone-body utilization was maximal in the presence of added Krebs-cycle intermediates and uncouplers of oxidative phosphorylation. The consumption of acetoacetate was faster than that of D-3-hydroxybutyrate, whereas, pyruvate produced twice as much acetyl-CoA as acetoacetate under optimal conditions. Millimolar concentrations of ATP in the presence of uncoupler lowered the consumption of ketone bodies but not of pyruvate. Indirect evidence is presented suggesting that ATP interferes specifically with the mitochondrial uptake of ketone bodies. Interconversion of ketone bodies and the accumulation of acid-soluble intermediates (mainly citrate and glutamate) accounted for the major part of ketone-body utilization, whereas only a small part was oxidized to CO/sub 2/. Ketone bodies were not incorporated into lipids or protein. We conclude that adult rat-brain homogenates use ketone bodies exclusively for oxidative purposes.

  17. Cerebral circulation, metabolism, and blood-brain barrier of rats in hypocapnic hypoxia

    SciTech Connect

    Beck, T.; Krieglstein, J.

    1987-03-01

    The effects of hypoxic hypoxia on physiological variables, cerebral circulation, cerebral metabolism, and blood-brain barrier were investigated in conscious, spontaneously breathing rats by exposing them to an atmosphere containing 7% O/sub 2/. Hypoxia affected a marked hypotension, hypocapnia and alkalosis. Cortical tissue high-energy phosphates and glucose content were not affected by hypoxia, glucose 6-phosphate lactate, and pyruvate levels were significantly increased. Blood-brain barrier permeability, regional brain glucose content and lumped constant were not changed by hypoxia. Local cerebral glucose utilization (LCGU) rose by 40-70% of control values in gray matter and by 80-90% in white matter. Under hypoxia, columns of increased and decreased LCGU and were detectable in cortical gray matter. Color-coded (/sup 14/C)2-deoxy-D-glucose autoradiograms of rat brain are shown. Local cerebral blood flow (LCBF) increased by 50-90% in gray matter and by up to 180% in white matter. Coupling between LCGU and LCBF in hypoxia remained unchanged. The data suggests a stimulation of glycolysis, increased glucose transport into the cell, and increased hexokinase activity. The physiological response of gray and white matter to hypoxia obviously differs. Uncoupling of the relation between LCGU and LCBF does not occur.

  18. Astaxanthin reduces ischemic brain injury in adult rats

    PubMed Central

    Shen, Hui; Kuo, Chi-Chung; Chou, Jenny; Delvolve, Alice; Jackson, Shelley N.; Post, Jeremy; Woods, Amina S.; Hoffer, Barry J.; Wang, Yun; Harvey, Brandon K.

    2009-01-01

    Astaxanthin (ATX) is a dietary carotenoid of crustaceans and fish that contributes to their coloration. Dietary ATX is important for development and survival of salmonids and crustaceans and has been shown to reduce cardiac ischemic injury in rodents. The purpose of this study was to examine whether ATX can protect against ischemic injury in the mammalian brain. Adult rats were injected intracerebroventricularly with ATX or vehicle prior to a 60-min middle cerebral artery occlusion (MCAo). ATX was present in the infarction area at 70-75 min after onset of MCAo. Treatment with ATX, compared to vehicle, increased locomotor activity in stroke rats and reduced cerebral infarction at 2 d after MCAo. To evaluate the protective mechanisms of ATX against stroke, brain tissues were assayed for free radical damage, apoptosis, and excitoxicity. ATX antagonized ischemia-mediated loss of aconitase activity and reduced glutamate release, lipid peroxidation, translocation of cytochrome c, and TUNEL labeling in the ischemic cortex. ATX did not alter physiological parameters, such as body temperature, brain temperature, cerebral blood flow, blood gases, blood pressure, and pH. Collectively, our data suggest that ATX can reduce ischemia-related injury in brain tissue through the inhibition of oxidative stress, reduction of glutamate release, and antiapoptosis. ATX may be clinically useful for patients vulnerable or prone to ischemic events.—Shen, H., Kuo, C.-C., Chou, J., Delvolve, A., Jackson, S. N., Post, J., Woods, A. S., Hoffer, B. J., Wang, Y., Harvey, B. K. Astaxanthin reduces ischemic brain injury in adult rats. PMID:19218497

  19. The First in Vivo Observation of 13C- 15N Coupling in Mammalian Brain

    NASA Astrophysics Data System (ADS)

    Kanamori, Keiko; Ross, Brian D.

    2001-12-01

    [5-13C,15N]Glutamine, with 1J(13C-15N) of 16 Hz, was observed in vivo in the brain of spontaneously breathing rats by 13C MRS at 4.7 T. The brain [5-13C]glutamine peak consisted of the doublet from [5-13C,15N]glutamine and the center [5-13C,14N]glutamine peak, resulting in an apparent triplet with a separation of 8 Hz. The time course of formation of brain [5-13C,15N]glutamine was monitored in vivo with a time resolution of 20-35 min. This [5-13C,15N]glutamine was formed by glial uptake of released neurotransmitter [5-13C]glutamate and its reaction with 15NH3 catalyzed by the glia-specific glutamine synthetase. The neurotransmitter glutamate C5 was selectively13C-enriched by intravenous [2,5-13C]glucose infusion to 13C-label whole-brain glutamate C5, followed by [12C]glucose infusion to chase 13C from the small and rapidly turning-over glial glutamate pool, leaving 13C mainly in the neurotransmitter [5-13C]glutamate pool, which is sequestered in vesicles until release. Hence, the observed [5-13C,15N]glutamine arises from a coupling between 13C of neuronal origin and 15N of glial origin. Measurement of the rate of brain [5-13C,15N]glutamine formation provides a novel noninvasive method of studying the kinetics of neurotransmitter uptake into glia in vivo, a process that is crucial for protecting the brain from glutamate excitotoxicity.

  20. Outer brain barriers in rat and human development

    PubMed Central

    Brøchner, Christian B.; Holst, Camilla B.; Møllgård, Kjeld

    2015-01-01

    Complex barriers at the brain's surface, particularly in development, are poorly defined. In the adult, arachnoid blood-cerebrospinal fluid (CSF) barrier separates the fenestrated dural vessels from the CSF by means of a cell layer joined by tight junctions. Outer CSF-brain barrier provides diffusion restriction between brain and subarachnoid CSF through an initial radial glial end feet layer covered with a pial surface layer. To further characterize these interfaces we examined embryonic rat brains from E10 to P0 and forebrains from human embryos and fetuses (6–21st weeks post-conception) and adults using immunohistochemistry and confocal microscopy. Antibodies against claudin-11, BLBP, collagen 1, SSEA-4, MAP2, YKL-40, and its receptor IL-13Rα2 and EAAT1 were used to describe morphological characteristics and functional aspects of the outer brain barriers. Claudin-11 was a reliable marker of the arachnoid blood-CSF barrier. Collagen 1 delineated the subarachnoid space and stained pial surface layer. BLBP defined radial glial end feet layer and SSEA-4 and YKL-40 were present in both leptomeningeal cells and end feet layer, which transformed into glial limitans. IL-13Rα2 and EAAT1 were present in the end feet layer illustrating transporter/receptor presence in the outer CSF-brain barrier. MAP2 immunostaining in adult brain outlined the lower border of glia limitans; remnants of end feet were YKL-40 positive in some areas. We propose that outer brain barriers are composed of at least 3 interfaces: blood-CSF barrier across arachnoid barrier cell layer, blood-CSF barrier across pial microvessels, and outer CSF-brain barrier comprising glial end feet layer/pial surface layer. PMID:25852456

  1. Magnetic micelles for DNA delivery to rat brains after mild traumatic brain injury.

    PubMed

    Das, Mahasweta; Wang, Chunyan; Bedi, Raminder; Mohapatra, Shyam S; Mohapatra, Subhra

    2014-10-01

    Traumatic brain injury (TBI) causes significant mortality, long term disability and psychological symptoms. Gene therapy is a promising approach for treatment of different pathological conditions. Here we tested chitosan and polyethyleneimine (PEI)-coated magnetic micelles (CP-mag micelles or CPMMs), a potential MRI contrast agent, to deliver a reporter DNA to the brain after mild TBI (mTBI). CPMM-tomato plasmid (ptd) conjugate expressing a red-fluorescent protein (RFP) was administered intranasally immediately after mTBI or sham surgery in male SD rats. Evans blue extravasation following mTBI suggested CPMM-ptd entry into the brain via the compromised blood-brain barrier. Magnetofection increased the concentration of CPMMs in the brain. RFP expression was observed in the brain (cortex and hippocampus), lung and liver 48 h after mTBI. CPMM did not evoke any inflammatory response by themselves and were excreted from the body. These results indicate the possibility of using intranasally administered CPMM as a theranostic vehicle for mTBI. From the clinical editor: In this study, chitosan and PEI-coated magnetic micelles (CPMM) were demonstrated as potentially useful vehicles in traumatic brain injury in a rodent model. Magnetofection increased the concentration of CPMMs in the brain and, after intranasal delivery, CPMM did not evoke any inflammatory response and were excreted from the body. PMID:24486465

  2. Deferoxamine attenuates acute hydrocephalus after traumatic brain injury in rats

    PubMed Central

    Zhao, Jinbing; Chen, Zhi; Xi, Guohua; Keep, Richard F.; Hua, Ya

    2014-01-01

    Acute post-traumatic ventricular dilation and hydrocephalus are relatively frequent consequences of traumatic brain injury (TBI). Several recent studies have indicated that high iron level in brain may relate to hydrocephalus development after intracranial hemorrhage. However, the role of iron in the development of post-traumatic hydrocephalus is still unclear. This study was to determine whether or not iron has a role in hydrocephalus development after TBI. TBI was induced by lateral fluid-percussion in male Sprague-Dawley rats. Some rats had intraventricular injection of iron. Acute hydrocephalus was measured by magnetic resonance T2-weighted imaging and brain hemorrhage was determined by T2* gradient-echo sequence imaging and brain hemoglobin levels. The effect of deferoxamine on TBI-induced hydrocephalus was examined. TBI resulted in acute hydrocephalus at 24 hours (lateral ventricle volume: 24.1±3.0 vs. 9.9±0.2 mm3 in sham group). Intraventricular injection of iron also caused hydrocephalus (25.7 ± 3.4 vs. 9.0 ± 0.6 mm3 in saline group). Deferoxamine treatment attenuated TBI-induced hydrocephalus and heme oxygenase-1 upregulation. In conclusion, iron may contribute to acute hydrocephalus after TBI. PMID:24935175

  3. Astaxanthin reduces ischemic brain injury in adult rats.

    PubMed

    Shen, Hui; Kuo, Chi-Chung; Chou, Jenny; Delvolve, Alice; Jackson, Shelley N; Post, Jeremy; Woods, Amina S; Hoffer, Barry J; Wang, Yun; Harvey, Brandon K

    2009-06-01

    Astaxanthin (ATX) is a dietary carotenoid of crustaceans and fish that contributes to their coloration. Dietary ATX is important for development and survival of salmonids and crustaceans and has been shown to reduce cardiac ischemic injury in rodents. The purpose of this study was to examine whether ATX can protect against ischemic injury in the mammalian brain. Adult rats were injected intracerebroventricularly with ATX or vehicle prior to a 60-min middle cerebral artery occlusion (MCAo). ATX was present in the infarction area at 70-75 min after onset of MCAo. Treatment with ATX, compared to vehicle, increased locomotor activity in stroke rats and reduced cerebral infarction at 2 d after MCAo. To evaluate the protective mechanisms of ATX against stroke, brain tissues were assayed for free radical damage, apoptosis, and excitoxicity. ATX antagonized ischemia-mediated loss of aconitase activity and reduced glutamate release, lipid peroxidation, translocation of cytochrome c, and TUNEL labeling in the ischemic cortex. ATX did not alter physiological parameters, such as body temperature, brain temperature, cerebral blood flow, blood gases, blood pressure, and pH. Collectively, our data suggest that ATX can reduce ischemia-related injury in brain tissue through the inhibition of oxidative stress, reduction of glutamate release, and antiapoptosis. ATX may be clinically useful for patients vulnerable or prone to ischemic events. PMID:19218497

  4. Photoacoustic imaging for transvascular drug delivery to the rat brain

    NASA Astrophysics Data System (ADS)

    Watanabe, Ryota; Sato, Shunichi; Tsunoi, Yasuyuki; Kawauchi, Satoko; Takemura, Toshiya; Terakawa, Mitsuhiro

    2015-03-01

    Transvascular drug delivery to the brain is difficult due to the blood-brain barrier (BBB). Thus, various methods for safely opening the BBB have been investigated, for which real-time imaging methods are desired both for the blood vessels and distribution of a drug. Photoacoustic (PA) imaging, which enables depth-resolved visualization of chromophores in tissue, would be useful for this purpose. In this study, we performed in vivo PA imaging of the blood vessels and distribution of a drug in the rat brain by using an originally developed compact PA imaging system with fiber-based illumination. As a test drug, Evans blue (EB) was injected to the tail vein, and a photomechanical wave was applied to the targeted brain tissue to increase the permeability of the blood vessel walls. For PA imaging of blood vessels and EB distribution, nanosecond pulses at 532 nm and 670 nm were used, respectively. We clearly visualized blood vessels with diameters larger than 50 μm and the distribution of EB in the brain, showing spatiotemporal characteristics of EB that was transvascularly delivered to the target tissue in the brain.

  5. Detecting Behavioral Deficits Post Traumatic Brain Injury in Rats.

    PubMed

    Awwad, Hibah O

    2016-01-01

    Traumatic brain injury (TBI), ranging from mild to severe, almost always elicits an array of behavioral deficits in injured subjects. Some of these TBI-induced behavioral deficits include cognitive and vestibulomotor deficits as well as anxiety and other consequences. Rodent models of TBI have been (and still are) fundamental in establishing many of the pathophysiological mechanisms of TBI. Animal models are also utilized in screening and testing pharmacological effects of potential therapeutic agents for brain injury treatment. This chapter details validated protocols for each of these behavioral deficits post traumatic brain injury in Sprague-Dawley male rats. The elevated plus maze (EPM) protocol is described for assessing anxiety-like behavior; the Morris water maze protocol for assessing cognitive deficits in learning memory and spatial working memory and the rotarod test for assessing vestibulomotor deficits. PMID:27604739

  6. Global Proteomic Analysis of Brain Tissues in Transient Ischemia Brain Damage in Rats

    PubMed Central

    Chen, Jiann-Hwa; Kuo, Hsing-Chun; Lee, Kam-Fai; Tsai, Tung-Hu

    2015-01-01

    Ischemia-reperfusion injury resulting from arterial occlusion or hypotension in patients leads to tissue hypoxia with glucose deprivation, which causes endoplasmic reticulum (ER) stress and neuronal death. A proteomic approach was used to identify the differentially expressed proteins in the brain of rats following a global ischemic stroke. The mechanisms involved the action in apoptotic and ER stress pathways. Rats were treated with ischemia-reperfusion brain injuries by the bilateral occlusion of the common carotid artery. The cortical neuron proteins from the stroke animal model (SAM) and the control rats were separated using two-dimensional gel electrophoresis (2-DE) to purify and identify the protein profiles. Our results demonstrated that the SAM rats experienced brain cell death in the ischemic core. Fifteen proteins were expressed differentially between the SAM rats and control rats, which were assayed and validated in vivo and in vitro. Interestingly, the set of differentially expressed, down-regulated proteins included catechol O-methyltransferase (COMT) and cathepsin D (CATD), which are implicated in oxidative stress, inflammatory response and apoptosis. After an ischemic stroke, one protein spot, namely the calretinin (CALB2) protein, showed increased expression. It mediated the effects of SAM administration on the apoptotic and ER stress pathways. Our results demonstrate that the ischemic injury of neuronal cells increased cell cytoxicity and apoptosis, which were accompanied by sustained activation of the IRE1-alpha/TRAF2, JNK1/2, and p38 MAPK pathways. Proteomic analysis suggested that the differential expression of CALB2 during a global ischemic stroke could be involved in the mechanisms of ER stress-induced neuronal cell apoptosis, which occurred via IRE1-alpha/TRAF2 complex formation, with activation of JNK1/2 and p38 MAPK. Based on these results, we also provide the molecular evidence supporting the ischemia-reperfusion-related neuronal injury

  7. Coupled water transport by rat proximal tubule.

    PubMed

    Green, R; Giebisch, G; Unwin, R; Weinstein, A M

    1991-12-01

    Simultaneous microperfusion of proximal tubules and peritubular capillaries in kidneys of rats anesthetized with Inactin was used to examine water reabsorption by this epithelium. Osmolality of the luminal solution was varied with changes in NaCl concentration and by the addition of raffinose. Capillary perfusates contained either low (2 g/dl) or high (16 g/dl) concentrations of albumin. We used low-bicarbonate perfusates for both lumen and capillary so that we might apply the nonequilibrium thermodynamic model of transport for a single solute (NaCl) to interpret our observations. Linear regression with the volume flux equation Jv = -Lp delta II - Lp sigma delta C + Jav (where Jv is volume flux, Lp is hydraulic conductance, delta II is oncotic force, sigma is osmotic reflection coefficient, delta C is salt concentration difference, and Jav is the component of Jv not attributed to transepithelial hydrostatic or osmotic forces) revealed a tubule water permeability (Pf = 0.11 +/- 0.01 cm/s) and a sigma (0.74 +/- 0.08) in agreement with previous determinations. These transport parameters were unaffected by changes in peritubular protein. We also found that Jav was substantial, approximately three-fourths of the rate of isotonic transport under these perfusion conditions. Further, this component of water transport nearly doubled with the transition from low- to high-protein peritubular capillary perfusion. When expressed as a capacity for water reabsorption against an osmotic gradient, the salt concentration differences required to null volume flux were 13.2 +/- 2.4 and 29.4 +/- 4.0 mosmol/kgH2O under low and high peritubular protein. Our data suggest that this protein effect is, most likely, an increase in solute transport by the tubule epithelial cells. PMID:1750518

  8. Dietary aspartame with protein on plasma and brain amino acids, brain monoamines and behavior in rats.

    PubMed

    Torii, K; Mimura, T; Takasaki, Y; Ichimura, M

    1986-01-01

    Aspartame (APM; L-aspartyl-L-phenylalanine methyl ester), was investigated for its ability to alter levels of the large neutral amino acids and monoamines in overnight fasted rats allowed to consume meals with or without protein for two hours. Additionally, the possible long term behavioral consequences of APM in 25% casein diets with or without 10% sucrose were determined. Acute APM ingestion increased both plasma and brain phenylalanine and tyrosine levels, but brain tryptophan levels were not altered regardless of dietary protein. Brain norepinephrine and dopamine levels were unaltered by any of the diet while serotonin levels were slightly increased when a protein-free diet was consumed. But APM and/or protein ingestion minimized this increase of brain serotonin levels as much as controls. Chronic APM ingestion failed to influence diurnal feeding patterns, meal size distributions, or diurnal patterns of spontaneous motor activity. The chronic ingestion of abuse doses of APM produced no significant chemical changes in brain capable of altering behavioral parameters believed to be controlled by monoamines in rats. PMID:3714850

  9. Light-sheet microscopy imaging of a whole cleared rat brain with Thy1-GFP transgene

    PubMed Central

    Stefaniuk, Marzena; Gualda, Emilio J.; Pawlowska, Monika; Legutko, Diana; Matryba, Paweł; Koza, Paulina; Konopka, Witold; Owczarek, Dorota; Wawrzyniak, Marcin; Loza-Alvarez, Pablo; Kaczmarek, Leszek

    2016-01-01

    Whole-brain imaging with light-sheet fluorescence microscopy and optically cleared tissue is a new, rapidly developing research field. Whereas successful attempts to clear and image mouse brain have been reported, a similar result for rats has proven difficult to achieve. Herein, we report on creating novel transgenic rat harboring fluorescent reporter GFP under control of neuronal gene promoter. We then present data on clearing the rat brain, showing that FluoClearBABB was found superior over passive CLARITY and CUBIC methods. Finally, we demonstrate efficient imaging of the rat brain using light-sheet fluorescence microscopy. PMID:27312902

  10. Light-sheet microscopy imaging of a whole cleared rat brain with Thy1-GFP transgene.

    PubMed

    Stefaniuk, Marzena; Gualda, Emilio J; Pawlowska, Monika; Legutko, Diana; Matryba, Paweł; Koza, Paulina; Konopka, Witold; Owczarek, Dorota; Wawrzyniak, Marcin; Loza-Alvarez, Pablo; Kaczmarek, Leszek

    2016-01-01

    Whole-brain imaging with light-sheet fluorescence microscopy and optically cleared tissue is a new, rapidly developing research field. Whereas successful attempts to clear and image mouse brain have been reported, a similar result for rats has proven difficult to achieve. Herein, we report on creating novel transgenic rat harboring fluorescent reporter GFP under control of neuronal gene promoter. We then present data on clearing the rat brain, showing that FluoClearBABB was found superior over passive CLARITY and CUBIC methods. Finally, we demonstrate efficient imaging of the rat brain using light-sheet fluorescence microscopy. PMID:27312902

  11. Expression cloning of a rat brain somatostatin receptor cDNA.

    PubMed Central

    Kluxen, F W; Bruns, C; Lübbert, H

    1992-01-01

    We have used an expression-cloning strategy to isolate a cDNA encoding a somatostatin (somatotropin release-inhibiting factor, SRIF) receptor from rat cortex and hippocampus. A positive clone was identified by autoradiography after binding of radiolabeled SRIF to COS-1 cells previously transfected with pools of cDNA clones. The deduced amino acid sequence of the receptor displays sequence and structural homology to the family of G-protein-coupled receptors. The affinity of various SRIF analogs to the expressed receptor resembles their effects on growth hormone release from pituitary cells. In addition, the distribution of the mRNA in various tissues corresponds to that described for native SRIF receptors. Therefore, we conclude that we have isolated a rat brain SRIF receptor cDNA. Images PMID:1374909

  12. Autoradiographic localization of angiotensin II receptors in rat brain

    SciTech Connect

    Mendelsohn, F.A.O.; Quirion, R.; Saavedra, J.M.; Aguilera, G.; Catt, K.J.

    1984-03-01

    The /sup 125/I-labeled agonist analog (1-sarcosine)-angiotensin II ((Sar/sup 1/)AII) bound with high specificity and affinity (K/sub a/ = 2 x 10/sup 9/ M/sup -1/) to a single class of receptor sites in rat brain. This ligand was used to analyze the distribution of AII receptors in rat brain by in vitro autoradiography followed by computerized densitometry and color coding. A very high density of AII receptors was found in the subfornical organ, paraventricular and periventricular nuclei of the hypothalamus, nucleus of the tractus solitarius, and area postrema. A high concentration of receptors was found in the suprachiasmatic nucleus of the hypothalamus, lateral olfactory tracts, nuclei of the accessory and lateral olfactory tracts, triangular septal nucleus, subthalamic nucleus, locus coeruleus, and inferior olivary nuclei. Moderate receptor concentrations were found in the organum vasculosum of the lamina terminalis, median preoptic nucleus, medial habenular nucleus, lateral septum, ventroposterior thalamic nucleus, median eminence, medial geniculate nucleus, superior colliculus, subiculum, pre- and parasubiculum, and spinal trigeminal tract. Low concentrations of sites were seen in caudate-putamen, nucleus accumbens, amygdala, and gray matter of the spinal cord. These studies have demonstrated that AII receptors are distributed in a highly characteristic anatomical pattern in the brain. The high concentrations of AII receptors at numerous physiologically relevant sites are consistent with the emerging evidence for multiple roles of AII as a neuropeptide in the central nervous system. 75 references, 2 figures.

  13. Autoradiographic localization of angiotensin II receptors in rat brain.

    PubMed Central

    Mendelsohn, F A; Quirion, R; Saavedra, J M; Aguilera, G; Catt, K J

    1984-01-01

    The 125I-labeled agonist analog [1-sarcosine]-angiotensin II ( [Sar1]AII) bound with high specificity and affinity (Ka = 2 X 10(9) M-1) to a single class of receptor sites in rat brain. This ligand was used to analyze the distribution of AII receptors in rat brain by in vitro autoradiography followed by computerized densitometry and color coding. A very high density of AII receptors was found in the subfornical organ, paraventricular and periventricular nuclei of the hypothalamus, nucleus of the tractus solitarius, and area postrema. A high concentration of receptors was found in the suprachiasmatic nucleus of the hypothalamus, lateral olfactory tracts, nuclei of the accessory and lateral olfactory tracts, triangular septal nucleus, subthalamic nucleus, locus coeruleus, and inferior olivary nuclei. Moderate receptor concentrations were found in the organum vasculosum of the lamina terminalis, median preoptic nucleus, medial habenular nucleus, lateral septum, ventroposterior thalamic nucleus, median eminence, medial geniculate nucleus, superior colliculus, subiculum, pre- and parasubiculum, and spinal trigeminal tract. Low concentrations of sites were seen in caudate-putamen, nucleus accumbens, amygdala, and gray matter of the spinal cord. These studies have demonstrated that AII receptors are distributed in a highly characteristic anatomical pattern in the brain. The high concentrations of AII receptors at numerous physiologically relevant sites are consistent with the emerging evidence for multiple roles of AII as a neuropeptide in the central nervous system. Images PMID:6324205

  14. Localization of histidine decarboxylase mRNA in rat brain.

    PubMed

    Bayliss, D A; Wang, Y M; Zahnow, C A; Joseph, D R; Millhorn, D E

    1990-08-01

    The recent cloning of a cDNA encoding fetal rat liver histidine decarboxylase (HDC), the synthesizing enzyme for histamine, allows the study of the central histaminergic system at the molecular level. To this end, Northern blot and in situ hybridization analyses were used to determine the regional and cellular distribution of neurons which express HDC mRNA in rat brain. Three hybridizing species which migrate as 1.6-, 2.6-, and 3.5-kb RNA were identified with Northern blots. The major (2.6 kb) and minor (3.5 kb) species, characteristic of HDC mRNA in fetal liver, were expressed at high levels in diencephalon and at just detectable levels in hippocampus, but not in other brain regions. In contrast, the 1.6-kb species was present in all brain regions examined except the olfactory bulb. Cells which contain HDC mRNA were found by in situ hybridization in the hypothalamus; HDC mRNA-containing cells were not detected in other areas, including the hippocampus. Hypothalamic neurons which express HDC mRNA were localized to all aspects of the tuberomammillary nucleus, a result consistent with previous immunohistochemical findings. PMID:19912749

  15. Diffuse light reflectance signals as potential indicators of loss of viability in brain tissue due to hypoxia: charge-coupled-device-based imaging and fiber-based measurement

    NASA Astrophysics Data System (ADS)

    Kawauchi, Satoko; Nishidate, Izumi; Uozumi, Yoichi; Nawashiro, Hiroshi; Ashida, Hiroshi; Sato, Shunichi

    2013-01-01

    Brain tissue is highly vulnerable to ischemia/hypoxia, and real-time monitoring of its viability is important. By fiber-based measurements for rat brain, we previously observed a unique triphasic reflectance change (TRC) after a certain period of time after hypoxia. After TRC, rats could not be rescued, suggesting that TRC can be used as an indicator of loss of brain tissue viability. In this study, we investigated this diffuse-reflectance change due to hypoxia in three parts. First, we developed and validated a theoretical method to quantify changes in the absorption and reduced scattering coefficients involved in TRC. Second, we performed charge-coupled-device-based reflectance imaging of the rat brain during hypoxia followed by reoxygenation to examine spatiotemporal characteristics of the reflectance and its correlation with reversibility of brain tissue damage. Third, we made simultaneous imaging and fiber-based measurement of the reflectance for the rat to compare signals obtained by these two modalities. We observed a nontriphasic reflectance change by the imaging, and it was associated with brain tissue viability. We found that TRC measured by the fibers preceded the reflectance-signal change captured by the imaging. This time difference is attributable to the different observation depths in the brain with these two methods.

  16. Diffuse light reflectance signals as potential indicators of loss of viability in brain tissue due to hypoxia: charge-coupled-device-based imaging and fiber-based measurement.

    PubMed

    Kawauchi, Satoko; Nishidate, Izumi; Uozumi, Yoichi; Nawashiro, Hiroshi; Ashida, Hiroshi; Sato, Shunichi

    2013-01-01

    Brain tissue is highly vulnerable to ischemia/hypoxia, and real-time monitoring of its viability is important. By fiber-based measurements for rat brain, we previously observed a unique triphasic reflectance change (TRC) after a certain period of time after hypoxia. After TRC, rats could not be rescued, suggesting that TRC can be used as an indicator of loss of brain tissue viability. In this study, we investigated this diffuse-reflectance change due to hypoxia in three parts. First, we developed and validated a theoretical method to quantify changes in the absorption and reduced scattering coefficients involved in TRC. Second, we performed charge-coupled-device-based reflectance imaging of the rat brain during hypoxia followed by reoxygenation to examine spatiotemporal characteristics of the reflectance and its correlation with reversibility of brain tissue damage. Third, we made simultaneous imaging and fiber-based measurement of the reflectance for the rat to compare signals obtained by these two modalities. We observed a nontriphasic reflectance change by the imaging, and it was associated with brain tissue viability. We found that TRC measured by the fibers preceded the reflectance-signal change captured by the imaging. This time difference is attributable to the different observation depths in the brain with these two methods. PMID:23291715

  17. Biotelemetric Monitoring of Brain Neurochemistry in Conscious Rats Using Microsensors and Biosensors

    PubMed Central

    Calia, Giammario; Rocchitta, Gaia; Migheli, Rossana; Puggioni, Giulia; Spissu, Ylenia; Bazzu, Gianfranco; Mazzarello, Vittorio; Lowry, John P.; O’Neill, Robert D.; Desole, Maria S.; Serra, Pier A.

    2009-01-01

    In this study we present the real-time monitoring of three key brain neurochemical species in conscious rats using implantable amperometric electrodes interfaced to a biotelemetric device. The new system, derived from a previous design, was coupled with carbon-based microsensors and a platinum-based biosensor for the detection of ascorbic acid (AA), O2 and glucose in the striatum of untethered, freely-moving rats. The miniaturized device consisted of a single-supply sensor driver, a current-to-voltage converter, a microcontroller and a miniaturized data transmitter. The redox currents were digitized to digital values by means of an analog-to-digital converter integrated in a peripheral interface controller (PIC), and sent to a personal computer by means of a miniaturized AM transmitter. The electronics were calibrated and tested in vitro under different experimental conditions and exhibited high stability, low power consumption and good linear response in the nanoampere current range. The in-vivo results confirmed previously published observations on striatal AA, oxygen and glucose dynamics recorded in tethered rats. This approach, based on simple and inexpensive components, could be used as a rapid and reliable model for studying the effects of different drugs on brain neurochemical systems. PMID:22574029

  18. Changes in Brain Metallome/Metabolome Pattern due to a Single i.v. Injection of Manganese in Rats

    PubMed Central

    Neth, Katharina; Lucio, Marianna; Walker, Alesia; Zorn, Julia; Schmitt-Kopplin, Philippe; Michalke, Bernhard

    2015-01-01

    Exposure to high concentrations of Manganese (Mn) is known to potentially induce an accumulation in the brain, leading to a Parkinson related disease, called manganism. Versatile mechanisms of Mn-induced brain injury are discussed, with inactivation of mitochondrial defense against oxidative stress being a major one. So far, studies indicate that the main Mn-species entering the brain are low molecular mass (LMM) compounds such as Mn-citrate. Applying a single low dose MnCl2 injection in rats, we observed alterations in Mn-species pattern within the brain by analysis of aqueous brain extracts by size-exclusion chromatography—inductively coupled plasma mass spectrometry (SEC-ICP-MS). Additionally, electrospray ionization—ion cyclotron resonance-Fourier transform-mass spectrometry (ESI-ICR/FT-MS) measurement of methanolic brain extracts revealed a comprehensive analysis of changes in brain metabolisms after the single MnCl2 injection. Major alterations were observed for amino acid, fatty acid, glutathione, glucose and purine/pyrimidine metabolism. The power of this metabolomic approach is the broad and detailed overview of affected brain metabolisms. We also correlated results from the metallomic investigations (Mn concentrations and Mn-species in brain) with the findings from metabolomics. This strategy might help to unravel the role of different Mn-species during Mn-induced alterations in brain metabolism. PMID:26383269

  19. A simple implantation method for flexible, multisite microelectrodes into rat brains

    PubMed Central

    Richter, Anja; Xie, Yijing; Schumacher, Anett; Löffler, Susanne; Kirch, Robert D.; Al-Hasani, Jaafar; Rapoport, Daniel H.; Kruse, Charli; Moser, Andreas; Tronnier, Volker; Danner, Sandra; Hofmann, Ulrich G.

    2013-01-01

    A long term functional and reliable coupling between neural tissue and implanted microelectrodes is the key issue in acquiring neural electrophysiological signals or therapeutically excite neural tissue. The currently often used rigid micro-electrodes are thought to cause a severe foreign body reaction resulting in a thick glial scar and consequently a poor tissue-electrode coupling in the chronic phase. We hypothesize, that this adverse effect might be remedied by probes compliant to the soft brain tissue, i.e., replacing rigid electrodes by flexible ones. Unfortunately, this flexibility comes at the price of a low stiffness, which makes targeted low trauma implantation very challenging. In this study, we demonstrate an adaptable and simple method to implant extremely flexible microprobes even to deep areas of rat's brain. Implantation of flexible probes is achieved by rod supported stereotactic insertion fostered by a hydrogel (2% agarose in PBS) cushion on the exposed skull. We were thus able to implant very flexible micro-probes in 70 rats as deep as the rodent's subthalamic nucleus. This work describes in detail the procedures and steps needed for minimal invasive, but reliable implantation of flexible probes. PMID:23898266

  20. Measurement and pharmacokinetics of vincamine in rat blood and brain using microdialysis.

    PubMed

    Juan, Ying-Ping; Tsai, Tung-Hu

    2005-09-23

    Vincamine is an alkaloid compound derived from the Vinca minor plant. Since little is known concerning its pharmacokinetics and appropriate analytical method, this study focuses on its pharmacokinetics as well the possible roles of the multidrug transporter P-glycoprotein on its distribution and disposition. We develop a rapid and sensitive method using a microdialysis coupled with liquid chromatography for the concurrent determination of unbound vincamine in rat blood and brain. Microdialysis probes were simultaneously inserted into the jugular vein toward heart and brain hippocampus of male Sprague-Dawley rats for sampling in biological fluids following the administration of vincamine (10 and 30 mg/kg) through the femoral vein. Samples were eluted with a mobile phase containing methanol-1% diethylamine (pH 7.15) in water (75:25, v/v) and the flow rate of the mobile phase was 0.7 ml/min. Pharmacokinetic parameters of vincamine were derived using compartmental model. The decline of protein-unbound vincamine in the hippocampus and blood suggested that there was rapid exchange and equilibration between the peripheral compartment and the central nervous system. In the presence of cyclosporine, unbound vincamine levels in both blood and brain were significantly increased. PMID:16130744

  1. The blood-brain barrier penetration and distribution of PEGylated fluorescein-doped magnetic silica nanoparticles in rat brain

    SciTech Connect

    Ku, Shuting; Yan, Feng; Wang, Ying; Sun, Yilin; Yang, Nan; Ye, Ling

    2010-04-16

    PEGylated PAMAM conjugated fluorescein-doped magnetic silica nanoparticles (PEGylated PFMSNs) have been synthesized for evaluating their ability across the blood-brain barrier (BBB) and distribution in rat brain. The obtained nanoparticles were characterized by transmission electron microscopy (TEM), thermal gravimetry analyses (TGA), zeta potential ({zeta}-potential) titration, and X-ray photoelectron spectroscopy (XPS). The BBB penetration and distribution of PEGylated PFMSNs and FMSNs in rat brain were investigated not only at the cellular level with Confocal laser scanning microscopy (CLSM), but also at the subcellular level with transmission electron microscopy (TEM). The results provide direct evidents that PEGylated PFMSNs could penetrate the BBB and spread into the brain parenchyma.

  2. Intranasal pyrrolidine dithiocarbamate decreases brain inflammatory mediators and provides neuroprotection after brain hypoxia-ischemia in neonatal rats

    PubMed Central

    Wang, Zhi; Zhao, Huijuan; Peng, Shuling; Zuo, Zhiyi

    2013-01-01

    Brain injury due to birth asphyxia is the major cause of death and long-term disabilities in newborns. We determined whether intranasal pyrrolidine dithiocarbamate (PDTC) could provide neuroprotection in neonatal rats after brain hypoxia-ischemia (HI). Seven-day old male and female Sprague-Dawley rats were subjected to brain HI. They were then treated by intranasal PDTC. Neurological outcome were evaluated 7 or 30 days after the brain HI. Brain tissues were harvested 6 or 24 h after the brain HI for biochemical analysis. Here, PDTC dose-dependently reduced brain HI-induced brain tissue loss with an effective dose (ED)50 at 27 mg/kg. PDTC needed to be applied within 45 min after the brain HI for this neuroprotection. This treatment reduced brain tissue loss and improved neurological and cognitive functions assessed 30 days after the HI. PDTC attenuated brain HI-induced lipid oxidative stress, nuclear translocation of nuclear factor κ-light-chain-enhancer of activated B cells, and various inflammatory mediators in the brain tissues. Inhibition of inducible nitric oxide synthase after brain HI reduced brain tissue loss. Our results suggest that intranasal PDTC provides neuroprotection possibly via reducing inflammation and oxidative stress. Intranasal PDTC may have a potential to provide neuroprotection to human neonates after birth asphyxia. PMID:23994718

  3. Investigations on iodothyronine deiodinase activity in the maturing rat brain.

    PubMed

    Ködding, R; Fuhrmann, H; von zur Mühlen, A

    1986-04-01

    5-Monodeiodination of T4 and T3 and 5'-monodeiodination of T4 and rT3 were studied in brain homogenates of male Sprague-Dawley rats, aged 1-60 days. Portions of the homogenates were incubated with the substrates at 37 C for 30 min. The reaction products were estimated by specific RIAs. All of the four reactions were dependent upon time, temperature, pH, and upon the concentrations of substrate, thiol, and tissue protein. Maximal reactions were obtained between 40 and 160 mM dithioerythritol. T4 5'-deiodination proceeded optimally at pH 7.4 and 0.4 microM substrate, the other reactions at pH 8.5 and 10 microM substrate. The four reactions were inactivated by heat (56 C, 30 min) and inhibited by 10(-5) M iopanoic acid. Only rT3 5'-deiodination was inhibited by 3 X 10(-4) M propylthiouracil (greater than 95%). In cerebellum, basal ganglia, brainstem, and hypothalamus both T4 and T3 5-deiodinase activity were very high in perinatal rats [up to 5.56 pmol/(min X mg protein) in hypothalamus], and decreased rapidly with age. In cortex and olfactory bulb these enzyme activities were low after birth, followed by an increase during the growth spurt [up to 632 fmol/(min X mg protein) in olfactory bulb]. T4 and rT3 5'-deiodinase activity in all brain regions studied were at their lowest in perinatal rats. During and after the growth spurt an increase was observed [up to 457 fmol/(min X mg protein) in cerebellum]. The reciprocal course of 5- and 5'-deiodination between birth and growth spurt in most of the brain regions studied might lead to a reduced intracellular thyromimetic activity during the perinatal period. PMID:3948784

  4. Brain tumor imaging of rat fresh tissue using terahertz spectroscopy

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Sayuri; Fukushi, Yasuko; Kubota, Oichi; Itsuji, Takeaki; Ouchi, Toshihiko; Yamamoto, Seiji

    2016-07-01

    Tumor imaging by terahertz spectroscopy of fresh tissue without dye is demonstrated using samples from a rat glioma model. The complex refractive index spectrum obtained by a reflection terahertz time-domain spectroscopy system can discriminate between normal and tumor tissues. Both the refractive index and absorption coefficient of tumor tissues are higher than those of normal tissues and can be attributed to the higher cell density and water content of the tumor region. The results of this study indicate that terahertz technology is useful for detecting brain tumor tissue.

  5. Brain tumor imaging of rat fresh tissue using terahertz spectroscopy

    PubMed Central

    Yamaguchi, Sayuri; Fukushi, Yasuko; Kubota, Oichi; Itsuji, Takeaki; Ouchi, Toshihiko; Yamamoto, Seiji

    2016-01-01

    Tumor imaging by terahertz spectroscopy of fresh tissue without dye is demonstrated using samples from a rat glioma model. The complex refractive index spectrum obtained by a reflection terahertz time-domain spectroscopy system can discriminate between normal and tumor tissues. Both the refractive index and absorption coefficient of tumor tissues are higher than those of normal tissues and can be attributed to the higher cell density and water content of the tumor region. The results of this study indicate that terahertz technology is useful for detecting brain tumor tissue. PMID:27456312

  6. 2-hydroxyestradiol modifies serotonergic processes in the male rat brain

    SciTech Connect

    Kowalik, S.

    1985-01-01

    The effects of chronic (5 day) 2-hydroxyestradiol or estradiol on catecholaminergic and serotonergic neurons in the male rat brain were studied. The results indicate estrogen to be specific is inducing changes in dopaminergic systems; whereas its hydroxymetabolite appears to have a preference for serotonergic processes. In particular, in vitro 2-hydroxyestradiol appears to be a potent inhibitor of /sup 3/H-imipramine binding in brain; this inhibition is especially potent in the cortex, where it is equal in potency to serotonin. However, unlike serotonin, which is a competitive inhibitor of imipramine, 2-hydroxyestradiol is an uncompetitive inhibitor of /sup 3/H-imipramine binding in cortex and hypothalamus and a noncompetitive inhibitor in the striatum; this suggests that the inhibition of binding takes place at a point other than the site of serotonin uptake. In vitro 2-hydroxyestradiol also appears to increase the uptake of serotonin into these tissues, a change which would be expected if the imipramine binding is blocked.

  7. The impact of chronic stress on the rat brain lipidome.

    PubMed

    Oliveira, T G; Chan, R B; Bravo, F V; Miranda, A; Silva, R R; Zhou, B; Marques, F; Pinto, V; Cerqueira, J J; Di Paolo, G; Sousa, N

    2016-01-01

    Chronic stress is a major risk factor for several human disorders that affect modern societies. The brain is a key target of chronic stress. In fact, there is growing evidence indicating that exposure to stress affects learning and memory, decision making and emotional responses, and may even predispose for pathological processes, such as Alzheimer's disease and depression. Lipids are a major constituent of the brain and specifically signaling lipids have been shown to regulate brain function. Here, we used a mass spectrometry-based lipidomic approach to evaluate the impact of a chronic unpredictable stress (CUS) paradigm on the rat brain in a region-specific manner. We found that the prefrontal cortex (PFC) was the area with the highest degree of changes induced by chronic stress. Although the hippocampus presented relevant lipidomic changes, the amygdala and, to a greater extent, the cerebellum presented few lipid changes upon chronic stress exposure. The sphingolipid and phospholipid metabolism were profoundly affected, showing an increase in ceramide (Cer) and a decrease in sphingomyelin (SM) and dihydrosphingomyelin (dhSM) levels, and a decrease in phosphatidylethanolamine (PE) and ether phosphatidylcholine (PCe) and increase in lysophosphatidylethanolamine (LPE) levels, respectively. Furthermore, the fatty-acyl profile of phospholipids and diacylglycerol revealed that chronic stressed rats had higher 38 carbon(38C)-lipid levels in the hippocampus and reduced 36C-lipid levels in the PFC. Finally, lysophosphatidylcholine (LPC) levels in the PFC were found to be correlated with blood corticosterone (CORT) levels. In summary, lipidomic profiling of the effect of chronic stress allowed the identification of dysregulated lipid pathways, revealing putative targets for pharmacological intervention that may potentially be used to modulate stress-induced deficits. PMID:25754084

  8. Data for mitochondrial proteomic alterations in the developing rat brain.

    PubMed

    Villeneuve, Lance M; Stauch, Kelly L; Fox, Howard S

    2014-12-01

    Mitochondria are a critical organelle involved in many cellular processes, and due to the nature of the brain, neuronal cells are almost completely reliant on these organelles for energy generation. Due to the fact that biomedical research tends to investigate disease state pathogenesis, one area of mitochondrial research commonly overlooked is homeostatic responses to energy demands. Therefore, to elucidate mitochondrial alterations occurring during the developmentally important phase of E18 to P7 in the brain, we quantified the proteins in the mitochondrial proteome as well as proteins interacting with the mitochondria. We identified a large number of significantly altered proteins involved in a variety of pathways including glycolysis, mitochondrial trafficking, mitophagy, and the unfolded protein response. These results are important because we identified alterations thought to be homeostatic in nature occurring within mitochondria, and these results may be used to identify any abnormal deviations in the mitochondrial proteome occurring during this period of brain development. A more comprehensive analysis of this data may be obtained from the article "Proteomic analysis of mitochondria from embryonic and postnatal rat brains reveals response to developmental changes in energy demands" in the Journal of Proteomics. PMID:26217684

  9. Repetitive Transcranial Magnetic Stimulation Activates Specific Regions in Rat Brain

    NASA Astrophysics Data System (ADS)

    Ji, Ru-Rong; Schlaepfer, Thomas E.; Aizenman, Carlos D.; Epstein, Charles M.; Qiu, Dike; Huang, Justin C.; Rupp, Fabio

    1998-12-01

    Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive technique to induce electric currents in the brain. Although rTMS is being evaluated as a possible alternative to electroconvulsive therapy for the treatment of refractory depression, little is known about the pattern of activation induced in the brain by rTMS. We have compared immediate early gene expression in rat brain after rTMS and electroconvulsive stimulation, a well-established animal model for electroconvulsive therapy. Our result shows that rTMS applied in conditions effective in animal models of depression induces different patterns of immediate-early gene expression than does electroconvulsive stimulation. In particular, rTMS evokes strong neural responses in the paraventricular nucleus of the thalamus (PVT) and in other regions involved in the regulation of circadian rhythms. The response in PVT is independent of the orientation of the stimulation probe relative to the head. Part of this response is likely because of direct activation, as repetitive magnetic stimulation also activates PVT neurons in brain slices.

  10. Gene Transfer into Rat Brain Using Adenoviral Vectors

    PubMed Central

    Puntel, Mariana; Kroeger, Kurt M.; Sanderson, Nicholas S.R.; Thomas, Clare E.; Castro, Maria G.; Lowenstein, Pedro R.

    2010-01-01

    Viral vector–mediated gene delivery is an attractive procedure for introducing genes into the brain, both for purposes of basic neuroscience research and to develop gene therapy for neurological diseases. Replication-defective adenoviruses possess many features which make them ideal vectors for this purpose—efficiently transducing terminally differentiated cells such as neurons and glial cells, resulting in high levels of transgene expression in vivo. Also, in the absence of anti-adenovirus immunity, these vectors can sustain very long-term transgene expression within the brain parenchyma. This unit provides protocols for the stereotactic injection of adenoviral vectors into the brain, followed by protocols to detect transgene expression or infiltrates of immune cells by immunocytochemistry or immunofluorescence. ELISPOT and neutralizing antibody assay methodologies are provided to quantitate the levels of cellular and humoral immune responses against adenoviruses. Quantitation of adenoviral vector genomes within the rat brain using qPCR is also described. Curr. Protoc. Neurosci. 50:4.24.1–4.24.49. © 2010 by John Wiley & Sons, Inc. PMID:20066657

  11. Data for mitochondrial proteomic alterations in the developing rat brain

    PubMed Central

    Villeneuve, Lance M.; Stauch, Kelly L.; Fox, Howard S.

    2014-01-01

    Mitochondria are a critical organelle involved in many cellular processes, and due to the nature of the brain, neuronal cells are almost completely reliant on these organelles for energy generation. Due to the fact that biomedical research tends to investigate disease state pathogenesis, one area of mitochondrial research commonly overlooked is homeostatic responses to energy demands. Therefore, to elucidate mitochondrial alterations occurring during the developmentally important phase of E18 to P7 in the brain, we quantified the proteins in the mitochondrial proteome as well as proteins interacting with the mitochondria. We identified a large number of significantly altered proteins involved in a variety of pathways including glycolysis, mitochondrial trafficking, mitophagy, and the unfolded protein response. These results are important because we identified alterations thought to be homeostatic in nature occurring within mitochondria, and these results may be used to identify any abnormal deviations in the mitochondrial proteome occurring during this period of brain development. A more comprehensive analysis of this data may be obtained from the article “Proteomic analysis of mitochondria from embryonic and postnatal rat brains reveals response to developmental changes in energy demands” in the Journal of Proteomics. PMID:26217684

  12. Correlation between light scattering signal and tissue reversibility in rat brain exposed to hypoxia

    NASA Astrophysics Data System (ADS)

    Kawauchi, Satoko; Sato, Shunichi; Uozumi, Yoichi; Nawashiro, Hiroshi; Ishihara, Miya; Kikuchi, Makoto

    2010-02-01

    Light scattering signal is a potential indicator of tissue viability in brain because cellular and subcellular structural integrity should be associated with cell viability in brain tissue. We previously performed multiwavelength diffuse reflectance measurement for a rat global ischemic brain model and observed a unique triphasic change in light scattering at a certain time after oxygen and glucose deprivation. This triphasic scattering change (TSC) was shown to precede cerebral ATP exhaustion, suggesting that loss of brain tissue viability can be predicted by detecting scattering signal. In the present study, we examined correlation between light scattering signal and tissue reversibility in rat brain in vivo. We performed transcranial diffuse reflectance measurement for rat brain; under spontaneous respiration, hypoxia was induced for the rat by nitrogen gas inhalation and reoxygenation was started at various time points. We observed a TSC, which started at 140 +/- 15 s after starting nitrogen gas inhalation (mean +/- SD, n=8). When reoxygenation was started before the TSC, all rats survived (n=7), while no rats survived when reoxygenation was started after the TSC (n=8). When reoxygenation was started during the TSC, rats survived probabilistically (n=31). Disability of motor function was not observed for the survived rats. These results indicate that TSC can be used as an indicator of loss of tissue reversibility in brains, providing useful information on the critical time zone for treatment to rescue the brain.

  13. BRAIN TEMPERATURE MEASUREMENT IN RATS: A COMPARISON OF MICROWAVE AND AMBIENT TEMPERATURE EXPOSURES

    EPA Science Inventory

    The brain and core temperatures of rats and rat carcasses exposed to microwave radiation (2450 MHz) or elevated air temperatures were measured in two studies. In general, no substantial evidence for temperature differentials, or hot spots, in the brain of these animals was found....

  14. Hypobaric Hypoxia Imbalances Mitochondrial Dynamics in Rat Brain Hippocampus

    PubMed Central

    Jain, Khushbu; Prasad, Dipti; Singh, Shashi Bala; Kohli, Ekta

    2015-01-01

    Brain is predominantly susceptible to oxidative stress and mitochondrial dysfunction during hypobaric hypoxia, and therefore undergoes neurodegeneration due to energy crisis. Evidences illustrate a high degree of association for mitochondrial fusion/fission imbalance and mitochondrial dysfunction. Mitochondrial fusion/fission is a recently reported dynamic mechanism which frequently occurs among cellular mitochondrial network. Hence, the study investigated the temporal alteration and involvement of abnormal mitochondrial dynamics (fusion/fission) along with disturbed mitochondrial functionality during chronic exposure to hypobaric hypoxia (HH). The Sprague-Dawley rats were exposed to simulated high altitude equivalent to 25000 ft for 3, 7, 14, 21, and 28 days. Mitochondrial morphology, distribution within neurons, enzyme activity of respiratory complexes, Δψm, ADP: ATP, and expression of fission/fusion key proteins were determined. Results demonstrated HH induced alteration in mitochondrial morphology by damaged, small mitochondria observed in neurons with disturbance of mitochondrial functionality and reduced mitochondrial density in neuronal processes manifested by excessive mitochondrial fragmentation (fission) and decreased mitochondrial fusion as compared to unexposed rat brain hippocampus. The study suggested that imbalance in mitochondrial dynamics is one of the noteworthy mechanisms occurring in hippocampal neurons during HH insult. PMID:26236504

  15. Anticonvulsant and neuroprotective effects of Pimpinella anisum in rat brain

    PubMed Central

    2012-01-01

    Background Essential oil of Pimpinella anisum L. Apiaceae (anise oil) has been widely used in traditional Persian medicine to treat a variety of diseases, including some neurological disorders. This study was aimed to test the possible anti-seizure and anti-hypoxia effects of anise oil. Methods The effects of different concentrations of anise oil were tested on seizure attacks induced by pentylenetetrazol (PTZ) injection and neuronal hypoxia induced by oxygen withdrawal as well as on production of dark neurons and induction of long-term potentiation (LTP) in in vivo and in vitro experimental models of rat brain. Results Anise oil significantly prolonged the latency of seizure attacks and reduced the amplitude and duration of epileptiform burst discharges induced by injection of intraperitoneal PTZ. In addition, anise oil significantly inhibited production of dark neurons in different regions of the brain in epileptic rats. Anise oil also significantly enhanced the duration of the appearance of anoxic terminal negativity induced by oxygen withdrawal and inhibited induction of LTP in hippocampal slices. Conclusions Our data indicate the anticonvulsant and neuroprotective effects of anise oil, likely via inhibition of synaptic plasticity. Further evaluation of anise oil to use in the treatment of neurological disorders is suggested. PMID:22709243

  16. Wearable scanning photoacoustic brain imaging in behaving rats.

    PubMed

    Tang, Jianbo; Dai, Xianjin; Jiang, Huabei

    2016-06-01

    A wearable scanning photoacoustic imaging (wPAI) system is presented for noninvasive brain study in behaving rats. This miniaturized wPAI system consists of four pico linear servos and a single transducer-based PAI probe. It has a dimension of 50 mm × 35 mm × 40 mm, and a weight of 26 g excluding cablings. Phantom evaluation shows that wPAI achieves a lateral resolution of ∼0.5 mm and an axial resolution of ∼0.1 mm at a depth of up to 11 mm. Its imaging ability is also tested in a behaving rat, and the results indicate that wPAI is able to image blood vessels at a depth of up to 5 mm with intact scalp and skull. With its noninvasive, deep penetration, and functional imaging ability in behaving animals, wPAI can be used for behavior, cognition, and preclinical brain disease studies. PMID:26777064

  17. Donepezil markedly potentiates memantine neurotoxicity in the adult rat brain.

    PubMed

    Creeley, Catherine E; Wozniak, David F; Nardi, Anthony; Farber, Nuri B; Olney, John W

    2008-02-01

    The NMDA antagonist, memantine (Namenda), and the cholinesterase inhibitor, donepezil (Aricept), are currently being used widely, either individually or in combination, for treatment of Alzheimer's disease (AD). NMDA antagonists have both neuroprotective and neurotoxic properties; the latter is augmented by drugs, such as pilocarpine, that increase cholinergic activity. Whether donepezil, by increasing cholinergic activity, might augment memantine's neurotoxic potential has not been investigated. In the present study, we determined that a dose of memantine (20mg/kg, i.p.), considered to be in the therapeutic (neuroprotective) range for rats, causes a mild neurotoxic reaction in the adult rat brain. Co-administration of memantine (20 or 30 mg/kg) with donepezil (2.5-10mg/kg) markedly potentiated this neurotoxic reaction, causing neuronal injury at lower doses of memantine, and causing the toxic reaction to become disseminated and lethal to neurons throughout many brain regions. These findings raise questions about using this drug combination in AD, especially in the absence of evidence that the combination is beneficial, or that either drug arrests or reverses the disease process. PMID:17112636

  18. Distribution of beacon immunoreactivity in the rat brain.

    PubMed

    Wang, Fei; Tian, De-Run; Tian, Nan; Chen, Hui; Shi, Yu-Shun; Chang, Jaw-Kang; Yang, Jun; Yuan, Lan; Han, Ji-Sheng

    2006-01-01

    Beacon is a novel peptide isolated from the hypothalamus of Israeli sand rat. In the present study, we determined the distribution of beacon in the rat brain using immunohistochemical approach with a polyclonal antiserum directed against the synthetic C-terminal peptide fragment (47-73). The hypothalamus represented the major site of beacon-immunoreactive (IR) cell bodies that were concentrated in the paraventricular nucleus (PVN) and the supraoptic nucleus (SON). Additional immunostained cells were found in the septum, bed nucleus of the stria terminalis, subfornical organ and subcommissural organ. Beacon-IR fibers were seen with high density in the internal layer of the median eminence and low to moderate density in the external layer. Significant beacon-IR fibers were also seen in the nucleus of the solitary tract and lateral reticular formation. The beacon neurons found in the PVN were further characterized by double label immunohistochemistry. Several beacon-IR neurons that resided in the medial PVN were shown to coexpress corticotrophin-releasing hormone (CRH) and most labeled beacon fibers in the external layer of median eminence coexist with CRH. The topographical distribution of beacon-IR in the brain suggests multiple biological activities for beacon in addition to its proposed roles in modulating feeding behaviors and pituitary hormone release. PMID:16157417

  19. Structure, function, and expression pattern of a novel sodium-coupled citrate transporter (NaCT) cloned from mammalian brain.

    PubMed

    Inoue, Katsuhisa; Zhuang, Lina; Maddox, Dennis M; Smith, Sylvia B; Ganapathy, Vadivel

    2002-10-18

    Citrate plays a pivotal role not only in the generation of metabolic energy but also in the synthesis of fatty acids, isoprenoids, and cholesterol in mammalian cells. Plasma levels of citrate are the highest ( approximately 135 microm) among the intermediates of the tricarboxylic acid cycle. Here we report on the cloning and functional characterization of a plasma membrane transporter (NaCT for Na+ -coupled citrate transporter) from rat brain that mediates uphill cellular uptake of citrate coupled to an electrochemical Na+ gradient. NaCT consists of 572 amino acids and exhibits structural similarity to the members of the Na+-dicarboxylate cotransporter/Na+ -sulfate cotransporter (NaDC/NaSi) gene family including the recently identified Drosophila Indy. In rat, the expression of NaCT is restricted to liver, testis, and brain. When expressed heterologously in mammalian cells, rat NaCT mediates the transport of citrate with high affinity (Michaelis-Menten constant, approximately 20 microm) and with a Na+:citrate stoichiometry of 4:1. The transporter does interact with other dicarboxylates and tricarboxylates but with considerably lower affinity. In mouse brain, the expression of NaCT mRNA is evident in the cerebral cortex, cerebellum, hippocampus, and olfactory bulb. NaCT represents the first transporter to be identified in mammalian cells that shows preference for citrate over dicarboxylates. This transporter is likely to play an important role in the cellular utilization of citrate in blood for the synthesis of fatty acids and cholesterol (liver) and for the generation of energy (liver and brain). NaCT thus constitutes a potential therapeutic target for the control of body weight, cholesterol levels, and energy homeostasis. PMID:12177002

  20. Imaging separation of neuronal from vascular effects of cocaine on rat cortical brain in vivo

    SciTech Connect

    Yuan, Z.; Du, C.; Yuan, Z.; Luo, Z.; Volkow, N.D.; Pan, Y.; Du, C.

    2010-09-08

    MRI techniques to study brain function assume coupling between neuronal activity, metabolism and flow. However, recent evidence of physiological uncoupling between neuronal and cerebrovascular events highlights the need for methods to simultaneously measure these three properties. We report a multimodality optical approach that integrates dual-wavelength laser speckle imaging (measures changes in blood flow, blood volume and hemoglobin oxygenation), digital-frequency-ramping optical coherence tomography (images quantitative 3D vascular network) and Rhod2 fluorescence (images intracellular calcium for measure of neuronal activity) at high spatiotemporal resolutions (30 {micro}m, 10 Hz) and over a large field of view (3 x 5 mm{sup 2}). We apply it to assess cocaine's effects in rat cortical brain and show an immediate decrease 3.5 {+-} 0.9 min, phase (1) in the oxygen content of hemoglobin and the cerebral blood flow followed by an overshoot 7.1 {+-} 0.2 min, phase (2) lasting over 20 min whereas Ca{sup 2+} increased immediately (peaked at t = 4.1 {+-} 0.4 min) and remained elevated. This enabled us to identify a delay (2.9 {+-} 0.5 min) between peak neuronal and vascular responses in phase 2. The ability of this multimodality optical approach for simultaneous imaging at high spatiotemporal resolutions permits us to distinguish the vascular versus cellular changes of the brain, thus complimenting other neuroimaging modalities for brain functional studies (e. g., PET, fMRI).

  1. Functional MRI during Hippocampal Deep Brain Stimulation in the Healthy Rat Brain

    PubMed Central

    Van Den Berge, Nathalie; Vanhove, Christian; Descamps, Benedicte; Dauwe, Ine; van Mierlo, Pieter; Vonck, Kristl; Keereman, Vincent; Raedt, Robrecht; Boon, Paul; Van Holen, Roel

    2015-01-01

    Deep Brain Stimulation (DBS) is a promising treatment for neurological and psychiatric disorders. The mechanism of action and the effects of electrical fields administered to the brain by means of an electrode remain to be elucidated. The effects of DBS have been investigated primarily by electrophysiological and neurochemical studies, which lack the ability to investigate DBS-related responses on a whole-brain scale. Visualization of whole-brain effects of DBS requires functional imaging techniques such as functional Magnetic Resonance Imaging (fMRI), which reflects changes in blood oxygen level dependent (BOLD) responses throughout the entire brain volume. In order to visualize BOLD responses induced by DBS, we have developed an MRI-compatible electrode and an acquisition protocol to perform DBS during BOLD fMRI. In this study, we investigate whether DBS during fMRI is valuable to study local and whole-brain effects of hippocampal DBS and to investigate the changes induced by different stimulation intensities. Seven rats were stereotactically implanted with a custom-made MRI-compatible DBS-electrode in the right hippocampus. High frequency Poisson distributed stimulation was applied using a block-design paradigm. Data were processed by means of Independent Component Analysis. Clusters were considered significant when p-values were <0.05 after correction for multiple comparisons. Our data indicate that real-time hippocampal DBS evokes a bilateral BOLD response in hippocampal and other mesolimbic structures, depending on the applied stimulation intensity. We conclude that simultaneous DBS and fMRI can be used to detect local and whole-brain responses to circuit activation with different stimulation intensities, making this technique potentially powerful for exploration of cerebral changes in response to DBS for both preclinical and clinical DBS. PMID:26193653

  2. Lipid peroxidative stress and antioxidative enzymes in brains of milk-supplemented rats.

    PubMed

    Bay, B H; Lee, Y K; Tan, B K; Ling, E A

    1999-12-24

    Skim milk cultured with lactic acid bacteria has been previously reported to reduce lipid peroxidation in rat livers. In this study, the effects of skim milk and cultured milk supplementation on peroxidative stress in brains of weanling rats were investigated. We observed a reduction of brain thiobarbituric acid reacting substances (TBARS) concentration in milk-supplemented animals as compared with controls. In brains of control rats, the superoxide dismutase (SOD) enzyme levels were significantly higher than those from the milk-supplemented animals. In addition, SOD activity in control animal brains had a positive correlation with the TBARS concentration. There was no significant differences in the brain glutathione-S-transferase (GST) levels of all the three groups of animals. The results suggest that milk supplementation may be beneficial in reducing peroxidative stress in the developing rat brain. PMID:10624826

  3. Exercise induces mitochondrial biogenesis after brain ischemia in rats.

    PubMed

    Zhang, Q; Wu, Y; Zhang, P; Sha, H; Jia, J; Hu, Y; Zhu, J

    2012-03-15

    Stroke is a major cause of death worldwide. Previous studies have suggested both exercise and mitochondrial biogenesis contribute to improved post-ischemic recovery of brain function. However, the exact mechanism underlying this effect is unclear. On the other hand, the benefit of exercise-induced mitochondrial biogenesis in brain has been confirmed. In this study, we attempted to determine whether treadmill exercise induces functional improvement through regulation of mitochondrial biogenesis after brain ischemia. We subjected adult male rats to ischemia, followed by either treadmill exercise or non-exercise and analyzed the effect of exercise on the amount of mitochondrial DNA (mtDNA), expression of mitochondrial biogenesis factors, and mitochondrial protein. In the ischemia-exercise group, only peroxisome proliferator activated receptor coactivator-1 (PGC-1) expression was increased significantly after 3 days of treadmill training. However, after 7 days of training, the levels of mtDNA, nuclear respiratory factor 1, NRF-1, mitochondrial transcription factor A, TFAM, and the mitochondrial protein cytochrome C oxidase subunit IV (COXIV) and heat shock protein-60 (HSP60) also increased above levels observed in non-exercised ischemic animals. These changes followed with significant changes in behavioral scores and cerebral infarct volume. The results indicate that exercise can promote mitochondrial biogenesis after ischemic injury, which may serve as a novel component of exercise-induced repair mechanisms of the brain. Understanding the molecular basis for exercise-induced neuroprotection may be beneficial in the development of therapeutic approaches for brain recovery from the ischemic injury. Based upon our findings, stimulation or enhancement of mitochondrial biogenesis may prove a novel neuroprotective strategy in the future. PMID:22266265

  4. Expression of UGT1A subfamily in rat brain.

    PubMed

    Sakakibara, Yukiko; Katoh, Miki; Imai, Kuniyuki; Kondo, Yuya; Asai, Yuki; Ikushiro, Shin-Ichi; Nadai, Masayuki

    2016-07-01

    UDP-glucuronosyltransferase (UGT) is an enzyme that catalyses a major phase II reaction in drug metabolism. Glucuronidation occurs mainly in the liver, but UGTs are also expressed in extrahepatic tissues, where they play an important role in local metabolism. UGT1A isoforms catalyse the glucuronidation of several drugs, neurotransmitters and neurosteroids that exert pharmacological and physiological effects on the brain. The aim of the current study was to determine UGT1A mRNA expression levels and glucuronidation activities in different regions of the rat brain (namely the cerebellum, frontal cortex, parietal cortex, piriform cortex, hippocampus, medulla oblongata, olfactory bulb, striatum and thalamus). It was found that all UGT1A isoforms were expressed in all the nine regions, but their expression levels differed between the regions. The difference between the regions of the brain where the mRNA levels were highest and those where they were lowest ranged between 2.1- to 7.8-fold. Glucuronidation activities were measured using the UGT substrates such as mycophenolic acid, p-nitrophenol and umbelliferone. Glucuronidation activity was detected in all nine regions of the brain. Activity levels differed between the regions, and were highest in the cerebellum, medulla oblongata and olfactory bulb. Differences in glucuronidation activity between regions with the highest rates and those with the lowest rates ranged from 5.3- to 10.1-fold. These results will contribute to our current understanding of the physiological and pharmacokinetic roles of drug-metabolizing enzymes in the brain. Copyright © 2016 John Wiley & Sons, Ltd. PMID:27061716

  5. [Effects of total saponins of semen ziziphi Spinosae on brain damages and brain biochemical parameters under cerebral ischemia of rats].

    PubMed

    Bai, X; Huang, Z; Mo, Z; Pan, H; Ding, H

    1996-02-01

    Total saponins of Semen Ziziphi Spinosae (ZS) can reduce the contents of water and MDA in ischemic rat's brain tissues, elevate the activity of SOD, CK and LDH, cut down the content of lactate and alleviate the damages of nerve cells in brain. The study shows that ZS possesses protective effects on cerebral ischemic injuries. PMID:8758767

  6. Brain polyphosphoinositide metabolism during focal ischemia in rat cortex

    SciTech Connect

    Lin, T.N.; Liu, T.H.; Xu, J.; Hsu, C.Y.; Sun, G.Y. )

    1991-04-01

    Using a rat model of stroke, we examined the effects of focal cerebral ischemia on the metabolism of polyphosphoinositides by injecting {sup 32}Pi into both the left and right cortices. After equilibration of the label for 2-3 hours, ischemia induced a significant decrease (p less than 0.001) in the concentrations of labeled phosphatidyl 4,5-bisphosphates (66-78%) and phosphatidylinositol 4-phosphate (64-67%) in the right middle cerebral artery cortex of four rats. The phospholipid labeling pattern in the left middle cerebral artery cortex, which sustained only mild ischemia and no permanent tissue damage, was not different from that of two sham-operated controls. However, when {sup 32}Pi was injected 1 hour after the ischemic insult, there was a significant decrease (p less than 0.01) in the incorporation of label into the phospholipids in both cortices of four ischemic rats compared with four sham-operated controls. Furthermore, differences in the phospholipid labeling pattern were observed in the left cortex compared with the sham-operated controls. The change in labeling pattern was attributed to the partial reduction in blood flow following ligation of the common carotid arteries. We provide a sensitive procedure for probing the effects of focal cerebral ischemia on the polyphosphoinositide signaling pathway in the brain, which may play an important role in the pathogenesis of tissue injury.

  7. Effect of exposure to diazinon on adult rat's brain.

    PubMed

    Rashedinia, Marzieh; Hosseinzadeh, Hossein; Imenshahidi, Mohsen; Lari, Parisa; Razavi, Bibi Marjan; Abnous, Khalil

    2016-04-01

    Diazinon (DZN), a commonly used agricultural organophosphate insecticide, is one of the major concerns for human health. This study was planned to investigate neurotoxic effects of subacute exposure to DZN in adult male Wistar rats. Animals received corn oil as control and 15 and 30 mg/kg DZN orally by gastric gavage for 4 weeks. The cerebrum malondialdehyde and glutathione (GSH) contents were assessed as biomarkers of lipid peroxidation and nonenzyme antioxidants, respectively. Moreover, activated forms of caspase 3, -9, and Bax/Bcl-2 ratios were evaluated as key apoptotic proteins. Results of this study suggested that chronic administration of DZN did not change lipid peroxidation and GSH levels significantly in comparison with control. Also, the active forms of caspase 3 and caspase 9 were not significantly altered in DZN-treated rat groups. Moreover, no significant changes were observed in Bax and Bcl-2 ratios. This study indicated that generation of reactive oxygen species was probably modulated by intracellular antioxidant system. In conclusion, subacute oral administration of DZN did not alter lipid peroxidation. Moreover, apoptosis induction was not observed in rat brain. PMID:24217015

  8. Kyotorphin (tyrosine-arginine) synthetase in rat brain synaptosomes.

    PubMed

    Ueda, H; Yoshihara, Y; Fukushima, N; Shiomi, H; Nakamura, A; Takagi, H

    1987-06-15

    Kyotorphin (Tyr-Arg) is a unique neuropeptide which produces analgesia by releasing Met-enkephalin from slices of the brain and spinal cord. Recent studies revealed that kyotorphin possesses the properties of neurotransmitter/neuroregulator. In the present study, we identified a kyotorphin synthetase in the soluble fraction of rat brain synaptosomes (synaptosol) and characterized it. The enzyme partially purified with Sephacryl S-300 showed an absolute requirement for ATP, MgCl2, tyrosine, and arginine. The optimal pH was 7.5-9.0 and the pI was determined to be 6.1-6.2 by isoelectric focusing. The Km was 25.6 microM for tyrosine, 926 microM for arginine, 294 microM for ATP, and 442 microM for MgCl2. The Vmax was 34.0 pmol/mg of protein/h. The apparent molecular size of this "kyotorphin synthetase" further purified by the DE52 column was 240,000-245,000 daltons, estimated using TSKgel G4000SW column chromatography. The enzyme reaction is represented by the following equation: Tyr + Arg + ATP + MgCl2 + kyotorphin synthetase----Tyr-Arg (kyotorphin) + AMP + PPi + MgCl2 + kyotorphin synthetase. The regional distribution and subcellular localization of the synthetase showed a close correlation to that of kyotorphin levels in the rat brain. The amounts of kyotorphin formed from amino acids by the synthetase in the dialyzed synaptosol was 3.0-4.0 times higher than that from precursor proteins by processing enzymes within the 30 min incubation. PMID:3597366

  9. An improved filtration procedure for measuring opiate receptors in small regions of rat brain.

    PubMed

    Bardo, M T; Bhatnagar, R K; Gebhart, G F

    1982-12-01

    A modified filtration method for in vitro receptor binding was used to determine specific binding of [3H]naloxone to small regions of adult rat brain. Reliable determinations of ligand binding were quantified with about 50 micrograms of protein per assay tube. Large differences in [3H]naloxone binding were obtained between various brain nuclei, and these differences were consistent with prior determinations of opiate receptor densities in various rat brain nuclei using autoradiographic techniques. PMID:6292368

  10. Citrobacter koseri Brain Abscess in the Neonatal Rat: Survival and Replication within Human and Rat Macrophages

    PubMed Central

    Townsend, Stacy M.; Pollack, Harvey A.; Gonzalez-Gomez, Ignacio; Shimada, Hiroyuki; Badger, Julie L.

    2003-01-01

    A unique feature of Citrobacter koseri is the extremely high propensity to initiate brain abscesses during neonatal meningitis. Previous clinical reports and studies on infant rats have documented many Citrobacter-filled macrophages within the ventricles and brain abscesses. It has been hypothesized that intracellular survival and replication within macrophages may be a mechanism by which C. koseri subverts the host response and elicits chronic infection, resulting in brain abscess formation. In this study, we showed that C. koseri causes meningitis and brain abscesses in the neonatal rat model, and we utilized histology and magnetic resonance imaging technology to visualize brain abscess formation. Histology and electron microscopy (EM) revealed that macrophages (and not fibroblasts, astrocytes, oligodendrocytes, or neurons) were the primary target for long-term C. koseri infection. To better understand C. koseri pathogenesis, we have characterized the interactions of C. koseri with human macrophages. We found that C. koseri survives and replicates within macrophages in vitro and that uptake of C. koseri increases in the presence of human pooled serum in a dose-dependent manner. EM studies lend support to the hypothesis that C. koseri uses morphologically different methods of uptake to enter macrophages. FcγRI blocking experiments show that this receptor primarily facilitates the entry of opsonized C. koseri into macrophages. Further, confocal fluorescence microscopy demonstrates that C. koseri survives phagolysosomal fusion and that more than 90% of intracellular C. koseri organisms are colocalized within phagolysosomes. The ability of C. koseri to survive phagolysosome fusion and replicate within macrophages may contribute to the establishment of chronic central nervous system infection including brain abscesses.   PMID:14500508

  11. A scanning SAXS/WAXS study of rat brain

    NASA Astrophysics Data System (ADS)

    Yagi, Naoto

    2011-01-01

    A simultaneous SAXS (small-angle X-ray scattering) and WAXS (wide-angle X-ray scattering) measurement setup was installed at BL45XU in SPring-8. The system comprises of a short (specimen-to-sample distance about 50cm) vacuum path and a mosaic CCD detector. It covers a q-range of 0.02-2.5 nm-1. Using this setup, lipids in formalin-fixed rat brain were analyzed. A brain slice was moved across the X-ray beam with a step size of 0.5 mm to map reflections from lipids in various areas of brain. White matter that contains myelin gave strong lamellar reflections in the small-angle region which are often unisotropic. Gray matter shows only a central scatter in the small-angle region. In the wide angle region, both white and gray matters gave rise to sharp rings that are due to lateral packing of hydrocarbon chains in the lipid membranes. The relative intensities of these rings were different in white and gray matters, showing that the lateral arrangements of the lipids in bilayers are different.

  12. Maturation of metabolic connectivity of the adolescent rat brain

    PubMed Central

    Choi, Hongyoon; Choi, Yoori; Kim, Kyu Wan; Kang, Hyejin; Hwang, Do Won; Kim, E Edmund; Chung, June-Key; Lee, Dong Soo

    2015-01-01

    Neuroimaging has been used to examine developmental changes of the brain. While PET studies revealed maturation-related changes, maturation of metabolic connectivity of the brain is not yet understood. Here, we show that rat brain metabolism is reconfigured to achieve long-distance connections with higher energy efficiency during maturation. Metabolism increased in anterior cerebrum and decreased in thalamus and cerebellum during maturation. When functional covariance patterns of PET images were examined, metabolic networks including default mode network (DMN) were extracted. Connectivity increased between the anterior and posterior parts of DMN and sensory-motor cortices during maturation. Energy efficiency, a ratio of connectivity strength to metabolism of a region, increased in medial prefrontal and retrosplenial cortices. Our data revealed that metabolic networks mature to increase metabolic connections and establish its efficiency between large-scale spatial components from childhood to early adulthood. Neurodevelopmental diseases might be understood by abnormal reconfiguration of metabolic connectivity and efficiency. DOI: http://dx.doi.org/10.7554/eLife.11571.001 PMID:26613413

  13. Heatstroke Effect on Brain Heme Oxygenase-1 in Rats.

    PubMed

    Wen, Ya-Ting; Liu, Tsung-Ta; Lin, Yuh-Feng; Chen, Chun-Chi; Kung, Woon-Man; Huang, Chi-Chang; Lin, Tien-Jen; Wang, Yuan-Hung; Wei, Li

    2015-01-01

    Exposure to high environmental temperature leading to increased core body temperature above 40°C and central nervous system abnormalities such as convulsions, delirium, or coma is defined as heat stroke. Studies in humans and animals indicate that the heat shock responses of the host contribute to multiple organ injury and death during heat stroke. Heme oxygenase-1 (HO-1)-a stress-responsive enzyme that catabolizes heme into iron, carbon monoxide, and biliverdin-has an important role in the neuroprotective mechanism against ischemic stroke. Here, we investigated the role of endogenous HO-1 in heat-induced brain damage in rats. RT-PCR results revealed that levels of HO-1 mRNA peaked at 0 h after heat exposure and immunoblot analysis revealed that the maximal protein expression occurred at 1 h post-heat exposure. Subsequently, we detected the HO-1 expression in the cortical brain cells and revealed the neuronal cell morphology. In conclusion, HO-1 is a potent protective molecule against heat-induced brain damage. Manipulation of HO-1 may provide a potential therapeutic approach for heat-related diseases. PMID:26392811

  14. In vivo deep brain imaging of rats using oral-cavity illuminated photoacoustic computed tomography

    NASA Astrophysics Data System (ADS)

    Lin, Li; Xia, Jun; Wong, Terence T. W.; Zhang, Ruiying; Wang, Lihong V.

    2015-03-01

    We demonstrate, by means of internal light delivery, photoacoustic imaging of the deep brain of rats in vivo. With fiber illumination via the oral cavity, we delivered light directly into the bottom of the brain, much more than can be delivered by external illumination. The study was performed using a photoacoustic computed tomography (PACT) system equipped with a 512-element full-ring transducer array, providing a full two-dimensional view aperture. Using internal illumination, the PACT system provided clear cross sectional photoacoustic images from the palate to the middle brain of live rats, revealing deep brain structures such as the hypothalamus, brain stem, and cerebral medulla.

  15. Continuous and simultaneous electrochemical measurements of glucose, lactate, and ascorbate in rat brain following brain ischemia.

    PubMed

    Lin, Yuqing; Yu, Ping; Hao, Jie; Wang, Yuexiang; Ohsaka, Takeo; Mao, Lanqun

    2014-04-15

    Developing new tools and technologies to enable recording the dynamic changes of multiple neurochemicals is the essence of better understanding of the molecular basis of brain functions. This study demonstrates a microfluidic chip-based online electrochemical system (OECS) for in vivo continuous and simultaneous monitoring of glucose, lactate, and ascorbate in rat brain. To fabricate the microfluidic chip-based detecting system, a microfluidic chip with patterned channel is developed into an electrochemical flow cell by incorporating the chip with three surface-modified indium-tin oxide (ITO) electrodes as working electrodes, a Ag/AgCl wire as reference electrode, and a stainless steel tube as counter electrode. Selective detection of ascorbate is achieved by the use of single-walled carbon nanotubes (SWNTs) to largely facilitate the electrochemical oxidation of ascorbate, while a dehydrogenase-based biosensing mechanism with methylene green (MG) adsorbed onto SWNTs as an electrocatalyst for the oxidation of dihydronicotiamide adenine dinucleotide (NADH) is employed for biosensing of glucose and lactate. To avoid the crosstalk among three sensors, the sensor alignment is carefully designed with the SWNT-modified electrode in the upstream channel and paralleled glucose and lactate biosensors in the downstream channels. With the microfluidic chip-based electrochemical flow cell as the detector, an OECS is successfully established by directly integrating the microfluidic chip-based electrochemical flow cell with in vivo microdialysis. The OECS exhibits a good linear response toward glucose, lactate, and ascorbate with less crosstalk. This property, along with the high stability and selectivity, enables the OECS for continuously monitoring three species in rat brain following brain ischemia. PMID:24621127

  16. Reduction in brain immunoreactive corticotropin-releasing factor (CRF) in spontaneously hypertensive rats

    SciTech Connect

    Hashimoto, K.; Hattori, T.; Murakami, K.; Suemaru, S.; Kawada, Y.; Kageyama, J.; Ota, Z.

    1985-02-18

    The brain CRF concentration of spontaneously hypertensive rats (SHR) and normotensive Wistar Kyoto rats (WKY) was examined by rat CRF radioimmunoassay. Anti-CRF serum was developed by immunizing rabbits with synthetic rat CRF. Synthetic rat CRF was also used as tracer and standard. The displacement of /sup 125/I-rat CRF by serially diluted extracts of male Wistar rats hypothalamus, thalamus, midbrain, pons, medulla oblongata, cerebral cortex, cerebellum and neurointermediate lobe was parallel to the displacement of synthetic rat CRF. In both WKY and SHR the highest levels of CRF immunoreactivity were shown by the hypothalamus and neurointermediate lobe, and considerable CRF immunoreactivity was also detected in other brain regions. The CRF immunoreactivity in the hypothalamus, neurointermediate lobe, midbrain, medulla oblongata and cerebral cortex was significantly reduced in SHR and it may suggest that CRF abnormality may be implicated in the reported abnormalities in the pituitary-adrenal axis, autonomic response and behavior of SHR.

  17. Voltammetric detection of 5-hydroxytryptamine release in the rat brain.

    PubMed

    Hashemi, Parastoo; Dankoski, Elyse C; Petrovic, Jelena; Keithley, Richard B; Wightman, R M

    2009-11-15

    5-Hydroxytryptamine (5-HT) is an important molecule in the brain that is implicated in mood and emotional processes. In vivo, its dynamic release and uptake kinetics are poorly understood due to a lack of analytical techniques for its rapid measurement. Whereas fast-scan cyclic voltammetry with carbon fiber microelectrodes is used frequently to monitor subsecond dopamine release in freely moving and anesthetized rats, the electrooxidation of 5-HT forms products that quickly polymerize and irreversibly coat the carbon electrode surface. Previously described modifications of the electrochemical waveform allow stable and sensitive 5-HT measurements in mammalian tissue slice preparations and in the brain of fruit fly larvae. For in vivo applications in mammals, however, the problem of electrode deterioration persists. We identify the root of this problem to be fouling by extracellular metabolites such as 5-hydoxyindole acetic acid (5-HIAA), which is present in 200-1000 times the concentration of 5-HT and displays similar electrochemical properties, including filming of the electrode surface. To impede access of the 5-HIAA to the electrode surface, a thin layer of Nafion, a cation exchange polymer, has been electrodeposited onto cylindrical carbon-fiber microelectrodes. The presence of the Nafion film was confirmed with environmental scanning electron microscopy and was demonstrated by the diminution of the voltammetric signals for 5-HIAA as well as other common anionic species. The modified microelectrodes also display increased sensitivity to 5-HT, yielding a characteristic cyclic voltammogram that is easily distinguishable from other common electroactive brain species. The thickness of the Nafion coating and a diffusion coefficient (D) in the film for 5-HT were evaluated by measuring permeation through Nafion. In vivo, we used physiological, anatomical, and pharmacological evidence to validate the signal as 5-HT. Using Nafion-modified microelectrodes, we present the

  18. Microbubbles coupled to methotrexate-loaded liposomes for ultrasound-mediated delivery of methotrexate across the blood–brain barrier

    PubMed Central

    Wang, Xiang; Liu, Ping; Yang, Weixiao; Li, Lu; Li, Peijing; Liu, Zheng; Zhuo, Zhongxiong; Gao, Yunhua

    2014-01-01

    Methotrexate (MTX) is the single most effective agent for the treatment of primary central nervous system lymphoma. Currently, the delivery of MTX to the brain is achieved by high systemic doses, which cause severe long-term neurotoxicity, or intrathecal administration, which is highly invasive and may lead to infections or hemorrhagic complications. Acoustically active microbubbles have been developed as drug carriers for the noninvasive and brain-targeted delivery of therapeutics. However, their application is limited by their low drug-loading capacity. To overcome this limitation, we prepared microbubbles coupled to MTX-loaded liposomes using ZHIFUXIAN, a novel type of microbubbles with a superior safety profile and long circulation time. MTX-liposome-coupled microbubbles had a high drug-loading capacity of 8.91%±0.86%, and their size (2.64±0.93 μm in diameter) was suitable for intravenous injection. When used with ultrasound, they showed more potent in vitro cytotoxicity against Walker-256 cancer cells than MTX alone or MTX-loaded liposomes. When Sprague-Dawley rats were exposed to sonication, administration of these MTX-liposome-coupled microbubbles via the tail vein led to targeted disruption of the blood–brain barrier without noticeable tissue or capillary damage. High-performance liquid chromatography analysis of the brain MTX concentration showed that MTX delivery to the brain followed the order of MTX-liposome-coupled microbubbles + ultrasound (25.3±2.4 μg/g) > unmodified ZHIFUXIAN + MTX + ultrasound (18.6±2.2 μg/g) > MTX alone (6.97±0.75 μg/g) > MTX-liposome-coupled microbubbles (2.92±0.39 μg/g). Therefore, treatment with MTX-liposome-coupled microbubbles and ultrasound resulted in a significantly higher brain MTX concentration than all other treatments (P<0.01). These results suggest that MTX-liposome-coupled microbubbles may hold great promise as new and effective therapies for primary central nervous system lymphoma and other central

  19. Differential changes of metabolic brain activity and interregional functional coupling in prefronto-limbic pathways during different stress conditions: functional imaging in freely behaving rodent pups

    PubMed Central

    Bock, Jörg; Riedel, Anett; Braun, Katharina

    2012-01-01

    The trumpet-tailed rat or degu (Octodon degus) is an established model to investigate the consequences of early stress on the development of emotional brain circuits and behavior. The aim of this study was to identify brain circuits, that respond to different stress conditions and to test if acute stress alters functional coupling of brain activity among prefrontal and limbic regions. Using functional imaging (2-Fluoro-deoxyglucose method) in 8-day-old male degu pups the following stress conditions were compared: (A) pups together with parents and siblings (control), (B) separation of the litter from the parents, (C) individual separation from parents and siblings, and (D) individual separation and presentation of maternal calls. Condition (B) significantly downregulated brain activity in the prefrontal cortex, hippocampus, nucleus accumbens (NAcc), and sensory areas compared to controls. Activity decrease was even more pronounced during condition (C), where, in contrast to all other regions, activity in the PAG was increased. Interestingly, brain activity in stress-associated brain regions such as the amygdala and habenula was not affected. In condition (D) maternal vocalizations “reactivated” brain activity in the cingulate and precentral medial cortex, NAcc, and striatum and in sensory areas. In contrast, reduced activity was measured in the prelimbic and infralimbic cortex (IL) and in the hippocampus and amygdala. Correlation analysis revealed complex, region- and situation-specific changes of interregional functional coupling among prefrontal and limbic brain regions during stress exposure. We show here for the first time that early life stress results in a widespread reduction of brain activity in the infant brain and changes interregional functional coupling. Moreover, maternal vocalizations can partly buffer stress-induced decrease in brain activity in some regions and evoked very different functional coupling patterns compared to the three other

  20. NMR-Based Metabolic Profiling Reveals Neurochemical Alterations in the Brain of Rats Treated with Sorafenib.

    PubMed

    Du, Changman; Shao, Xue; Zhu, Ruiming; Li, Yan; Zhao, Qian; Fu, Dengqi; Gu, Hui; Kong, Jueying; Luo, Li; Long, Hailei; Deng, Pengchi; Wang, Huijuan; Hu, Chunyan; Zhao, Yinglan; Cen, Xiaobo

    2015-11-01

    Sorafenib, an active multi-kinase inhibitor, has been widely used as a chemotherapy drug to treat advanced clear-cell renal cell carcinoma patients. In spite of the relative safety, sorafenib has been shown to exert a negative impact on cognitive functioning in cancer patients, specifically on learning and memory; however, the underlying mechanism remains unclear. In this study, an NMR-based metabolomics approach was applied to investigate the neurochemical effects of sorafenib in rats. Male rats were once daily administrated with 120 mg/kg sorafenib by gavage for 3, 7, and 28 days, respectively. NMR-based metabolomics coupled with histopathology examinations for hippocampus, prefrontal cortex (PFC), and striatum were performed. The (1)H NMR spectra data were analyzed by using multivariate pattern recognition techniques to show the time-dependent biochemical variations induced by sorafenib. Excellent separation was obtained and distinguishing metabolites were observed between sorafenib-treated and control rats. A total of 36 differential metabolites in hippocampus of rats treated with sorafenib were identified, some of which were significantly changed. Furthermore, these modified metabolites mainly reflected the disturbances in neurotransmitters, energy metabolism, membrane, and amino acids. However, only a few metabolites in PFC and striatum were altered by sorafenib. Additionally, no apparent histological changes in these three brain regions were observed in sorafenib-treated rats. Together, our findings demonstrate the disturbed metabonomics pathways, especially, in hippocampus, which may underlie the sorafenib-induced cognitive deficits in patients. This work also shows the advantage of NMR-based metabolomics over traditional approach on the study of biochemical effects of drugs. PMID:26233726

  1. Sex Differences in Serotonin 1 Receptor Binding in Rat Brain

    NASA Astrophysics Data System (ADS)

    Fischette, Christine T.; Biegon, Anat; McEwen, Bruce S.

    1983-10-01

    Male and female rats exhibit sex differences in binding by serotonin 1 receptors in discrete areas of the brain, some of which have been implicated in the control of ovulation and of gonadotropin release. The sex-specific changes in binding, which occur in response to the same hormonal (estrogenic) stimulus, are due to changes in the number of binding sites. Castration alone also affects the number of binding sites in certain areas. The results lead to the conclusion that peripheral hormones modulate binding by serotonin 1 receptors. The status of the serotonin receptor system may affect the reproductive capacity of an organism and may be related to sex-linked emotional disturbances in humans.

  2. Methylglyoxal can mediate behavioral and neurochemical alterations in rat brain.

    PubMed

    Hansen, Fernanda; Pandolfo, Pablo; Galland, Fabiana; Torres, Felipe Vasconcelos; Dutra, Márcio Ferreira; Batassini, Cristiane; Guerra, Maria Cristina; Leite, Marina Concli; Gonçalves, Carlos-Alberto

    2016-10-01

    Diabetes is associated with loss of cognitive function and increased risk for Alzheimer's disease (AD). Advanced glycation end products (AGEs) are elevated in diabetes and AD and have been suggested to act as mediators of the cognitive decline observed in these pathologies. Methylglyoxal (MG) is an extremely reactive carbonyl compound that propagates glycation reactions and is, therefore, able to generate AGEs. Herein, we evaluated persistent behavioral and biochemical parameters to explore the hypothesis that elevated exogenous MG concentrations, induced by intracerebroventricular (ICV) infusion, lead to cognitive decline in Wistar rats. A high and sustained administration of MG (3μmol/μL; subdivided into 6days) was found to decrease the recognition index of rats, as evaluated by the object-recognition test. However, MG was unable to impair learning-memory processes, as shown by the habituation in the open field (OF) and Y-maze tasks. Moreover, a single high dose of MG induced persistent alterations in anxiety-related behavior, diminishing the anxiety-like parameters evaluated in the OF test. Importantly, MG did not alter locomotion behavior in the different tasks performed. Our biochemical findings support the hypothesis that MG induces persistent alterations in the hippocampus, but not in the cortex, related to glyoxalase 1 activity, AGEs content and glutamate uptake. Glial fibrillary acidic protein and S100B content, as well as S100B secretion (astroglial-related parameters of brain injury), were not altered by ICV MG administration. Taken together, our data suggest that MG interferes directly in brain function and that the time and the levels of exogenous MG determine the different features that can be seen in diabetic patients. PMID:27235733

  3. Two-photon microscopy as a tool to study blood flow and neurovascular coupling in the rodent brain

    PubMed Central

    Shih, Andy Y; Driscoll, Jonathan D; Drew, Patrick J; Nishimura, Nozomi; Schaffer, Chris B; Kleinfeld, David

    2012-01-01

    The cerebral vascular system services the constant demand for energy during neuronal activity in the brain. Attempts to delineate the logic of neurovascular coupling have been greatly aided by the advent of two-photon laser scanning microscopy to image both blood flow and the activity of individual cells below the surface of the brain. Here we provide a technical guide to imaging cerebral blood flow in rodents. We describe in detail the surgical procedures required to generate cranial windows for optical access to the cortex of both rats and mice and the use of two-photon microscopy to accurately measure blood flow in individual cortical vessels concurrent with local cellular activity. We further provide examples on how these techniques can be applied to the study of local blood flow regulation and vascular pathologies such as small-scale stroke. PMID:22293983

  4. Proteomic analysis of immature rat pups brain in response to hypoxia and ischemia challenge

    PubMed Central

    Yang, Li-Jun; Ma, Dong-Qing; Cui, Hong

    2014-01-01

    Hypoxia and ischemia significantly affects perinatal brain development, even worse in preterm infants. However, the details of the mechanism leading to permanent brain damage after hypoxia-ischemia attack have not been fully elucidated. Proteomics could provide insight into the potential mechanism and help to promote the clinical treatment. In this study, quantitative analysis was performed 24 hours after hypoxia-ischemia using liquid-chromatography mass spectrometry coupled to label-free analysis. Compared to control, 193 proteins were present only in hypoxic-ischemic group. In addition, 34 proteins were more than 2 folds up-regulated and 14 proteins were more than 2 folds down-regulated in hypoxia-ischemia group. Gene Ontology database showed that the majority of differentially expressed proteins comprised mitochondrial proteins et al. Molecular function analysis revealed that the majority of proteins were involved in ion binding et al. Biological process analysis showed that the majority of proteins were involved in response to organic substance et al. STRING 9.0 software analysis were used to explore the complex interactions existed among the proteins. Western blot were used to verify the fold changes of some proteins-microtubule-associated protein 2 and microtubule-associated protein tau. This novel study performed a full-scale screening of the proteomics research in hypoxic-ischemic brain damage of immature rat. PMID:25197337

  5. Are soluble and membrane-bound rat brain acetylcholinesterase different

    SciTech Connect

    Andres, C.; el Mourabit, M.; Stutz, C.; Mark, J.; Waksman, A. )

    1990-11-01

    Salt-soluble and detergent-soluble acetylcholinesterases (AChE) from adult rat brain were purified to homogeneity and studied with the aim to establish the differences existing between these two forms. It was found that the enzymatic activities of the purified salt-soluble AChE as well as the detergent-soluble AChE were dependent on the Triton X-100 concentration. Moreover, the interaction of salt-soluble AChE with liposomes suggests amphiphilic behaviour of this enzyme. Serum cholinesterase (ChE) did not bind to liposomes but its activity was also detergent-dependent. Detergent-soluble AChE remained in solution below critical micellar concentrations of Triton X-100. SDS polyacrylamide gel electrophoresis of purified, Biobeads-treated and iodinated detergent-soluble 11 S AChE showed, under non reducing conditions, bands of 69 kD, 130 kD and greater than 250 kD corresponding, respectively, to monomers, dimers and probably tetramers of the same polypeptide chain. Under reducing conditions, only a 69 kD band was detected. It is proposed that an amphiphilic environment stabilizes the salt-soluble forms of AChE in the brain in vivo and that detergent-soluble Biobeads-treated 11 S AChE possess hydrophobic domain(s) different from the 20 kD peptide already described.

  6. Brain Pathology in Adult Rats Treated With Domoic Acid.

    PubMed

    Vieira, A C; Alemañ, N; Cifuentes, J M; Bermúdez, R; Peña, M López; Botana, L M

    2015-11-01

    Domoic acid (DA) is a neurotoxin reported to produce damage to the hippocampus, which plays an important role in memory. The authors inoculated rats intraperitoneally with an effective toxic dose of DA to study the distribution of the toxin in major internal organs by using immunohistochemistry, as well as to evaluate the induced pathology by means of histopathologic and immunohistochemical methods at different time points after toxin administration (6, 10, and 24 hours; 5 and 54 days). DA was detected by immunohistochemistry exclusively in pyramidal neurons of the hippocampus at 6 and 10 hours after dosing. Lesions induced by DA were prominent at 5 days following treatment in selected regions of the brain: hippocampus, amygdala, piriform and perirhinal cortices, olfactory tubercle, septal nuclei, and thalamus. The authors found 2 types of lesions: delayed death of selective neurons and large areas of necrosis, both accompanied by astrocytosis and microgliosis. At 54 days after DA exposure, the pathology was characterized by still-distinguishable dying neurons, calcified lesions in the thalamus, persistent astrocytosis, and pronounced microgliosis. The expression of nitric oxide synthases suggests a role for nitric oxide in the pathogenesis of neuronal degeneration and chronic inflammation induced by DA in the brain. PMID:25939577

  7. (1)H MRS in the rat brain under pentobarbital anesthesia: accurate quantification of in vivo spectra in the presence of propylene glycol.

    PubMed

    Iltis, Isabelle; Marjańska, Małgorzata; Du, Fei; Koski, Dee M; Zhu, Xiao-Hong; Ugurbil, Kâmil; Chen, Wei; Henry, Pierre-Gilles

    2008-03-01

    Commercial solutions for pentobarbital anesthesia typically contain water H spectra. The purpose of the present study was to measure the concentration of metabolites in the rat brain in vivo under pentobarbital anesthesia using 1H MRS. Resonances of PG, but not ethanol, were observed in the rat brain. Chemical shifts and J-coupling constants for PG were measured at 37 degrees C and pH 7.1 and used for spectral simulation. Inclusion of the simulated PG spectrum in the basis set for LCModel analysis enabled accurate fitting of in vivo spectra. This work demonstrates that concentration of brain metabolites can be reliably measured using 1H spectroscopy under pentobarbital anesthesia. The chemical shifts and J-coupling values reported here can be used to simulate the spectrum of PG at any field strength, with various pulse sequences. PMID:18224694

  8. Expression and distribution of TRPV2 in rat brain.

    PubMed

    Nedungadi, Thekkethil Prashant; Dutta, Mayurika; Bathina, Chandra Sekhar; Caterina, Michael J; Cunningham, J Thomas

    2012-09-01

    Transient receptor potential (TRP) proteins are non-selective cation channels that mediate sensory transduction. The neuroanatomical localization and the physiological roles of isoform TRPV2 in the rodent brain are largely unknown. We report here the neuroanatomical distribution of TRPV2 in the adult male rat brain focusing on the hypothalamus and hindbrain regions involved in osmoregulation, autonomic function and energy metabolism. For this we utilized immunohistochemistry combined with brightfield microscopy. In the forebrain, the densest immunostaining was seen in both the supraoptic nucleus (SON) and the magnocellular division of the paraventricular nucleus (PVN) of the hypothalamus. TRPV2 immunoreactivity was also seen in the organum vasculosum of the lamina terminalis, the median preoptic nucleus and the subfornical organ, in addition to the arcuate nucleus of the hypothalamus (ARH), the medial forebrain bundle, the cingulate cortex and the globus pallidus to name a few. In the hindbrain, intense staining was seen in the nucleus of the solitary tract, hypoglossal nucleus, nucleus ambiguous, and the rostral division of the ventrolateral medulla (RVLM) and some mild staining in the area prostrema. To ascertain the specificity of the TRPV2 antibody used in this paper, we compared the TRPV2 immunoreactivity of wildtype (WT) and knockout (KO) mouse brain tissue. Double immunostaining with arginine vasopressin (AVP) using confocal microscopy showed a high degree of colocalization of TRPV2 in the magnocellular SON and PVN. Using laser capture microdissection (LCM) we also show that AVP neurons in the SON contain TRPV2 mRNA. TRPV2 was also co-localized with dopamine beta hydroxylase (DBH) in the NTS and the RVLM of the hindbrain. Based on our results, TRPV2 may play an important role in several CNS networks that regulate body fluid homeostasis, autonomic function, and metabolism. PMID:22750329

  9. Subcellular localization and compartmentation of thiamine derivatives in rat brain.

    PubMed

    Bettendorff, L; Wins, P; Lesourd, M

    1994-05-26

    The subcellular distribution of thiamine derivatives in rat brain was studied. Thiamine diphosphate content was highest in the mitochondrial and synaptosomal fractions, and lowest in microsomal, myelin and cytosolic fractions. Only 3-5% of total thiamine diphosphate was bound to transketolase, a cytosolic enzyme. Thiamine triphosphate was barely detectable in the microsomal and cytosolic fraction, but synaptosomes were slightly enriched in this compound compared to the crude homogenate. Both myelin and mitochondrial fractions contained significant amounts of thiamine triphosphate. In order to estimate the relative turnover rates of these compounds, the animals received an intraperitoneal injection of either [14C]thiamine or [14C]sulbutiamine (isobutyrylthiamine disulfide) 1 h before decapitation. The specific radioactivities of thiamine compounds found in the brain decreased in the order: thiamine > thiamine triphosphate > thiamine monophosphate > thiamine diphosphate. Incorporation of radioactivity into thiamine triphosphate was more marked with [14C]sulbutiamine than with [14C]thiamine. The highest specific radioactivity of thiamine diphosphate was found in the cytosolic fraction of the brain, though this pool represents less than 10% of total thiamine diphosphate. Cytosolic thiamine diphosphate had a twice higher specific radioactivity when [14C]sulbutiamine was used as precursor compared with thiamine though no significant differences were found in the other cellular compartments. Our results suggest the existence of two thiamine diphosphate pools: the bound cofactor pool is essentially mitochondrial and has a low turnover; a much smaller cytosolic pool (6-7% of total TDP) of high turnover is the likely precursor of thiamine triphosphate. PMID:8186256

  10. Tannic acid alleviates lead acetate-induced neurochemical perturbations in rat brain.

    PubMed

    Ashafaq, Mohammad; Tabassum, Heena; Vishnoi, Shruti; Salman, Mohd; Raisuddin, Sheikh; Parvez, Suhel

    2016-03-23

    Oxidative stress has been projected as a promising mechanism involved in lead exposure. The lead predisposition catalyzes oxidative reactions and generates reactive oxygen species. The present study was carried out to investigate the effect of oral administration of tannic acid (TA) on behavioral deficit, antioxidative deterioration induced by lead acetate (LA) exposure on experimental rat brain. Male Wistar rats were treated with 50mg/kg body weight of LA and TA for three times a week for two weeks. Our data showed LA-induced profound elevation of ROS production and oxidative stress, as evidenced by increased levels of oxidative stress markers such as lipid peroxidation and protein carbonyl observed in LA treated rats, whereas significant depletion in the activity of non-enzymatic antioxidants, enzymatic antioxidants, neurotoxicity biomarker and histological changes were observed in LA treated rat brain. However, TA administration restored antioxidant status of brain significantly when compared to control. Our results demonstrate that TA exhibits potent antioxidant properties and suppresses oxidative damages in rat brain induced by LA treatment. These findings were further supported by the neurotoxicity biomarker and histopathological findings in the brain tissue showed that TA protected tissue from deleterious effects of LA exposure. It is concluded, these data suggest that LA induces oxidative stress and supplementation of TA has a powerful antioxidant effect, and it protected rat brain from poisonous effect of LA exposure in experimental rat. PMID:26851560

  11. Glucose and amino acid metabolism in rat brain during sustained hypoglycemia

    SciTech Connect

    Wong, K.L.; Tyce, G.M.

    1983-04-01

    The metabolism of glucose in brains during sustained hypoglycemia was studied. (U-/sup 14/C)Glucose (20 microCi) was injected into control rats, and into rats at 2.5 hr after a bolus injection of 2 units of insulin followed by a continuous infusion of 0.2 units/100 g rat/hr. This regimen of insulin injection was found to result in steady-state plasma glucose levels between 2.5 and 3.5 mumol per ml. In the brains of control rats carbon was transferred rapidly from glucose to glutamate, glutamine, gamma-aminobutyric acid and aspartate and this carbon was retained in the amino acids for at least 60 min. In the brains of hypoglycemic rats, the conversion of carbon from glucose to amino acids was increased in the first 15 min after injection. After 15 min, the specific activity of the amino acids decreased in insulin-treated rats but not in the controls. The concentrations of alanine, glutamate, and gamma-amino-butyric acid decreased, and the concentration of aspartate increased, in the brains of the hypoglycemic rats. The concentration of pyridoxal-5'-phosphate, a cofactor in many of the reactions whereby these amino acids are formed from tricarboxylic acid cycle intermediates, was less in the insulin-treated rats than in the controls. These data provide evidence that glutamate, glutamine, aspartate, and GABA can serve as energy sources in brain during insulin-induced hypoglycemia.

  12. The Effects of Shilajit on Brain Edema, Intracranial Pressure and Neurologic Outcomes following the Traumatic Brain Injury in Rat

    PubMed Central

    Khaksari, Mohammad; Mahmmodi, Reza; Shahrokhi, Nader; Shabani, Mohammad; Joukar, Siavash; Aqapour, Mobin

    2013-01-01

    Objective(s): Brain edema is one of the most serious causes of death within the first few days after trauma brain injury (TBI). In this study we have investigated the role of Shilajit on brain edema, blood-brain barrier (BBB) permeability, intracranial pressure (ICP) and neurologic outcomes following brain trauma. Materials and Methods: Diffuse traumatic brain trauma was induced in rats by drop of a 250 g weight from a 2 m high (Marmarou’s methods). Animals were randomly divided into 5 groups including sham, TBI, TBI-vehicle, TBI-Shi150 group and TBI-Shi250 group. Rats were undergone intraperitoneal injection of Shilajit and vehicle at 1, 24, 48 and 72 hr after trauma. Brain water content, BBB permeability, ICP and neurologic outcomes were finally measured. Results: Brain water and Evans blue dye contents showed significant decrease in Shilajit-treated groups compared to the TBI-vehicle and TBI groups. Intracranial pressure at 24, 48 and 72 hr after trauma had significant reduction in Shilajit-treated groups as compared to TBI-vehicle and TBI groups (P<0.001). The rate of neurologic outcomes improvement at 4, 24, 48 and 72 hr after trauma showed significant increase in Shilajit-treated groups in comparison to theTBI- vehicle and TBI groups (P <0.001). Conclusion: The present results indicated that Shilajit may cause in improvement of neurologic outcomes through decreasing brain edema, disrupting of BBB, and ICP after the TBI. PMID:23997917

  13. Rat strain differences in brain structure and neurochemistry in response to binge alcohol

    PubMed Central

    Mayer, Dirk; Rohlfing, Torsten; Hsu, Oliver; Vinco, Shara; Orduna, Juan; Luong, Richard; Bell, Richard L; Sullivan, Edith V; Pfefferbaum, Adolf

    2013-01-01

    Rationale Ventricular enlargement is a robust phenotype of the chronically dependent alcoholic human brain, yet the mechanism of ventriculomegaly is unestablished. Heterogeneous stock Wistar rats administered binge EtOH (3 g/kg intragastrically every 8 h for 4 days to average blood alcohol levels (BALs) of 250 mg/dL) demonstrate profound but reversible ventricular enlargement and changes in brain metabolites (e.g., N-acetylaspartate (NAA) and choline-containing compounds (Cho)). Objectives Here, alcohol-preferring (P) and alcohol-nonpreferring (NP) rats systematically bred from heterogeneous stock Wistar rats for differential alcohol drinking behavior were compared with Wistar rats to determine whether genetic divergence and consequent morphological and neurochemical variation affect the brain’s response to binge EtOH treatment. Methods The three rat lines were dosed equivalently and approached similar BALs. Magnetic resonance imaging and spectroscopy evaluated the effects of binge EtOH on brain. Results As observed in Wistar rats, P and NP rats showed decreases in NAA. Neither P nor NP rats, however, responded to EtOH intoxication with ventricular expansion or increases in Cho levels as previously noted in Wistar rats. Increases in ventricular volume correlated with increases in Cho in Wistar rats. Conclusions The latter finding suggests that ventricular volume expansion is related to adaptive changes in brain cell membranes in response to binge EtOH. That P and NP rats responded differently to EtOH argues for intrinsic differences in their brain cell membrane composition. Further, differential metabolite responses to EtOH administration by rat strain implicate selective genetic variation as underlying heterogeneous effects of chronic alcoholism in the human condition. PMID:24030467

  14. Neurovascular and neuroimaging effects of the hallucinogenic serotonin receptor agonist psilocin in the rat brain.

    PubMed

    Spain, Aisling; Howarth, Clare; Khrapitchev, Alexandre A; Sharp, Trevor; Sibson, Nicola R; Martin, Chris

    2015-12-01

    The development of pharmacological magnetic resonance imaging (phMRI) has presented the opportunity for investigation of the neurophysiological effects of drugs in vivo. Psilocin, a hallucinogen metabolised from psilocybin, was recently reported to evoke brain region-specific, phMRI signal changes in humans. The present study investigated the effects of psilocin in a rat model using phMRI and then probed the relationship between neuronal and haemodynamic responses using a multimodal measurement preparation. Psilocin (2 mg/kg or 0.03 mg/kg i.v.) or vehicle was administered to rats (N=6/group) during either phMRI scanning or concurrent imaging of cortical blood flow and recording of local field potentials. Compared to vehicle controls psilocin (2 mg/kg) evoked phMRI signal increases in a number of regions including olfactory and limbic areas and elements of the visual system. PhMRI signal decreases were seen in other regions including somatosensory and motor cortices. Investigation of neurovascular coupling revealed that whilst neuronal responses (local field potentials) to sensory stimuli were decreased in amplitude by psilocin administration, concurrently measured haemodynamic responses (cerebral blood flow) were enhanced. The present findings show that psilocin evoked region-specific changes in phMRI signals in the rat, confirming recent human data. However, the results also suggest that the haemodynamic signal changes underlying phMRI responses reflect changes in both neuronal activity and neurovascular coupling. This highlights the importance of understanding the neurovascular effects of pharmacological manipulations for interpreting haemodynamic neuroimaging data. PMID:26192543

  15. Neurovascular and neuroimaging effects of the hallucinogenic serotonin receptor agonist psilocin in the rat brain

    PubMed Central

    Spain, Aisling; Howarth, Clare; Khrapitchev, Alexandre A.; Sharp, Trevor; Sibson, Nicola R.; Martin, Chris

    2015-01-01

    The development of pharmacological magnetic resonance imaging (phMRI) has presented the opportunity for investigation of the neurophysiological effects of drugs in vivo. Psilocin, a hallucinogen metabolised from psilocybin, was recently reported to evoke brain region-specific, phMRI signal changes in humans. The present study investigated the effects of psilocin in a rat model using phMRI and then probed the relationship between neuronal and haemodynamic responses using a multimodal measurement preparation. Psilocin (2 mg/kg or 0.03 mg/kg i.v.) or vehicle was administered to rats (N = 6/group) during either phMRI scanning or concurrent imaging of cortical blood flow and recording of local field potentials. Compared to vehicle controls psilocin (2 mg/kg) evoked phMRI signal increases in a number of regions including olfactory and limbic areas and elements of the visual system. PhMRI signal decreases were seen in other regions including somatosensory and motor cortices. Investigation of neurovascular coupling revealed that whilst neuronal responses (local field potentials) to sensory stimuli were decreased in amplitude by psilocin administration, concurrently measured haemodynamic responses (cerebral blood flow) were enhanced. The present findings show that psilocin evoked region-specific changes in phMRI signals in the rat, confirming recent human data. However, the results also suggest that the haemodynamic signal changes underlying phMRI responses reflect changes in both neuronal activity and neurovascular coupling. This highlights the importance of understanding the neurovascular effects of pharmacological manipulations for interpreting haemodynamic neuroimaging data. PMID:26192543

  16. Effects of radiofrequency radiation exposure on blood-brain barrier permeability in male and female rats.

    PubMed

    Sirav, Bahriye; Seyhan, Nesrin

    2011-12-01

    During the last several decades, numerous studies have been performed aiming at the question of whether or not exposure to radiofrequency radiation (RFR) influences the permeability of the blood-brain barrier (BBB). The objective of this study was to investigate the effect of RFR on the permeability of BBB in male and female Wistar albino rats. Right brain, left brain, cerebellum, and total brain were analyzed separately in the study. Rats were exposed to 0.9 and 1.8 GHz continuous-wave (CW) RFR for 20 min (at SARs of 4.26 mW/kg and 1.46 mW/kg, respectively) while under anesthesia. Control rats were sham-exposed. Disruption of BBB integrity was detected spectrophotometrically using the Evans-blue dye, which has been used as a BBB tracer and is known to be bound to serum albumin. Right brain, left brain, cerebellum, and total brain were evaluated for BBB permeability. In female rats, no albumin extravasation was found in in the brain after RFR exposure. A significant increase in albumin was found in the brains of the RF-exposed male rats when compared to sham-exposed male brains. These results suggest that exposure to 0.9 and 1.8 GHz CW RFR at levels below the international limits can affect the vascular permeability in the brain of male rats. The possible risk of RFR exposure in humans is a major concern for the society. Thus, this topic should be investigated more thoroughly in the future. PMID:22047463

  17. EFFECTS OF HYPERTHERMIA AND HYPERTHERMIA PLUS MICROWAVES ON RAT BRAIN ENERGY METABOLISM

    EPA Science Inventory

    The effects of hyperthermia, alone and in conjunction with microwave exposure, on brain energetics were studied in anesthetized male Sprague-Dawley rats. The effects of temperature on adenosine triphosphate concentration (ATP) and creatine phosphate concentration (CP) was determi...

  18. Low glucose utilization and neurodegenerative changes caused by sodium fluoride exposure in rat's developmental brain.

    PubMed

    Jiang, Chunyang; Zhang, Shun; Liu, Hongliang; Guan, Zhizhong; Zeng, Qiang; Zhang, Cheng; Lei, Rongrong; Xia, Tao; Wang, Zhenglun; Yang, Lu; Chen, Yihu; Wu, Xue; Zhang, Xiaofei; Cui, Yushan; Yu, Linyu; Wang, Aiguo

    2014-03-01

    Fluorine, a toxic and reactive element, is widely prevalent throughout the environment and can induce toxicity when absorbed into the body. This study was to explore the possible mechanisms of developmental neurotoxicity in rats treated with different levels of sodium fluoride (NaF). The rats' intelligence, as well as changes in neuronal morphology, glucose absorption, and functional gene expression within the brain were determined using the Morris water maze test, transmission electron microscopy, small-animal magnetic resonance imaging and Positron emission tomography and computed tomography, and Western blotting techniques. We found that NaF treatment-impaired learning and memory in these rats. Furthermore, NaF caused neuronal degeneration, decreased brain glucose utilization, decreased the protein expression of glucose transporter 1 and glial fibrillary acidic protein, and increased levels of brain-derived neurotrophic factor in the rat brains. The developmental neurotoxicity of fluoride may be closely associated with low glucose utilization and neurodegenerative changes. PMID:23982469

  19. ¹H NMR-based metabonomics in brain nucleus accumbens and striatum following repeated cocaine treatment in rats.

    PubMed

    Li, Y; Yan, G-Y; Zhou, J-Q; Bu, Q; Deng, P-C; Yang, Y-Z; Lv, L; Deng, Y; Zhao, J-X; Shao, X; Zhu, R-M; Huang, Y-N; Zhao, Y-L; Cen, X-B

    2012-08-30

    Studies have shown a few cerebral metabolites modified by cocaine in brain regions; however, endogenous metabolic profiling has been lacking. Ex vivo (1)H NMR (hydrogen-1 nuclear magnetic resonance) spectroscopy-based metabonomic approach coupled with partial least squares was applied to investigate the changes of cerebral metabolites in nucleus accumbens (NAc) and striatum of rats subjected to cocaine treatment. Our results showed that both single and repeated cocaine treatment can induce significant changes in a couple of cerebral metabolites. The increase of neurotransmitters glutamate and gamma-amino butyric acid (GABA) were observed in NAc and striatum from the rats repeatedly treated with cocaine. Creatine and taurine increased in NAc whereas taurine increased and creatine decreased in striatum after repeated cocaine treatment. Elevation of N-acetylaspartate in NAc and striatum and decrease of lactate in striatum were observed, which may reflect the mitochondria dysregulation caused by cocaine; moreover, alterations of choline, phosphocholine and glycerol in NAc and striatum could be related to membrane disruption. Moreover, groups of rats with and without conditioned place preference (CPP) apparatus are presenting difference in metabolites. Collectively, our results provide the first evidence of metabonomic profiling of NAc and striatum in response to cocaine, exhibiting a regionally-specific alteration patterns. We find that repeated cocaine administration leads to significant metabolite alterations, which are involved in neurotransmitter disturbance, oxidative stress, mitochondria dysregulation and membrane disruption in brain. PMID:22609933

  20. Different subcellular localization of muscarinic and serotonin (S2) receptors in human, dog, and rat brain.

    PubMed

    Luabeya, M K; Maloteaux, J M; De Roe, C; Trouet, A; Laduron, P M

    1986-02-01

    Cortex from rat, dog, and human brain was submitted to subcellular fractionation using an analytical approach consisting of a two-step procedure. First, fractions were obtained by differential centrifugation and were analyzed for their content of serotonin S2 and muscarinic receptors, serotonin uptake, and marker enzymes. Second, the cytoplasmic extracts were subfractionated by equilibration in sucrose density gradient. In human brain, serotonin and muscarinic receptors were found associated mostly with mitochondrial fractions which contain synaptosomes, whereas in rat brain they were concentrated mainly in the microsomal fractions. Density gradient centrifugation confirmed a more marked synaptosomal localization of receptors in human than in rat brain, the dog displaying an intermediate profile. In human brain, indeed, more receptor sites were found to be associated with the second peak characterized in electron microscopy by the largest number of nerve terminals. In addition, synaptosomes from human brain are denser than those from rat brain and some marker enzymes reveal different subcellular distribution in the three species. These data indicate that more receptors are of synaptosomal nature in human brain than in other species and this finding is compatible with a larger amount of synaptic contacts in human brain. PMID:2934515

  1. Iron-induced Necrotic Brain Cell Death in Rats with Different Aerobic Capacity

    PubMed Central

    Zheng, Mingzhe; Du, Hanjian; Ni, Wei; Koch, Lauren G.; Britton, Steven L.; Keep, Richard F.; Xi, Guohua; Hua, Ya

    2015-01-01

    Brain iron overload has a key role in brain injury after intracerebral hemorrhage (ICH). Our recent study demonstrated that ICH-induced brain injury was greater in low capacity runner (LCR) than in high capacity runner (HCR) rats. The present study examines whether iron-induced brain injury differs between LCRs and HCRs. Adult male LCR and HCR rats had an intracaudate injection of iron or saline. Rats were euthanized at 2 and at 24 hours after T2 magnetic resonance imaging and the brains were used for immunostaining and Western blotting. LCRs had more hemispheric swelling, T2 lesion volumes, blood-brain barrier disruption and neuronal death at 24 hours after iron injection (p < 0.05). Many propidium iodide (PI) positive cells, indicative of necrotic cell death, were observed in the ipsilateral basal ganglia of both HCRs and LCRs at 2 hours after iron injection. PI fluorescence intensity was higher in LCRs than in HCRs. In addition, membrane attack complex (MAC) expression was increased at 2 hours after iron injection and was higher in LCRs than in HCRs. The PI positive cells colocalized with MAC positive cells in the ipsilateral basal ganglia. Iron induces more severe necrotic brain cell death, brain swelling, and blood-brain barrier disruption in LCR rats, which may be related with complement activation and MAC formation. PMID:25649272

  2. Expression of aquaporin-4 and pathological characteristics of brain injury in a rat model of traumatic brain injury

    PubMed Central

    ZHANG, CHENGCHENG; CHEN, JIANQIANG; LU, HONG

    2015-01-01

    Aquaporin 4 (AQP4) is a widely distributed membrane protein, which is found in glial cells, ependymocytes and capillary endothelial cells in the brain, and particularly in the choroid plexus. AQP4 is a key regulator of water metabolism, and changes in its expression following brain injury are associated with pathological changes in the damaged side of the brain; however, the effects of brain injury on AQP4 and injury-induced pathological changes in the contralateral non-damaged side of the brain remain to be fully elucidated. In the present study, male Sprague-Dawley rats were subjected to traumatic brain injury (TBI) and changes in brain water content, the expression of AQP4 expression and pathological characteristics in the damaged and contralateral non-damaged sides of the brain were examined. In the damaged side of the brain, vasogenic edema appeared first, followed by cellular edema. The aggravated cellular edema in the damaged side of the brain resulted in two periods of peak edema severity. Pathological changes in the contralateral non-damaged side of the brain occurred later than those in the damaged side; cellular edema appeared first, followed by vasogenic edema, which was alleviated earlier than the cellular edema. AQP4 was downregulated during vasogenic edema, and upregulated during cellular edema. Taken together, these results suggested that the downregulation of AQP4 was a result of vasogenic edema and that the upregulation of AQP4 may have induced cellular edema. PMID:26459070

  3. Effects of Chronic Renal Failure on Brain Cytochrome P450 in Rats.

    PubMed

    Naud, Judith; Harding, Jessica; Lamarche, Caroline; Beauchemin, Stephanie; Leblond, Francois A; Pichette, Vincent

    2016-08-01

    Chronic renal failure (CRF) impedes renal excretion of drugs and their metabolism by reducing the expression of liver cytochrome P450 (P450). Uremic serum contains factors, such as parathyroid hormone (PTH), that decrease liver P450s. The P450s are also involved in the metabolism of xenobiotics in the brain. This study investigates: 1) the effects of CRF on rat brain P450, 2) the role of PTH in the downregulation of brain P450s in CRF rats, and 3) the effects of PTH on P450s in astrocytes. Protein and mRNA expression of P450s were assessed in the brain of CRF and control (CTL) rats, as well as from CTL or CRF rats that underwent parathyroidectomy (PTX) 1 week before nephrectomy. CYP3A activity was measured using 3-[(3, 4-difluorobenzyl) oxy]-5, 5-dimethyl-4-[4-methylsulfonyl) phenyl] furan-2(5H)-1 metabolism in brain microsomal preparation. CYP3A protein expression was assessed in primary cultured astrocytes incubated with serum obtained from CRF or CTL rats or with PTH. Significant downregulations (≥40%) of CYP1A, CYP2C11, and CYP3A proteins were observed in microsomes from CRF rat brains. CYP3A activity reduction was also observed. CYP3A expression and activity were unaffected in PTX-pretreated CRF rats. Serum of PTX-treated CRF rats had no impact on CYP3A levels in astrocytes compared with that of untreated CRF rats. Finally, PTH addition to normal calf serum induced a reduction in CYP3A protein similar to CRF serum, suggesting that CRF-induced hyperparathyroidism is associated with a significant decrease in P450 drug-metabolizing enzymes in the brain, which may have implications in drug response. PMID:27271372

  4. MRI Reveals Edema in Larynx (But Not in Brain) During Anaphylactic Hypotension in Anesthetized Rats

    PubMed Central

    Toyota, Ichiro; Tanida, Mamoru; Wang, Mofei; Kurata, Yasutaka; Tonami, Hisao

    2013-01-01

    Purpose Anaphylactic shock is sometimes accompanied by local interstitial edema due to increased vascular permeability. We performed magnetic resonance imaging (MRI) to compare edema in the larynx and brain of anesthetized rats during anaphylactic hypotension versus vasodilator-induced hypotension. Methods Male Sprague Dawley rats were subjected to hypotension induced by the ovalbumin antigen (n=7) or a vasodilator sodium nitroprusside (SNP; n=7). Apparent diffusion coefficient (ADC) and T2-relaxation time (T2RT) were quantified on MRI performed repeatedly for up to 68 min after the injection of either agent. The presence of laryngeal edema was also examined by histological examination. Separately, the occurrence of brain edema was assessed by measuring brain water content using the wet/dry method in rats with anaphylaxis (n=5) or SNP (n=5) and the non-hypotensive control rats (n=5). Mast cells in hypothalamus were morphologically examined. Results Mean arterial blood pressure similarly decreased to 35 mmHg after an injection of the antigen or SNP. Hyperintensity on T2-weighted images (as reflected by elevated T2RT) was found in the larynx as early as 13 min after an injection of the antigen, but not SNP. A postmortem histological examination revealed epiglottic edema in the rats with anaphylaxis, but not SNP. In contrast, no significant changes in T2RT or ADC were detectable in the brains of any rats studied. In separate experiments, the quantified brain water content did not increase in either anaphylaxis or SNP rats, as compared with the non-hypotensive control rats. The numbers of mast cells with metachromatic granules in the hypothalamus were not different between rats with anaphylaxis and SNP, suggesting the absence of anaphylactic reaction in hypothalamus. Conclusion Edema was detected using the MRI technique in the larynx during rat anaphylaxis, but not in the brain. PMID:24179686

  5. Cloning and expression of an A1 adenosine receptor from rat brain

    SciTech Connect

    Mahan, L.C.; McVittie, L.D.; Smyk-Randall, E.M.; Nakata, H.; Monsma, F.J. Jr.; Gerfen, C.R.; Sibley, D.R. )

    1991-07-01

    The authors have used the polymerase chain reaction technique to selectively amplify guanine nucleotide-binding regulatory protein (G protein)-coupled receptor cDNA sequences from rat striatal mRNA, using sets of highly degenerate primers derived from transmembrane sequences of previously cloned G protein-coupled receptors. A novel cDNA fragment was identified, which exhibits considerable homology to various members of the G protein-coupled receptor family. This fragment was used to isolate a full-length cDNA from a rat striatal library. A 2.2-kilobase clone was obtained that encodes a protein of 326 amino acids with seven transmembrane domains, as predicted by hydropathy analysis. Stably transfected mouse A9-L cells and Chinese hamster ovary cells that expressed mRNA for this clone were screened with putative receptor ligands. Saturable and specific binding sites for the A1 adenosine antagonist (3H)-1,3-dipropyl-8-cyclopentylxanthine were identified on membranes from transfected cells. The rank order of potency and affinities of various adenosine agonist and antagonist ligands confirmed the identity of this cDNA clone as an A1 adenosine receptor. The high affinity binding of A1 adenosine agonists was shown to be sensitive to the nonhydrolyzable GTP analog guanylyl-5{prime}-imidodiphosphate. In adenylyl cyclase assays, adenosine agonists inhibited forskolin-stimulated cAMP production by greater than 50%, in a pharmacologically specific fashion. Northern blot and in situ hybridization analyses of receptor mRNA in brain tissues revealed two transcripts of 5.6 and 3.1 kilobases, both of which were abundant in cortex, cerebellum, hippocampus, and thalamus, with lower levels in olfactory bulb, striatum, mesencephalon, and retina. These regional distribution data are in good agreement with previous receptor autoradiographic studies involving the A1 adenosine receptor.

  6. Effect of MCI-186 on ischemia-induced changes in monoamine metabolism in rat brain.

    PubMed

    Oishi, R; Itoh, Y; Nishibori, M; Watanabe, T; Nishi, H; Saeki, K

    1989-11-01

    We examined the effects of MCI-186 (3-methyl-1-phenyl-2-pyrazolin-5-one), a novel free radical scavenger and an inhibitor of ischemia-induced brain edema, on monoamine metabolism in the brains of both normal and ischemic rats. In normal rats, 3 mg/kg i.v. MCI-186, a dose that prevents ischemic brain edema, had no significant effect on brain concentrations of dopamine, norepinephrine, 5-hydroxytryptamine, or their metabolites. After the injection of 5 microliters of 3% polyvinyl acetate into the left internal carotid artery, concentrations of 3,4-dihydroxyphenylacetic acid and homovanillic acid markedly increased, but that of norepinephrine decreased, in the left telencephalon of embolized rats compared with control rats injected with vehicle; the concentration of 5-hydroxyindoleacetic acid also increased slightly. These effects were maximal 2 hours after embolization. The turnover rate of dopamine between 6 and 8 hours after embolization was significantly higher but that of norepinephrine was slightly lower than that in vehicle-treated rats. When rats were treated with 3 mg/kg i.v. MCI-186 immediately after the injection of polyvinyl acetate, the embolization-induced changes in monoamine metabolism were less marked. Our results suggest that MCI-186 attenuates ischemia-induced changes in brain monoamine metabolism, probably due to its free radical scavenging action, although it has no marked effect in normal rats. PMID:2815191

  7. Population-averaged diffusion tensor imaging atlas of the Sprague Dawley rat brain.

    PubMed

    Veraart, Jelle; Leergaard, Trygve B; Antonsen, Bjørnar T; Van Hecke, Wim; Blockx, Ines; Jeurissen, Ben; Jiang, Yi; Van der Linden, Annemie; Johnson, G Allan; Verhoye, Marleen; Sijbers, Jan

    2011-10-15

    Rats are widely used in experimental neurobiological research, and rat brain atlases are important resources for identifying brain regions in the context of experimental microsurgery, tissue sampling, and neuroimaging, as well as comparison of findings across experiments. Currently, most available rat brain atlases are constructed from histological material derived from single specimens, and provide two-dimensional or three-dimensional (3D) outlines of diverse brain regions and fiber tracts. Important limitations of such atlases are that they represent individual specimens, and that finer details of tissue architecture are lacking. Access to more detailed 3D brain atlases representative of a population of animals is needed. Diffusion tensor imaging (DTI) is a unique neuroimaging modality that provides sensitive information about orientation structure in tissues, and is widely applied in basic and clinical neuroscience investigations. To facilitate analysis and assignment of location in rat brain neuroimaging investigations, we have developed a population-averaged three-dimensional DTI atlas of the normal adult Sprague Dawley rat brain. The atlas is constructed from high resolution ex vivo DTI images, which were nonlinearly warped into a population-averaged in vivo brain template. The atlas currently comprises a selection of manually delineated brain regions, the caudate-putamen complex, globus pallidus, entopeduncular nucleus, substantia nigra, external capsule, corpus callosum, internal capsule, cerebral peduncle, fimbria of the hippocampus, fornix, anterior commisure, optic tract, and stria terminalis. The atlas is freely distributed and potentially useful for several purposes, including automated and manual delineation of rat brain structural and functional imaging data. PMID:21749925

  8. Ultra-high spatial resolution basal and evoked cerebral blood flow MRI of the rat brain.

    PubMed

    Shen, Qiang; Huang, Shiliang; Duong, Timothy Q

    2015-03-01

    Cerebral blood flow (CBF) is tightly coupled to metabolism and neural activity under normal physiological conditions, and is often perturbed in disease states. The goals of this study were to implement a high-resolution (up to 50×38μm(2)) CBF MRI protocol of the rat brain, create a digital CBF atlas, report CBF values for 30+ brain structures based on the atlas, and explore applications of high-resolution CBF fMRI of forepaw stimulation. Excellent blood-flow contrasts were observed among different cortical and subcortical structures. CBF MRI showed column-like alternating bright and dark bands in the neocortices, reflecting the layout of descending arterioles and ascending venules, respectively. CBF MRI also showed lamina-like alternating bright and dark layers across the cortical thicknesses, consistent with the underlying vascular density. CBF profiles across the cortical thickness showed two peaks in layers IV and VI and a shallow trough in layer V. Whole-brain CBF was about 0.89ml/g/min, with the highest CBF values found amongst the neocortical structures (1ml/g/min, range: 0.89-1.16ml/g/min) and the lowest CBF values in the corpus callosum (0.32ml/g/min), yielding a gray:white matter CBF ratio of 3.1. CBF fMRI responses peaked across layers IV-V, whereas the BOLD fMRI responses showed a peak in the superficial layers II-III. High-resolution basal CBF MRI, evoked CBF fMRI, and CBF brain atlas can be used to study neurological disorders (such as ischemic stroke). PMID:25557404

  9. Aluminum Nanoparticles Induce ERK and p38MAPK Activation in Rat Brain

    PubMed Central

    Seo, Gyun-Baek; Jo; Lee, Mimi; Shim, Ilseob; Lee, Byung-Woo; Yoon, Byung-Il; Kim, Pilje; Choi, Kyunghee

    2013-01-01

    Aluminum nanoparticles (Al-NPs) are one of the most widely used nanomaterial in cosmetics and medical materials. For this reason, Al-NP exposure is very likely to occur via inhalation in the environment and the workplace. Nevertheless, little is known about the mechanism of Al-NP neurotoxicity via inhalation exposure. In this study, we investigated the effect AL-NPs on the brain. Rats were exposed to Al-NPs by nasal instillation at 1 mg/kg body weight (low exposure group), 20 mg/kg body weight (moderate exposure group), and 40 mg/kg body weight (high exposure group), for a total of 3 times, with a 24-hr interval after each exposure. Inductively coupled plasma mass spectrometry (ICP-MS) analysis indicated that the presence of aluminum was increased in a dose-dependent manner in the olfactory bulb (OFB) and the brain. In microarray analysis, the regulation of mitogen-activated protein kinases (MAPK) activity (GO: 0043405), including Ptprc, P2rx7, Map2k4, Trib3, Trib1, and Fgd4 was significantly over-expressed in the treated mice than in the controls (p = 0.0027). Moreover, Al-NPs induced the activation of ERK1 and p38 MAPK protein expression in the brain, but did not alter the protein expression of JNK, when compared to the control. These data demonstrate that the nasal exposure of Al-NPs can permeate the brain via the olfactory bulb and modulate the gene and protein expression of MAPK and its activity. PMID:24386518

  10. Aluminum Nanoparticles Induce ERK and p38MAPK Activation in Rat Brain.

    PubMed

    Kwon, Jung-Taek; Seo, Gyun-Baek; Jo; Lee, Mimi; Kim, Hyun-Mi; Shim, Ilseob; Lee, Byung-Woo; Yoon, Byung-Il; Kim, Pilje; Choi, Kyunghee

    2013-09-01

    Aluminum nanoparticles (Al-NPs) are one of the most widely used nanomaterial in cosmetics and medical materials. For this reason, Al-NP exposure is very likely to occur via inhalation in the environment and the workplace. Nevertheless, little is known about the mechanism of Al-NP neurotoxicity via inhalation exposure. In this study, we investigated the effect AL-NPs on the brain. Rats were exposed to Al-NPs by nasal instillation at 1 mg/kg body weight (low exposure group), 20 mg/kg body weight (moderate exposure group), and 40 mg/kg body weight (high exposure group), for a total of 3 times, with a 24-hr interval after each exposure. Inductively coupled plasma mass spectrometry (ICP-MS) analysis indicated that the presence of aluminum was increased in a dose-dependent manner in the olfactory bulb (OFB) and the brain. In microarray analysis, the regulation of mitogen-activated protein kinases (MAPK) activity (GO: 0043405), including Ptprc, P2rx7, Map2k4, Trib3, Trib1, and Fgd4 was significantly over-expressed in the treated mice than in the controls (p = 0.0027). Moreover, Al-NPs induced the activation of ERK1 and p38 MAPK protein expression in the brain, but did not alter the protein expression of JNK, when compared to the control. These data demonstrate that the nasal exposure of Al-NPs can permeate the brain via the olfactory bulb and modulate the gene and protein expression of MAPK and its activity. PMID:24386518

  11. Effect of Cyclosporin A on the Uptake of D3-Selective PET Radiotracers in Rat Brain

    PubMed Central

    Tu, Zhude; Li, Shihong; Xu, Jinbin; Chu, Wenhua; Jones, Lynne A.; Luedtke, Robert R.; Mach, Robert H.

    2011-01-01

    Introduction Four benzamide analogs having a high affinity and selectivity for D3 versus D2 receptors were radiolabeled with 11C or 18F for in vivo evaluation. Methods Precursors were synthesized and the four D3 selective benzamide analogs were radiolabeled. The tissue distribution and brain uptake of the four compounds were evaluated in control rats and rats pretreated with cyclosporin A, a modulator of P-glycoprotein and an inhibitor of other ABC efflux transporters that contribute to the blood brain barrier. MicroPET imaging was carried out for [11C]6 in a control and a cyclosporin A pre-treated rat. Results All four compounds showed low brain uptake in control rats at 5 and 30 min post-injection; despite recently reported rat behavioral studies conducted on analogs 6 (WC-10) and 7 (WC-44). Following administration of cyclosporin A, increased brain uptake was observed with all four PET radiotracers at both 5 and 30 min post-i.v. injection. An increase in brain uptake following modulation/inhibition of the ABC transporters was also observed in the microPET study. Conclusions These data suggest that D3 selective conformationally-flexible benzamide analogs which contain a N-2-methoxyphenylpiperazine moiety are substrates for P-glycoprotein or other ABC transporters expressed at the blood-brain barrier, and that PET radiotracers containing this pharmacophore may display low brain uptake in rodents due to the action of these efflux transporters. PMID:21718948

  12. Rat brain endothelial cells are a target of manganese toxicity

    PubMed Central

    Marreilha dos Santos, Ana Paula; Milatovic, Dejan; Au, Catherine; Yin, Zhaobao; Batoreu, Maria Camila C.; Aschner, Michael

    2010-01-01

    Manganese (Mn) is an essential trace metal, however exposure to high Mn levels can result in neurodegenerative changes resembling Parkinson´s disease (PD). Information on Mn´s effects on endothelial cells of the blood-brain barrier (BBB) is lacking. Accordingly, we tested the hypothesis that BBB endothelial cells are a primary target for Mn-induced neurotoxicity. The studies were conducted in an in vitro BBB model of immortalized rat brain endothelial (RBE4) cells. ROS production was determined by F2-Isoprostane (F2-IsoPs) measurement. The relationship between Mn toxicity and redox status was investigated upon intracellular glutathione (GSH) depletion with diethylmaleate (DEM) or L-buthionine sulfoximine (BSO). Mn exposure (200 or 800 µM MnCl2 or MnSO4) for 4 or 24h led to significant decrease in cell viability vs. controls. DEM or BSO pre-treatment led to further enhancement in cytotoxicity vs. exposure to Mn alone, with more pronounced cell death after 24h DEM pre-treatment. F2-IsoPs levels in cells exposed to MnCl2 (200 or 800 µM), were significantly increased after 4h and remained elevated 24h after exposure compared with controls. Consistent with the effects on cell viability and F2-IsoPs, treatment with MnCl2 (200 or 800 µM) was also associated with a significant decrease in membrane potential. This effect was more pronounced in cells exposed to DEM plus MnCl2 vs. cells exposed to Mn alone. We conclude that Mn induces direct injury to mitochondria in RBE4 cells. The ensuing impairment in energy metabolism and redox status may modify the restrictive properties of the BBB compromising its function. PMID:20170646

  13. Toward dynamic isotopomer analysis in the rat brain in vivo: automatic quantitation of 13C NMR spectra using LCModel.

    PubMed

    Henry, Pierre-Gilles; Oz, Gülin; Provencher, Stephen; Gruetter, Rolf

    2003-01-01

    The LCModel method was adapted to analyze localized in vivo (13)C NMR spectra obtained from the rat brain in vivo at 9.4 T. Prior knowledge of chemical-shifts, J-coupling constants and J-evolution was included in the analysis. Up to 50 different isotopomer signals corresponding to 10 metabolites were quantified simultaneously in 400 microl volumes in the rat brain in vivo during infusion of [1,6-(13)C(2)]glucose. The analysis remained accurate even at low signal-to-noise ratio of the order of 3:1. The relative distribution of isotopomers in glutamate, glutamine and aspartate determined in vivo in 22 min was in excellent agreement with that measured in brain extracts. Quantitation of time series of (13)C spectra yielded time courses of total (13)C label incorporation into up to 16 carbon positions, as well as time courses of individual isotopomer signals, with a temporal resolution as low as 5 min (dynamic isotopomer analysis). The possibility of measuring in vivo a wealth of information that was hitherto accessible only in extracts is likely to expand the scope of metabolic studies in the intact brain. PMID:14679502

  14. Brain and Serum Androsterone Is Elevated in Response to Stress in Rats with Mild Traumatic Brain Injury

    PubMed Central

    Servatius, Richard J.; Marx, Christine E.; Sinha, Swamini; Avcu, Pelin; Kilts, Jason D.; Naylor, Jennifer C.; Pang, Kevin C. H.

    2016-01-01

    Exposure to lateral fluid percussion (LFP) injury consistent with mild traumatic brain injury (mTBI) persistently attenuates acoustic startle responses (ASRs) in rats. Here, we examined whether the experience of head trauma affects stress reactivity. Male Sprague-Dawley rats were matched for ASRs and randomly assigned to receive mTBI through LFP or experience a sham surgery (SHAM). ASRs were measured post injury days (PIDs) 1, 3, 7, 14, 21, and 28. To assess neurosteroids, rats received a single 2.0 mA, 0.5 s foot shock on PID 34 (S34), PID 35 (S35), on both days (2S), or the experimental context (CON). Levels of the neurosteroids pregnenolone (PREG), allopregnanolone (ALLO), and androsterone (ANDRO) were determined for the prefrontal cortex, hippocampus, and cerebellum. For 2S rats, repeated blood samples were obtained at 15, 30, and 60 min post-stressor for determination of corticosterone (CORT) levels after stress or context on PID 34. Similar to earlier work, ASRs were severely attenuated in mTBI rats without remission for 28 days after injury. No differences were observed between mTBI and SHAM rats in basal CORT, peak CORT levels or its recovery. In serum and brain, ANDRO levels were the most stress-sensitive. Stress-induced ANDRO elevations were greater than those in mTBI rats. As a positive allosteric modulator of gamma-aminobutyric acid (GABAA) receptors, increased brain ANDRO levels are expected to be anxiolytic. The impact of brain ANDRO elevations in the aftermath of mTBI on coping warrants further elaboration. PMID:27616978

  15. Does bosentan protect diabetic brain alterations in rats? The role of endothelin-1 in the diabetic brain.

    PubMed

    Demir, Recep; Cadirci, Elif; Akpinar, Erol; Cayir, Yasemin; Atmaca, Hasan Tarik; Un, Harun; Kunak, Celalettin Semih; Yayla, Muhammed; Bayraktutan, Zafer; Demir, Ilknur

    2015-03-01

    Diabetes mellitus (DM) is a major problem all over the world, affecting more people in recent years. Individuals with diabetes are more prone to disease than non-diabetics, especially vascular complications. The aim of this study was to examine the roles of the endothelin (ET)-1 in brain damage formed in a streptozocin (STZ)-induced diabetes model, and the effect of bosentan, which is the non-specific ET1 receptor blocker in the prevention of the diabetes-induced brain damage. To examine the effects of bosentan (50 mg/kg and 100 mg/kg) in this study, the rats were given the drug for 3 months. The rats were divided into four groups: the sham group (n = 10), the diabetic control group (n = 10), the group of diabetic rats given bosentan 50 mg/kg (n = 10) and the group of diabetic rats given bosentan 100 mg/kg (n = 10). Diabetes was induced in the rats by STZ (60 mg/kg i.p.). On day 91, all rats were killed. Brain tissues of the rats were measured by molecular, biochemical and histopathological methods. Antioxidant levels in the therapy groups were observed as quite near to the values in the healthy group. In this study, while the brain eNOS levels in the diabetic groups decreased, the ET1 and iNOS levels were found to be increased. However, in the diabetes group, hippocampus and cerebellum, pericellular oedema and a number of neuronal cytoretraction were increased in neuropiles, whereas these results were decreased in the therapy group. Based on all of these results, ET1 will not be ignored in diabetes-induced cerebral complications. PMID:25200216

  16. Brain and Serum Androsterone Is Elevated in Response to Stress in Rats with Mild Traumatic Brain Injury.

    PubMed

    Servatius, Richard J; Marx, Christine E; Sinha, Swamini; Avcu, Pelin; Kilts, Jason D; Naylor, Jennifer C; Pang, Kevin C H

    2016-01-01

    Exposure to lateral fluid percussion (LFP) injury consistent with mild traumatic brain injury (mTBI) persistently attenuates acoustic startle responses (ASRs) in rats. Here, we examined whether the experience of head trauma affects stress reactivity. Male Sprague-Dawley rats were matched for ASRs and randomly assigned to receive mTBI through LFP or experience a sham surgery (SHAM). ASRs were measured post injury days (PIDs) 1, 3, 7, 14, 21, and 28. To assess neurosteroids, rats received a single 2.0 mA, 0.5 s foot shock on PID 34 (S34), PID 35 (S35), on both days (2S), or the experimental context (CON). Levels of the neurosteroids pregnenolone (PREG), allopregnanolone (ALLO), and androsterone (ANDRO) were determined for the prefrontal cortex, hippocampus, and cerebellum. For 2S rats, repeated blood samples were obtained at 15, 30, and 60 min post-stressor for determination of corticosterone (CORT) levels after stress or context on PID 34. Similar to earlier work, ASRs were severely attenuated in mTBI rats without remission for 28 days after injury. No differences were observed between mTBI and SHAM rats in basal CORT, peak CORT levels or its recovery. In serum and brain, ANDRO levels were the most stress-sensitive. Stress-induced ANDRO elevations were greater than those in mTBI rats. As a positive allosteric modulator of gamma-aminobutyric acid (GABAA) receptors, increased brain ANDRO levels are expected to be anxiolytic. The impact of brain ANDRO elevations in the aftermath of mTBI on coping warrants further elaboration. PMID:27616978

  17. Neural stem cell protects aged rat brain from ischemia–reperfusion injury through neurogenesis and angiogenesis

    PubMed Central

    Tang, Yaohui; Wang, Jixian; Lin, Xiaojie; Wang, Liuqing; Shao, Bei; Jin, Kunlin; Wang, Yongting; Yang, Guo-Yuan

    2014-01-01

    Neural stem cells (NSCs) show therapeutic potential for ischemia in young-adult animals. However, the effect of aging on NSC therapy is largely unknown. In this work, NSCs were transplanted into aged (24-month-old) and young-adult (3-month-old) rats at 1 day after stroke. Infarct volume and neurobehavioral outcomes were examined. The number of differentiated NSCs was compared in aged and young-adult ischemic rats and angiogenesis and neurogenesis were also determined. We found that aged rats developed larger infarcts than young-adult rats after ischemia (P<0.05). The neurobehavioral outcome was also worse for aged rats comparing with young-adult rats. Brain infarction and neurologic deficits were attenuated after NSC transplantation in both aged and young-adult rats. The number of survived NSCs in aged rats was similar to that of the young-adult rats (P>0.05) and most of them were differentiated into glial fibrillary acidic protein+ (GFAP+) cells. More importantly, angiogenesis and neurogenesis were greatly enhanced in both aged and young-adult rats after transplantation compared with phosphate-buffered saline (PBS) control (P<0.05), accompanied by increased expression of vascular endothelial growth factor (VEGF). Our results showed that NSC therapy reduced ischemic brain injury, along with increased angiogenesis and neurogenesis in aged rats, suggesting that aging-related microenvironment does not preclude a beneficial response to NSCs transplantation during cerebral ischemia. PMID:24714034

  18. Iodine-125-labeled triiodothyronine in rat brain: evidence for localization in discrete neural systems

    SciTech Connect

    Dratman, M.B.; Futaesaku, Y.; Crutchfield, F.L.; Berman, N.; Payne, B.; Sar, M.; Stumpf, W.E.

    1982-01-15

    Autoradiograms prepared from adult rat brains demonstrate that nerve cells and neuropil in different brain regions selectively concentrate and retain intravenously administered triiodothyronine, by mechanisms susceptible to saturation with excess triiodothyronine. A neuroregulatory role for thyroid hormones, strongly supported by the observations, may account for their marked effects on behavior and the activity of the autonomic nervous system.

  19. Enhancement of Sexual Behavior in Female Rats by Neonatal Transplantation of Brain Tissue from Males

    NASA Astrophysics Data System (ADS)

    Arendash, Gary W.; Gorski, Roger A.

    1982-09-01

    Transplantation of preoptic tissue from male rat neonates into the preoptic area of female littermates increased masculine and feminine sexual behavior in the recipients during adulthood. This suggests that functional connections develop between the transplanted neural tissue and the host brain. A new intraparenchymal brain transplantation technique was used to achieve these results.

  20. Congenital Viral Infections of the Brain: Lessons Learned from Lymphocytic Choriomeningitis Virus in the Neonatal Rat

    PubMed Central

    Bonthius, Daniel J; Perlman, Stanley

    2007-01-01

    The fetal brain is highly vulnerable to teratogens, including many infectious agents. As a consequence of prenatal infection, many children suffer severe and permanent brain injury and dysfunction. Because most animal models of congenital brain infection do not strongly mirror human disease, the models are highly limited in their abilities to shed light on the pathogenesis of these diseases. The animal model for congenital lymphocytic choriomeningitis virus (LCMV) infection, however, does not suffer from this limitation. LCMV is a well-known human pathogen. When the infection occurs during pregnancy, the virus can infect the fetus, and the developing brain is particularly vulnerable. Children with congenital LCMV infection often have substantial neurological deficits. The neonatal rat inoculated with LCMV is a superb model system of human congenital LCMV infection. Virtually all of the neuropathologic changes observed in humans congenitally infected with LCMV, including microencephaly, encephalomalacia, chorioretinitis, porencephalic cysts, neuronal migration disturbances, periventricular infection, and cerebellar hypoplasia, are reproduced in the rat model. Within the developing rat brain, LCMV selectively targets mitotically active neuronal precursors. Thus, the targets of infection and sites of pathology depend on host age at the time of infection. The rat model has further shown that the pathogenic changes induced by LCMV infection are both virus-mediated and immune-mediated. Furthermore, different brain regions simultaneously infected with LCMV can undergo widely different pathologic changes, reflecting different brain region–virus–immune system interactions. Because the neonatal rat inoculated with LCMV so faithfully reproduces the diverse neuropathology observed in the human counterpart, the rat model system is a highly valuable tool for the study of congenital LCMV infection and of all prenatal brain infections In addition, because LCMV induces delayed

  1. High-strain-rate brain injury model using submerged acute rat brain tissue slices.

    PubMed

    Sarntinoranont, Malisa; Lee, Sung J; Hong, Yu; King, Michael A; Subhash, Ghatu; Kwon, Jiwoon; Moore, David F

    2012-01-20

    Blast-induced traumatic brain injury (bTBI) has received increasing attention in recent years due to ongoing military operations in Iraq and Afghanistan. Sudden impacts or explosive blasts generate stress and pressure waves that propagate at high velocities and affect sensitive neurological tissues. The immediate soft tissue response to these stress waves is difficult to assess using current in vivo imaging technologies. However, these stress waves and resultant stretching and shearing of tissue within the nano- to microsecond time scale of blast and impact are likely to cause initial injury. To visualize the effects of stress wave loading, we have developed a new ex vivo model in which living tissue slices from rat brain, attached to a ballistic gelatin substrate, were subjected to high-strain-rate loads using a polymer split Hopkinson pressure bar (PSHPB) with real-time high-speed imaging. In this study, average peak fluid pressure within the test chamber reached a value of 1584±63.3 psi. Cavitation due to a trailing underpressure wave was also observed. Time-resolved images of tissue deformation were collected and large maximum eigenstrains (0.03-0.42), minimum eigenstrains (-0.33 to -0.03), maximum shear strains (0.09-0.45), and strain rates (8.4×10³/sec) were estimated using digital image correlation (DIC). Injury at 4 and 6 h was quantified using Fluoro-Jade C. Neuronal injury due to PSHPB testing was found to be significantly greater than injury associated with the tissue slice paradigm alone. While large pressures and strains were encountered for these tests, this system provides a controllable test environment to study injury to submerged brain slices over a range of strain rate, pressure, and strain loads. PMID:21970544

  2. Felbamate increases [3H]glycine binding in rat brain and sections of human postmortem brain.

    PubMed

    McCabe, R T; Sofia, R D; Layer, R T; Leiner, K A; Faull, R L; Narang, N; Wamsley, J K

    1998-08-01

    The anticonvulsant compound felbamate (2-phenyl-1,3-propanediol dicarbamate; FBM) appears to inhibit the function of the N-methyl-D-aspartate (NMDA) receptor complex through an interaction with the strychnine-insensitive glycine recognition site. Since we have demonstrated previously that FBM inhibits the binding of [3H]5, 7-dichlorokynurenic acid (DCKA), a competitive antagonist at the glycine site, we assessed the ability of FBM to modulate the binding of an agonist, [3H]glycine, to rat forebrain membranes and human brain sections. In contrast to its ability to inhibit [3H]5,7-DCKA binding, FBM increased [3H]glycine binding (20 nM; EC50 = 485 microM; Emax = 211% of control; nH = 1.8). FBM, but not carbamazepine, phenytoin, valproic acid or phenobarbital, also increased [3H]glycine binding (50 nM; EC50 = 142 microM; Emax = 157% of control; nH = 1.6) in human cortex sections. Autoradiographic analysis of human brain slices demonstrated that FBM produced the largest increases in [3H]glycine binding in the cortex, hippocampus and the parahippocampal gyrus. Because various ions can influence the binding of glycine-site ligands, we assessed their effects on FBM-modulation of [3H]glycine binding. FBM-enhanced [3H]glycine binding was attenuated by Zn++ and not inhibited by Mg++ in human brain. These results suggest that FBM increases [3H]glycine binding in a manner sensitive to ions which modulate the NMDA receptor. These data support the hypothesis that FBM produces anticonvulsant and neuroprotective effects by inhibiting NMDA receptor function, likely through an allosteric modulation of the glycine site. PMID:9694960

  3. In vivo deep brain imaging of rats using oral-cavity illuminated photoacoustic computed tomography

    NASA Astrophysics Data System (ADS)

    Lin, Li; Xia, Jun; Wong, Terence T. W.; Li, Lei; Wang, Lihong V.

    2015-01-01

    Using internal illumination with an optical fiber in the oral cavity, we demonstrate, for the first time, photoacoustic computed tomography (PACT) of the deep brain of rats in vivo. The experiment was performed on a full-ring-array PACT system, with the capability of providing high-speed cross-sectional imaging of the brain. Compared with external illumination through the cranial skull, internal illumination delivers more light to the base of the brain. Consequently, in vivo photoacoustic images clearly reveal deep brain structures such as the hypothalamus, brain stem, and cerebral medulla.

  4. In vivo acylation of rat brain myelin proteolipid protein.

    PubMed

    Agrawal, H C; Randle, C L; Agrawal, D

    1982-04-25

    Examination of brain myelin proteins by sodium dodecyl sulfate-gel electrophoresis followed by fluorography clearly showed that both proteolipid protein (PLP) and DM-20 were acylated 24 h after the intracerebral injection of 30-day-old rats with [3H]palmitic acid. The radioactivity associated with PLP remained after purification, re-electrophoresis, and fluorography. Most of the radioactivity associated with PLP was removed when the gels were treated with hydroxylamine and then fluorographed, indicating that fatty acids were bound to PLP by ester linkage. Cleavage of purified PLP with methanolic sodium hydroxide readily released almost all protein-bound radioactivity. Thin layer chromatography of this material on both silver nitrate and reverse-phase plates provided evidence that most of the radioactivity co-migrated with methyl palmitate (77%) and methyl stearate (19%); however, some radioactivity was associated with methyl oleate (4%). Gas-liquid chromatography of the fatty acids associated with PLP distinctly revealed the presence of methyl palmitate and a detectable peak of methyl stearate. PMID:7068653

  5. Brain stimulation in rats exposed to hyperbaric environments.

    PubMed

    Ackerman, M J; Spencer, J W

    1976-12-01

    Six rats were trained to make an operant response to receive brief trains of electrical current to the lateral hypothalamus (self-stimulation). All animals were then randomly exposed to pressures of 4.03, 5.51, 7.06, or 10.1 ATA breathing either compressed air or N2-O2 and 13.1 ATA (N2-O2 only). When the subjects breathed air at pressures of 7.06 and 10.1 ATA, rate of self-stimulation decreased by 32 and 43%, respectively. No differences were observed in rate of response at any pressure when the animals breathed N2-O2 with the partial pressure of oxygen maintained at 0.2 ATA. When an oxygen-nitrogen mixture was breathed at 3 ATA in which the PO2 was similar to compressed air at 10.1 ATA, self-stimulation rate was decreased by 40%; this suggests that PO2 is a critical variable influencing behavior mediated by brain stimulation. Results are discussed in terms of the use of self-stimulation as one tool for better understanding the neuronal mechanisms of behavior as they relate to breathing-gas mixtures at increased pressures. PMID:10897863

  6. (/sup 3/H)-beta-endorphin binding in rat brain

    SciTech Connect

    Houghten, R.A.; Johnson, N.; Pasternak, G.W.

    1984-10-01

    The binding of (/sup 3/H)-beta-endorphin to rat brain homogenates is complex. Although Scatchard analysis of saturation studies yields a straight line, detailed competition studies are multiphasic, suggesting that even at low concentrations of the compound, the /sup 3/H-ligand is binding to more than one class of site. A portion of (/sup 3/H)-beta-endorphin binding is sensitive to low concentrations of morphine or D-Ala2-Leu5-enkephalin (less than 5 nM). The inhibition observed with each compound alone (5 nM) is the same as that seen with both together (each at 5 nM). Thus, the binding remaining in the presence of both morphine and the enkephalin does not correspond to either mu or delta sites. The portion of (/sup 3/H)-beta-endorphin binding that is inhibited under these conditions appears to be equally sensitive to both morphine and the enkephalin and may correspond to mu1 sites. Treating membrane homogenates with naloxonazine, a mu1 selective antagonist, lowers (/sup 3/H)-beta-endorphin binding to the same degree as morphine and D-Ala2-Leu5-enkephalin alone or together. This possible binding of (/sup 3/H)-beta-endorphin to mu1 sites is consistent with the role of mu1 sites in beta-endorphin analgesia and catalepsy in vivo.

  7. Localization of a brain sulfotransferase, SULT4A1, in the human and rat brain: an immunohistochemical study.

    PubMed

    Liyou, Nancy E; Buller, Kathryn M; Tresillian, Michael J; Elvin, Christopher M; Scott, Heather L; Dodd, Peter R; Tannenberg, Anthony E G; McManus, Michael E

    2003-12-01

    Cytosolic sulfotransferases are believed to play a role in the neuromodulation of certain neurotransmitters and drugs. To date, four cytosolic sulfotransferases have been shown to be expressed in human brain. Recently, a novel human brain sulfotransferase has been identified and characterized, although its role and localization in the brain are unknown. Here we present the first immunohistochemical (IHC) localization of SULT4A1 in human brain using an affinity-purified polyclonal antibody raised against recombinant human SULT4A1. These results are supported and supplemented by the IHC localization of SULT4A1 in rat brain. In both human and rat brains, strong reactivity was found in several brain regions, including cerebral cortex, cerebellum, pituitary, and brainstem. Specific signal was entirely absent on sections for which preimmune serum from the corresponding animal, processed in the same way as the postimmune serum, was used in the primary screen. The findings from this study may assist in determining the physiological role of this SULT isoform. PMID:14623933

  8. Effects of nanoparticle zinc oxide on emotional behavior and trace elements homeostasis in rat brain.

    PubMed

    Amara, Salem; Slama, Imen Ben; Omri, Karim; El Ghoul, Jaber; El Mir, Lassaad; Rhouma, Khemais Ben; Abdelmelek, Hafedh; Sakly, Mohsen

    2015-12-01

    Over recent years, nanotoxicology and the potential effects on human body have grown in significance, the potential influences of nanosized materials on the central nervous system have received more attention. The aim of this study was to determine whether zinc oxide (ZnO) nanoparticles (NPs) exposure cause alterations in emotional behavior and trace elements homeostasis in rat brain. Rats were treated by intraperitoneal injection of ZnO NPs (20-30 nm) at a dose of 25 mg/kg body weight. Sub -: acute ZnO NPs treatment induced no significant increase in the zinc content in the homogenate brain. Statistically significant decreases in iron and calcium concentrations were found in rat brain tissue compared to control. However, sodium and potassium contents remained unchanged. Also, there were no significant changes in the body weight and the coefficient of brain. In the present study, the anxiety-related behavior was evaluated using the plus-maze test. ZnO NPs treatment modulates slightly the exploratory behaviors of rats. However, no significant differences were observed in the anxious index between ZnO NP-treated rats and the control group (p > 0.05). Interestingly, our results demonstrated minimal effects of ZnO NPs on emotional behavior of animals, but there was a possible alteration in trace elements homeostasis in rat brain. PMID:23744884

  9. Effect of Carr-Purcell refocusing pulse trains on transverse relaxation times of metabolites in rat brain at 9.4 T

    PubMed Central

    Deelchand, Dinesh Kumar; Henry, Pierre-Gilles; Marjańska, Małgorzata

    2014-01-01

    Purpose To investigate the effect of Carr-Purcell (CP) pulse trains on transverse relaxation times, T2, of tissue water and metabolites (both non-coupled and J-coupled spins) in the rat brain at 9.4 T using LASER, CP-LASER and T2ρ-LASER sequences. Methods Proton NMR spectra were measured in rat brain in vivo at 9.4 T. Spectra were acquired at multiple echo times ranging from 18 to 402 ms. All spectra were analyzed using LCModel with simulated basis sets. Signals of metabolites as a function of echo time were fitted using a mono-exponential function to determine their T2 relaxation times. Results Measured T2s for tissue water and all metabolites were significantly longer with CP-LASER and T2ρ-LASER compared to LASER. The T2 increased by a factor of ~1.3 for non-coupled and weakly coupled spins (e.g., N-acetylaspartate and total creatine) and by a factor of ~2 (e.g., glutamine and taurine) to ~4 (e.g., glutamate and myo-inositol) for strongly coupled spins. Conclusion Application of a CP pulse train results in a larger increase in T2 relaxation times for strongly coupled spins than for non-coupled (singlet) and weakly coupled spins. This needs to be taken into account when correcting for T2 relaxation in CP-like sequences such as LASER. PMID:24436256

  10. Age and sex-related changes in rat brain mitochondrial function.

    PubMed

    Guevara, Rocío; Gianotti, Magdalena; Roca, Pilar; Oliver, Jordi

    2011-01-01

    Aging is responsible for the decline in the function of mitochondria and their increase in size and number--adaptive mechanism to restore mitochondrial function. Estrogens increase mitochondrial function, especially in female rats. The aim of this study was to determine the age-related changes in rat brain mitochondrial function focusing on sex differences. Cellular and mitochondrial protein and DNA content, mitochondrial oxidative and phosphorylative function in male and female rat brain from four different age groups (6, 12, 18 and 24 months old) were analyzed. Mitochondria protein/DNA content decreased with aging shifting toward lesser mitochondrial functional capacity and the mitochondria number increased. A sex dimorphism was determined, with female rat brain showing mitochondria with greater functional capacity than males. These sex differences gradually increased during aging. PMID:21471708

  11. Carnosine pretreatment protects against hypoxia-ischemia brain damage in the neonatal rat model.

    PubMed

    Zhang, Xiangmin; Song, Lili; Cheng, Xiuyong; Yang, Yi; Luan, Bin; Jia, Liting; Xu, Falin; Zhang, Zhan

    2011-09-30

    Perinatal hypoxia-ischemia brain injury is a major cause of mortality and morbidity in neonates and lacks an effective treatment thus far. Carnosine has been demonstrated to play a neuroprotective role in the adult brain injuries. However, there is no information available concerning its neuroprotective role in the immature brains after hypoxia-ischemia insults. Therefore, we investigated whether carnosine could also confer neuroprotective effects in a neonatal rat hypoxia-ischemia model. Hypoxia-ischemia was induced in rats on postnatal day 7 (P7). Carnosine (250 mg/kg) was administered intraperitoneally, 30 min prior to hypoxia-ischemia induction. Morphological brain injury and biochemical markers of apoptosis and oxidative stress were evaluated 24 h after hypoxia-ischemia induction. Cognitive performance was evaluated by the Morris Water Maze test on P28-P33. We found that pretreatment with carnosine significantly reduced the infarct volume and the number of terminal-deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL)-positive cells in the hypoxia-ischemia brain. Carnosine also inhibited mRNA expression of apoptosis-inducing factor(AIF) and caspase-3, which was accompanied by an increase in superoxide dismutase(SOD)activity and a decrease in the malondialdehyde(MDA)level in carnosine-treated rats. Furthermore, carnosine also improved the spatial learning and memory abilities of rats declined due to hypoxia-ischemia. These results demonstrate that carnosine can protect rats against hypoxia-ischemia-induced brain damage by antioxidation. PMID:21693116

  12. Postischemic hyperthermia induced caspase-3 activation in the newborn rat brain after hypoxia-ischemia and exacerbated the brain damage.

    PubMed

    Fukuda, Hirotsugu; Tomimatsu, Takuji; Kanagawa, Takeshi; Mu, Junwu; Kohzuki, Masatomo; Shimoya, Koichiro; Hosono, Takayoshi; Kanzaki, Toru; Murata, Yuji

    2003-01-01

    The effects of postischemic hyperthermia were investigated in the newborn rat brain after hypoxia-ischemia (HI). Seven-day-old rats were subjected to left carotid artery ligation followed by 8% oxygen for 30 min, and divided into a hyperthermia group (rectal temperature at 39 degrees C for 6 h) and a normothermia group. Hyperthermia resulted in an approximately 5-fold increase in activated caspase-3 24 h after HI when compared with the normothermia group, and gross loss of brain tissue was observed only in the hyperthermia group at 7 and 30 days after HI. Our results show that postischemic hyperthermia exacerbates HI injury in immature brains, and that the mechanism is strongly associated with activation of an apoptotic pathway. PMID:12907852

  13. Lithium Visibility in Rat Brain and Muscle in Vivoby 7Li NMR Imaging

    NASA Astrophysics Data System (ADS)

    Komoroski, Richard A.; Pearce, John M.; Newton, Joseph E. O.

    1998-07-01

    The apparent concentration of lithium (Li)in vivowas determined for several regions in the brain and muscle of rats by7Li NMR imaging at 4.7 T with inclusion of an external standard of known concentration and visibility. The average apparent concentrations were 10.1 mM for muscle, and 4.2-5.3 mM for various brain regions under the dosing conditions used. The results were compared to concentrations determinedin vitroby high-resolution7Li NMR spectroscopy of extracts of brain and muscle tissue from the same rats. The comparison provided estimates of the7Li NMR visibility of the Li cation in each tissue region. Although there was considerable scatter of the calculated visibilities among the five rats studied, the results suggested essentially full visibility (96%) for Li in muscle, and somewhat reduced visibility (74-93%) in the various brain regions.

  14. Regional Volume Decreases in the Brain of Pax6 Heterozygous Mutant Rats: MRI Deformation-Based Morphometry

    PubMed Central

    Hiraoka, Kotaro; Sumiyoshi, Akira; Nonaka, Hiroi; Kikkawa, Takako; Kawashima, Ryuta; Osumi, Noriko

    2016-01-01

    Pax6 is a transcription factor that pleiotropically regulates various developmental processes in the central nervous system. In a previous study, we revealed that Pax6 heterozygous mutant (rSey2/+) adult rats exhibit abnormalities in social interaction. However, the brain malformations underlying the behavioral abnormality are unknown. To elucidate the brain malformations in rSey2/+ rats, we morphometrically analyzed brains of rSey2/+ and wild type rats using small-animal magnetic resonance imaging (MRI). Sixty 10-week-old rats underwent brain MRI (29 rSey2/+ rats and 31 wild type rats). SPM8 software was used for image preprocessing and statistical image analysis. Normalized maps of the Jacobian determinant, a parameter for the expansion and/or contraction of brain regions, were obtained for each rat. rSey2/+ rats showed significant volume decreases in various brain regions including the neocortex, corpus callosum, olfactory structures, hippocampal formation, diencephalon, and midbrain compared to wild type rats. Among brain regions, the anterior commissure showed significant interaction between genotype and sex, indicating the effect of genotype difference on the anterior commissure volume was more robust in females than in males. The rSey2/+ rats exhibited decreased volume in various gray and white matter regions of the brain, which may contribute to manifestation of abnormal social behaviors. PMID:27355350

  15. Regional Volume Decreases in the Brain of Pax6 Heterozygous Mutant Rats: MRI Deformation-Based Morphometry.

    PubMed

    Hiraoka, Kotaro; Sumiyoshi, Akira; Nonaka, Hiroi; Kikkawa, Takako; Kawashima, Ryuta; Osumi, Noriko

    2016-01-01

    Pax6 is a transcription factor that pleiotropically regulates various developmental processes in the central nervous system. In a previous study, we revealed that Pax6 heterozygous mutant (rSey2/+) adult rats exhibit abnormalities in social interaction. However, the brain malformations underlying the behavioral abnormality are unknown. To elucidate the brain malformations in rSey2/+ rats, we morphometrically analyzed brains of rSey2/+ and wild type rats using small-animal magnetic resonance imaging (MRI). Sixty 10-week-old rats underwent brain MRI (29 rSey2/+ rats and 31 wild type rats). SPM8 software was used for image preprocessing and statistical image analysis. Normalized maps of the Jacobian determinant, a parameter for the expansion and/or contraction of brain regions, were obtained for each rat. rSey2/+ rats showed significant volume decreases in various brain regions including the neocortex, corpus callosum, olfactory structures, hippocampal formation, diencephalon, and midbrain compared to wild type rats. Among brain regions, the anterior commissure showed significant interaction between genotype and sex, indicating the effect of genotype difference on the anterior commissure volume was more robust in females than in males. The rSey2/+ rats exhibited decreased volume in various gray and white matter regions of the brain, which may contribute to manifestation of abnormal social behaviors. PMID:27355350

  16. Dichloroacetate increases glucose use and decreases lactate in developing rat brain

    SciTech Connect

    Miller, A.L.; Hatch, J.P.; Prihoda, T.J. )

    1990-12-01

    Dichloroacetate (DCA) activates pyruvate dehydrogenase (PDH) by inhibiting PDH kinase. Neutralized DCA (100 mg/kg) or saline was intravenously administered to 20 to 25-day-old rats (50-75g). Fifteen minutes later a mixture of {sup 6-14}C glucose and {sup 3}H fluorodeoxyglucose (FDG) was administered intravenously and the animals were sacrificed by microwave irradiation (2450 MHz, 8.0 kW, 0.6-0.8 sec) after 2 or 5 min. Brain regional rates of glucose use and metabolite levels were determined. DCA-treated rats had increased rates of glucose use in all regions studied (cortex, thalamus, striatum, and brain stem), with an average increase of 41%. Lactate levels were lower in all regions, by an average of 35%. There were no significant changes in levels of ATP, creatine phosphate, or glycogen in any brain region. Blood levels of lactate did not differ significantly between the DCA- and the saline-treated groups. Blood glucose levels were higher in the DCA group. In rats sacrificed by freeze-blowing, DCA treatment caused lower brain levels of both lactate and pyruvate. These results cannot be explained by any systemic effect of DCA. Rather, it appears that in the immature rat, DCA treatment results in activation of brain PDH, increased metabolism of brain pyruvate and lactate, and a resulting increase in brain glycolytic rate.

  17. Involvement of Nuclear Related Factor 2 Signaling Pathway in the Brain of Obese Rats and Obesity-Resistant Rats Induced by High-Fat Diet.

    PubMed

    Ma, Wei-Wei; Ding, Bing-Jie; Wang, Li-Jing; Shao, Yi; Xiao, Rong

    2016-04-01

    We aimed to investigate the mechanism of brain damage in diet-induced obese (DIO) rats and diet-resistant (DR) rats from the viewpoint of redox state and nuclear related factor 2 (Nrf2) signaling pathway. Sprague-Dawley rats were fed with a high-fat diet for 10 weeks to obtain the DIO and DR rats. d-Galactose was injected subcutaneously through the back of the neck for 10 weeks to establish oxidative stress model rats. Then, the ratio of reduced glutathione (GSH)/oxidized glutathione (GSSG) and the level of glutathione peroxidase (GSH-Px) in serum and brain tissue were measured by using enzymatic assay kits. The levels of cholecystokinin and peptide YY in the brain tissue were detected by using enzyme-linked immunosorbent assay kits. In addition, the protein expression of Nrf2 and its downstream factors such as heme oxygenase 1, manganese superoxide dismutase, and NAD(P)H quinone oxidoreductase 1 (NQO1) in the brain tissue were measured by Western blotting. In the brain of DIO rats, the level of GSH and ratio of GSH/GSSG were lower, whereas the GSH-Px concentration was higher compared with DR rats significantly. On the other hand, the GSSG level was higher in the serum of DIO rats compared with the DR rats. The oxidative stress state in the brain of DIO rats, but not in DR rats, were observed. In addition, the protein expressions of Nrf2 and NQO1 were downregulated in the brain of DR rats compared with that in DIO rats. Our data suggest that the Nrf2/NQO1 signaling pathway and redox state were involved in the pathogenesis of the rats prone to obesity, but not the DR rats resistant to obesity. PMID:26784831

  18. New insights into coupling and uncoupling of cerebral blood flow and metabolism in the brain

    PubMed Central

    Venkat, Poornima; Chopp, Michael; Chen, Jieli

    2016-01-01

    The brain has high metabolic and energy needs and requires continuous cerebral blood flow (CBF), which is facilitated by a tight coupling between neuronal activity, CBF, and metabolism. Upon neuronal activation, there is an increase in energy demand, which is then met by a hemodynamic response that increases CBF. Such regional CBF increase in response to neuronal activation is observed using neuroimaging techniques such as functional magnetic resonance imaging and positron emission tomography. The mechanisms and mediators (eg, nitric oxide, astrocytes, and ion channels) that regulate CBF-metabolism coupling have been extensively studied. The neurovascular unit is a conceptual model encompassing the anatomical and metabolic interactions between the neurons, vascular components, and glial cells in the brain. It is compromised under disease states such as stroke, diabetes, hypertension, dementias, and with aging, all of which trigger a cascade of inflammatory responses that exacerbate brain damage. Hence, tight regulation and maintenance of neurovascular coupling is central for brain homeostasis. This review article also discusses the waste clearance pathways in the brain such as the glymphatic system. The glymphatic system is a functional waste clearance pathway that removes metabolic wastes and neurotoxins from the brain along paravascular channels. Disruption of the glymphatic system burdens the brain with accumulating waste and has been reported in aging as well as several neurological diseases. PMID:27374823

  19. New insights into coupling and uncoupling of cerebral blood flow and metabolism in the brain.

    PubMed

    Venkat, Poornima; Chopp, Michael; Chen, Jieli

    2016-06-30

    The brain has high metabolic and energy needs and requires continuous cerebral blood flow (CBF), which is facilitated by a tight coupling between neuronal activity, CBF, and metabolism. Upon neuronal activation, there is an increase in energy demand, which is then met by a hemodynamic response that increases CBF. Such regional CBF increase in response to neuronal activation is observed using neuroimaging techniques such as functional magnetic resonance imaging and positron emission tomography. The mechanisms and mediators (eg, nitric oxide, astrocytes, and ion channels) that regulate CBF-metabolism coupling have been extensively studied. The neurovascular unit is a conceptual model encompassing the anatomical and metabolic interactions between the neurons, vascular components, and glial cells in the brain. It is compromised under disease states such as stroke, diabetes, hypertension, dementias, and with aging, all of which trigger a cascade of inflammatory responses that exacerbate brain damage. Hence, tight regulation and maintenance of neurovascular coupling is central for brain homeostasis. This review article also discusses the waste clearance pathways in the brain such as the glymphatic system. The glymphatic system is a functional waste clearance pathway that removes metabolic wastes and neurotoxins from the brain along paravascular channels. Disruption of the glymphatic system burdens the brain with accumulating waste and has been reported in aging as well as several neurological diseases. PMID:27374823

  20. Increased plasma levels and blunted effects of brain natriuretic peptide in rats with congestive heart failure.

    PubMed

    Hoffman, A; Grossman, E; Keiser, H R

    1991-07-01

    The hemodynamic and renal effects of brain natriuretic peptide (BNP) were studied in conscious rats with experimental congestive heart failure (CHF) produced by an aortocaval fistula. The peptide had potent hypotensive, diuretic, and natriuretic effects in control rats, all of which were abolished in CHF. Plasma levels of BNP increased time-dependently during the development of CHF, and were more than four-fold higher in sodium retaining rats than in control rats. The data suggest that BNP secretion from the atria is increased in CHF, and that resistance to BNP, in addition to the relative resistance to atrial natriuretic factor, may contribute to sodium retention in CHF. PMID:1831369

  1. A switch in G protein coupling for type 1 corticotropin-releasing factor receptors promotes excitability in epileptic brains.

    PubMed

    Narla, Chakravarthi; Scidmore, Tanner; Jeong, Jaymin; Everest, Michelle; Chidiac, Peter; Poulter, Michael O

    2016-01-01

    Anxiety and stress increase the frequency of epileptic seizures. These behavioral states induce the secretion of corticotropin-releasing factor (CRF), a 40-amino acid neuropeptide neurotransmitter that coordinates many behavioral responses to stress in the central nervous system. In the piriform cortex, which is one of the most seizurogenic regions of the brain, CRF normally dampens excitability. By contrast, CRF increased the excitability of the piriform cortex in rats subjected to kindling, a model of temporal lobe epilepsy. In nonkindled rats, CRF activates its receptor, a G protein (heterotrimeric guanosine triphosphate-binding protein)-coupled receptor, and signals through a Gαq/11-mediated pathway. After seizure induction, CRF signaling occurred through a pathway involving Gαs This change in signaling was associated with reduced abundance of regulator of G protein signaling protein type 2 (RGS2), which has been reported to inhibit Gαs-dependent signaling. RGS2 knockout mice responded to CRF in a similar manner as epileptic rats. These observations indicate that seizures produce changes in neuronal signaling that can increase seizure occurrence by converting a beneficial stress response into an epileptic trigger. PMID:27303056

  2. Lactoferrin during lactation protects the immature hypoxic-ischemic rat brain

    PubMed Central

    van de Looij, Yohan; Ginet, Vanessa; Chatagner, Alexandra; Toulotte, Audrey; Somm, Emmanuel; Hüppi, Petra S; Sizonenko, Stéphane V

    2014-01-01

    Objective Lactoferrin (Lf) is an iron-binding glycoprotein secreted in maternal milk presenting anti-inflammatory and antioxidant properties. It shows efficient absorption into the brain from nutritional source. Brain injury frequently resulting from cerebral hypoxia-ischemia (HI) has a high incidence in premature infants with ensuing neurodevelopmental disabilities. We investigated the neuroprotective effect of maternal nutritional supplementation with Lf during lactation in a rat model of preterm HI brain injury using magnetic resonance imaging (MRI), brain gene, and protein expression. Methods Moderate brain HI was induced using unilateral common carotid artery occlusion combined with hypoxia (6%, 30 min) in the postnatal day 3 (P3) rat brain (24–28 weeks human equivalent). High-field multimodal MRI techniques were used to investigate the effect of maternal Lf supplementation through lactation. Expression of cytokine coding genes (TNF-α and IL-6), the prosurvival/antiapoptotic AKT protein and caspase-3 activation were also analyzed in the acute phase after HI. Results MRI analysis demonstrated reduced cortical injury in Lf rats few hours post-HI and in long-term outcome (P25). Lf reduced HI-induced modifications of the cortical metabolism and altered white matter microstructure was recovered in Lf-supplemented rats at P25. Lf supplementation significantly decreased brain TNF-α and IL-6 gene transcription, increased phosphorylated AKT levels and reduced activation of caspase-3 at 24 h post-injury. Interpretation Lf given through lactation to rat pups with cerebral HI injury shows neuroprotective effects on brain metabolism, and cerebral gray and white matter recovery. This nutritional intervention may be of high interest for the clinical field of preterm brain neuroprotection. PMID:25574471

  3. In vivo cleavability of a disulfide-based chimeric opioid peptide in rat brain.

    PubMed

    Bickel, U; Kang, Y S; Pardridge, W M

    1995-01-01

    Brain delivery of systemically administered neuropeptide drugs may be achieved by the synthesis of chimeric peptides, wherein the peptide is coupled to transport vectors via avidin-biotin technology. The present study focuses on factors that optimize the linkage of drugs to transport vectors. The vector is the OX26 monoclonal antibody to the transferrin receptor, and the model peptide used in these studies is [Lys7]dermorphin (K7DA). The K7DA is monobiotinylated at the epsilon-amino group of the Lys7 residue with either a cleavable linker, e.g., disulfide, using NHS-SS-biotin, or a noncleavable linker, e.g., amide, using NHS-XX-biotin. Disulfide cleavage of the biotinylated derivative yields the desbiotinylated peptide, which is thiolated. Structures of the K7DA analogues were confirmed by secondary ion mass spectrometry. The biotinylated peptides were coupled to a thiol-ether conjugate of the OX26 antibody and either neutral avidin (NLA) or streptavidin. The binding constants (Ki) of the K7DA, the biotinylated K7DA (bio-XX-K7DA), the desbiotinylated K7DA, and the bio-XX-KD7A conjugated to NLA-OX26 were 0.62 +/- 0.14, 1.59 +/- 0.27, 1.24 +/- 0.24, and > 10 nM, respectively, and were determined with a mu-opioid peptide radioreceptor assay. Comparable results were obtained with in vivo tail-flick analgesia testing following intracerebroventricular (icv) injection of opioid chimeric peptides. Reversibility of pharmacologic action of thiolated peptide was demonstrated by icv naloxone administration. The cleavability of the disulfide linker in vivo in rat plasma and brain was assessed with gel filtration HPLC and internal carotid artery perfusion of labeled opioid chimeric peptides.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7599264

  4. Dipeptidyl peptidase 4 inhibitor improves brain insulin sensitivity, but fails to prevent cognitive impairment in orchiectomy obese rats.

    PubMed

    Pintana, Hiranya; Pongkan, Wanpitak; Pratchayasakul, Wasana; Chattipakorn, Nipon; Chattipakorn, Siriporn C

    2015-08-01

    It is unclear whether the dipeptidyl peptidase 4 (DPP4) inhibitor can counteract brain insulin resistance, brain mitochondrial dysfunction, impairment of hippocampal synaptic plasticity and cognitive decline in testosterone-deprived obese rats. We hypothesized that DPP4 inhibitor vildagliptin improves cognitive function in testosterone-deprived obese rats by restoring brain insulin sensitivity, brain mitochondrial function and hippocampal synaptic plasticity. Thirty male Wistar rats received either a sham-operated (S, n=6) or bilateral orchiectomy (ORX, n=24). ORX rats were divided into two groups and fed with either a normal diet (ND (NDO)) or a high-fat diet (HFO) for 12 weeks. Then, ORX rats in each dietary group were divided into two subgroups (n=6/subgroup) to receive either a vehicle or vildagliptin (3 mg/kg per day, p.o.) for 4 weeks. After treatment, cognitive function, metabolic parameters, brain insulin sensitivity, hippocampal synaptic plasticity and brain mitochondrial function were determined in each rat. We found that HFO rats exhibited peripheral and brain insulin resistance, brain mitochondrial dysfunction, impaired hippocampal synaptic plasticity and cognitive decline. NDO rats did not develop peripheral and brain insulin resistance. However, impaired hippocampal synaptic plasticity and cognitive decline occurred. Vildagliptin significantly improved peripheral insulin sensitivity, restored brain insulin sensitivity and decreased brain mitochondrial reactive oxygen species production in HFO rats. However, vildagliptin did not restore hippocampal synaptic plasticity and cognitive function in both NDO and HFO rats. These findings suggest that vildagliptin could not counteract the impairment of hippocampal synaptic plasticity and cognitive decline in testosterone-deprived subjects, despite its effects on improved peripheral and brain insulin sensitivity as well as brain mitochondrial function. PMID:26016746

  5. Lipid peroxidation in rat brain is increased by simulated weightlessness and decreased by a soy-protein diet.

    PubMed

    Chowdhury, Parimal; Soulsby, Michael

    2002-01-01

    This study tested whether or not simulated weightlessness by tail-suspension increases the levels of lipid peroxidation products in rat brain. The brain tissues of rats on a soybean diet were also assayed for lipid peroxidation products to evaluate the possible role of soy-protein as a dietary anti-oxidant. Male Sprague-Dawley rats were used. Group 1 rats were fed standard Purina rat chow ad libidum and served as controls. Group 2 rats were fed a soybean diet containing 37% soy-protein and were not tail-suspended. Group 3 rats were fed standard Purina rat chow ad libidum and were tail-suspended to induce simulated weightlessness. After 2 wk, all of the rats were killed. Each whole brain was segmented into frontal cortex, cerebellum, and brain stem. After a specific weight of each segment was excised, the residual tissues were combined and used as a whole brain sample. The samples were analyzed for lipid peroxidation products by a chromogenic assay that reacts with malondialdehyde (MDA) and 4-hydroxyalkenals (4-HNE). The mean concentrations of lipid peroxidation products (MDA plus 4-HNE) in whole brain, frontal cortex, cerebellum, and brain stem of the control rats ranged from 16 to 18 micromol/g; the corresponding means ranged from 10 to 13 micromol/g in rats fed the soybean diet, and from 22 to 26 micromol/g in the tail-suspended rats. Thus, the mean levels of lipid peroxidation products in brain tissues were decreased in the rats fed the soy diet and were increased in the rats that were tail-suspended to simulate weightlessness, when compared to those of rats fed a regular diet. PMID:12017202

  6. Pharmacokinetic and metabolic studies of busulfan in rat plasma and brain.

    PubMed

    Hassan, M; Ehrsson, H; Wallin, I; Eksborg, S

    1988-01-01

    Busulfan kinetics were studied in the rat plasma and brain after an I.P. dose of 14C-busulfan or busulfan (15 mg/kg). The distribution of busulfan to the brain was rapid and the ratio brain/plasma concentration was 0.74 during the time-course of busulfan. The elimination half-lives in plasma and brain were 3h for intact busulfan and 8h for the 14C-radioactivity. The radioactivity remaining in plasma and brain after 24h was mostly busulfan metabolites e.g. sulfolane, 3-hydroxysulfolane and tetrahydrothiophene-1-oxide as identified by gas chromatography-mass spectrometry. The protein binding to rat plasma was low (9.2 +/- 4.4%). PMID:3243326

  7. Photoacoustic imaging to detect rat brain activation after cocaine hydrochloride injection

    NASA Astrophysics Data System (ADS)

    Jo, Janggun; Yang, Xinmai

    2011-03-01

    Photoacoustic imaging (PAI) was employed to detect small animal brain activation after the administration of cocaine hydrochloride. Sprague Dawley rats were injected with different concentrations (2.5, 3.0, and 5.0 mg per kg body) of cocaine hydrochloride in saline solution through tail veins. The brain functional response to the injection was monitored by photoacoustic tomography (PAT) system with horizontal scanning of cerebral cortex of rat brain. Photoacoustic microscopy (PAM) was also used for coronal view images. The modified PAT system used multiple ultrasonic detectors to reduce the scanning time and maintain a good signal-to-noise ratio (SNR). The measured photoacoustic signal changes confirmed that cocaine hydrochloride injection excited high blood volume in brain. This result shows PAI can be used to monitor drug abuse-induced brain activation.

  8. Combined effects of prenatal inhibition of vasculogenesis and neurogenesis on rat brain development

    PubMed Central

    Fan, Q.Y.; Ramakrishna, S.; Marchi, N.; Fazio, Vincent; Hallene, Kerri; Janigro, D.

    2013-01-01

    Malformations of cortical development (MCD) are one of the most common causes of neurological disabilities including autism and epilepsy. To disrupt cortical formation, methylazoxymethanol (MAM) or thalidomide (THAL) has been used to affect neurogenesis or vasculogenesis. Although previous models of MCD have been useful, these models primarily attack a single aspect of cortical development. We hypothesized that simultaneous prenatal exposure to MAM or THAL will lead to the development of a novel and specific type of brain maldevelopment. Rats were prenatally exposed to MAM and THAL. At early postnatal days, brains displayed abnormal ventricular size and hemispheric asymmetry due to altered brain water homeostasis. The postnatal brain was also characterized by gliosis in regions of focal leakage of the blood brain barrier. These morphological abnormalities gradually disappeared at adult stages. Although the adult MAM-THAL rats showed normal cortical morphology, abnormal hippocampal connectivity and mossy fiber sprouting persisted well into adulthood. PMID:18930144

  9. Epsilon Aminocaproic Acid Pretreatment Provides Neuroprotection Following Surgically Induced Brain Injury in a Rat Model.

    PubMed

    Komanapalli, Esther S; Sherchan, Prativa; Rolland, William; Khatibi, Nikan; Martin, Robert D; Applegate, Richard L; Tang, Jiping; Zhang, John H

    2016-01-01

    Neurosurgical procedures can damage viable brain tissue unintentionally by a wide range of mechanisms. This surgically induced brain injury (SBI) can be a result of direct incision, electrocauterization, or tissue retraction. Plasmin, a serine protease that dissolves fibrin blood clots, has been shown to enhance cerebral edema and hemorrhage accumulation in the brain through disruption of the blood brain barrier. Epsilon aminocaproic acid (EAA), a recognized antifibrinolytic lysine analogue, can reduce the levels of active plasmin and, in doing so, potentially can preserve the neurovascular unit of the brain. We investigated the role of EAA as a pretreatment neuroprotective modality in a SBI rat model, hypothesizing that EAA therapy would protect brain tissue integrity, translating into preserved neurobehavioral function. Male Sprague-Dawley rats were randomly assigned to one of four groups: sham (n = 7), SBI (n = 7), SBI with low-dose EAA, 150 mg/kg (n = 7), and SBI with high-dose EAA, 450 mg/kg (n = 7). SBI was induced by partial right frontal lobe resection through a frontal craniotomy. Postoperative assessment at 24 h included neurobehavioral testing and measurement of brain water content. Results at 24 h showed both low- and high-dose EAA reduced brain water content and improved neurobehavioral function compared with the SBI groups. This suggests that EAA may be a useful pretherapeutic modality for SBI. Further studies are needed to clarify optimal therapeutic dosing and to identify mechanisms of neuroprotection in rat SBI models. PMID:26463967

  10. Delayed Postconditioning Protects against Focal Ischemic Brain Injury in Rats

    PubMed Central

    Ren, Chuancheng; Gao, Xuwen; Niu, Gang; Yan, Zhimin; Chen, Xiaoyuan; Zhao, Heng

    2008-01-01

    Background We and others have reported that rapid ischemic postconditioning, interrupting early reperfusion after stroke, reduces infarction in rats. However, its extremely short therapeutic time windows, from a few seconds to minutes after reperfusion, may hinder its clinical translation. Thus, in this study we explored if delayed postconditioning, which is conducted a few hours after reperfusion, offers protection against stroke. Methods and Results Focal ischemia was generated by 30 min occlusion of bilateral common carotid artery (CCA) combined with permanent occlusion of middle cerebral artery (MCA); delayed postconditioning was performed by repetitive, brief occlusion and release of the bilateral CCAs, or of the ipsilateral CCA alone. As a result, delayed postconditioning performed at 3h and 6h after stroke robustly reduced infarct size, with the strongest protection achieved by delayed postconditioning with 6 cycles of 15 min occlusion/15 min release of the ipsilateral CCA executed from 6h. We found that this delayed postconditioning provided long-term protection for up to two months by reducing infarction and improving outcomes of the behavioral tests; it also attenuated reduction in 2-[18F]-fluoro-2-deoxy-D-glucose (FDG)-uptake therefore improving metabolism, and reduced edema and blood brain barrier leakage. Reperfusion in ischemic stroke patients is usually achieved by tissue plasminogen activator (tPA) application, however, t-PA's side effect may worsen ischemic injury. Thus, we tested whether delayed postconditioning counteracts the exacerbating effect of t-PA. The results showed that delayed postconditioning mitigated the worsening effect of t-PA on infarction. Conclusion Delayed postconditioning reduced ischemic injury after focal ischemia, which opens a new research avenue for stroke therapy and its underlying protective mechanisms. PMID:19066627

  11. Mechanisms of blast induced brain injuries, experimental studies in rats.

    PubMed

    Risling, M; Plantman, S; Angeria, M; Rostami, E; Bellander, B-M; Kirkegaard, M; Arborelius, U; Davidsson, J

    2011-01-01

    Traumatic brain injuries (TBI) potentially induced by blast waves from detonations result in significant diagnostic problems. It may be assumed that several mechanisms contribute to the injury. This study is an attempt to characterize the presumed components of the blast induced TBI. Our experimental models include a blast tube in which an anesthetized rat can be exposed to controlled detonations of explosives that result in a pressure wave with a magnitude between 130 and 260 kPa. In this model, the animal is fixed with a metal net to avoid head acceleration forces. The second model is a controlled penetration of a 2mm thick needle. In the third model the animal is subjected to a high-speed sagittal rotation angular acceleration. Immunohistochemical labeling for amyloid precursor protein revealed signs of diffuse axonal injury (DAI) in the penetration and rotation models. Signs of punctuate inflammation were observed after focal and rotation injury. Exposure in the blast tube did not induce DAI or detectable cell death, but functional changes. Affymetrix Gene arrays showed changes in the expression in a large number of gene families including cell death, inflammation and neurotransmitters in the hippocampus after both acceleration and penetration injuries. Exposure to the primary blast wave induced limited shifts in gene expression in the hippocampus. The most interesting findings were a downregulation of genes involved in neurogenesis and synaptic transmission. These experiments indicate that rotational acceleration may be a critical factor for DAI and other acute changes after blast TBI. The further exploration of the mechanisms of blast TBI will have to include a search for long-term effects. PMID:20493951

  12. Standardized Environmental Enrichment Supports Enhanced Brain Plasticity in Healthy Rats and Prevents Cognitive Impairment in Epileptic Rats

    PubMed Central

    Kouchi, Hayet Y.; Bodennec, Jacques; Morales, Anne; Georges, Béatrice; Bonnet, Chantal; Bouvard, Sandrine; Sloviter, Robert S.; Bezin, Laurent

    2013-01-01

    Environmental enrichment of laboratory animals influences brain plasticity, stimulates neurogenesis, increases neurotrophic factor expression, and protects against the effects of brain insult. However, these positive effects are not constantly observed, probably because standardized procedures of environmental enrichment are lacking. Therefore, we engineered an enriched cage (the Marlau™ cage), which offers: (1) minimally stressful social interactions; (2) increased voluntary exercise; (3) multiple entertaining activities; (4) cognitive stimulation (maze exploration), and (5) novelty (maze configuration changed three times a week). The maze, which separates food pellet and water bottle compartments, guarantees cognitive stimulation for all animals. Compared to rats raised in groups in conventional cages, rats housed in Marlau™ cages exhibited increased cortical thickness, hippocampal neurogenesis and hippocampal levels of transcripts encoding various genes involved in tissue plasticity and remodeling. In addition, rats housed in Marlau™ cages exhibited better performances in learning and memory, decreased anxiety-associated behaviors, and better recovery of basal plasma corticosterone level after acute restraint stress. Marlau™ cages also insure inter-experiment reproducibility in spatial learning and brain gene expression assays. Finally, housing rats in Marlau™ cages after severe status epilepticus at weaning prevents the cognitive impairment observed in rats subjected to the same insult and then housed in conventional cages. By providing a standardized enriched environment for rodents during housing, the Marlau™ cage should facilitate the uniformity of environmental enrichment across laboratories. PMID:23342033

  13. Standardized environmental enrichment supports enhanced brain plasticity in healthy rats and prevents cognitive impairment in epileptic rats.

    PubMed

    Fares, Raafat P; Belmeguenai, Amor; Sanchez, Pascal E; Kouchi, Hayet Y; Bodennec, Jacques; Morales, Anne; Georges, Béatrice; Bonnet, Chantal; Bouvard, Sandrine; Sloviter, Robert S; Bezin, Laurent

    2013-01-01

    Environmental enrichment of laboratory animals influences brain plasticity, stimulates neurogenesis, increases neurotrophic factor expression, and protects against the effects of brain insult. However, these positive effects are not constantly observed, probably because standardized procedures of environmental enrichment are lacking. Therefore, we engineered an enriched cage (the Marlau™ cage), which offers: (1) minimally stressful social interactions; (2) increased voluntary exercise; (3) multiple entertaining activities; (4) cognitive stimulation (maze exploration), and (5) novelty (maze configuration changed three times a week). The maze, which separates food pellet and water bottle compartments, guarantees cognitive stimulation for all animals. Compared to rats raised in groups in conventional cages, rats housed in Marlau™ cages exhibited increased cortical thickness, hippocampal neurogenesis and hippocampal levels of transcripts encoding various genes involved in tissue plasticity and remodeling. In addition, rats housed in Marlau™ cages exhibited better performances in learning and memory, decreased anxiety-associated behaviors, and better recovery of basal plasma corticosterone level after acute restraint stress. Marlau™ cages also insure inter-experiment reproducibility in spatial learning and brain gene expression assays. Finally, housing rats in Marlau™ cages after severe status epilepticus at weaning prevents the cognitive impairment observed in rats subjected to the same insult and then housed in conventional cages. By providing a standardized enriched environment for rodents during housing, the Marlau™ cage should facilitate the uniformity of environmental enrichment across laboratories. PMID:23342033

  14. Propagation of damage in brain tissue: coupling the mechanics of oedema and oxygen delivery.

    PubMed

    Lang, Georgina E; Vella, Dominic; Waters, Sarah L; Goriely, Alain

    2015-11-01

    Brain tissue swelling, or oedema, is a dangerous consequence of traumatic brain injury and stroke. In particular, a locally swollen region can cause the injury to propagate further through the brain: swelling causes mechanical compression of the vasculature in the surrounding tissue and so can cut off that tissue's oxygen supply. We use a triphasic mathematical model to investigate this propagation, and couple tissue mechanics with oxygen delivery. Starting from a fully coupled, finite elasticity, model, we show that simplifications can be made that allow us to express the volume of the propagating region of damage analytically in terms of key parameters. Our results show that performing a craniectomy, to alleviate pressure in the brain and allow the tissue to swell outwards, reduces the propagation of damage; this finding agrees with experimental observations. PMID:25822263

  15. Cross-frequency coupling of brain oscillations in studying motivation and emotion.

    PubMed

    Schutter, Dennis J L G; Knyazev, Gennady G

    2012-03-01

    Research has shown that brain functions are realized by simultaneous oscillations in various frequency bands. In addition to examining oscillations in pre-specified bands, interactions and relations between the different frequency bandwidths is another important aspect that needs to be considered in unraveling the workings of the human brain and its functions. In this review we provide evidence that studying interdependencies between brain oscillations may be a valuable approach to study the electrophysiological processes associated with motivation and emotional states. Studies will be presented showing that amplitude-amplitude coupling between delta-alpha and delta-beta oscillations varies as a function of state anxiety and approach-avoidance-related motivation, and that changes in the association between delta-beta oscillations can be observed following successful psychotherapy. Together these studies suggest that cross-frequency coupling of brain oscillations may contribute to expanding our understanding of the neural processes underlying motivation and emotion. PMID:22448078

  16. Brain activation patterns at exhaustion in rats that differ in inherent exercise capacity.

    PubMed

    Foley, Teresa E; Brooks, Leah R; Gilligan, Lori J; Burghardt, Paul R; Koch, Lauren G; Britton, Steven L; Fleshner, Monika

    2012-01-01

    In order to further understand the genetic basis for variation in inherent (untrained) exercise capacity, we examined the brains of 32 male rats selectively bred for high or low running capacity (HCR and LCR, respectively). The aim was to characterize the activation patterns of brain regions potentially involved in differences in inherent running capacity between HCR and LCR. Using quantitative in situ hybridization techniques, we measured messenger ribonuclease (mRNA) levels of c-Fos, a marker of neuronal activation, in the brains of HCR and LCR rats after a single bout of acute treadmill running (7.5-15 minutes, 15° slope, 10 m/min) or after treadmill running to exhaustion (15-51 minutes, 15° slope, initial velocity 10 m/min). During verification of trait differences, HCR rats ran six times farther and three times longer prior to exhaustion than LCR rats. Running to exhaustion significantly increased c-Fos mRNA activation of several brain areas in HCR, but LCR failed to show significant elevations of c-Fos mRNA at exhaustion in the majority of areas examined compared to acutely run controls. Results from these studies suggest that there are differences in central c-Fos mRNA expression, and potential brain activation patterns, between HCR and LCR rats during treadmill running to exhaustion and these differences could be involved in the variation in inherent running capacity between lines. PMID:23028992

  17. Neuroanatomy-based matrix-guided trimming protocol for the rat brain.

    PubMed

    Defazio, Rossella; Criado, Ana; Zantedeschi, Valentina; Scanziani, Eugenio

    2015-02-01

    Brain trimming through defined neuroanatomical landmarks is recommended to obtain consistent sections in rat toxicity studies. In this article, we describe a matrix-guided trimming protocol that uses channels to reproduce coronal levels of anatomical landmarks. Both setup phase and validation study were performed on Han Wistar male rats (Crl:WI(Han)), 10-week-old, with bodyweight of 298 ± 29 (SD) g, using a matrix (ASI-Instruments(®), Houston, TX) fitted for brains of rats with 200 to 400 g bodyweight. In the setup phase, we identified eight channels, that is, 6, 8, 10, 12, 14, 16, 19, and 21, matching the recommended landmarks midway to the optic chiasm, frontal pole, optic chiasm, infundibulum, mamillary bodies, midbrain, middle cerebellum, and posterior cerebellum, respectively. In the validation study, we trimmed the immersion-fixed brains of 60 rats using the selected channels to determine how consistently the channels reproduced anatomical landmarks. Percentage of success (i.e., presence of expected targets for each level) ranged from 89 to 100%. Where 100% success was not achieved, it was noted that the shift in brain trimming was toward the caudal pole. In conclusion, we developed and validated a trimming protocol for the rat brain that allow comparable extensiveness, homology, and relevance of coronal sections as the landmark-guided trimming with the advantage of being quickly learned by technicians. PMID:24947989

  18. Real-time monitoring of brain tissue oxygen using a miniaturized biotelemetric device implanted in freely moving rats.

    PubMed

    Bazzu, Gianfranco; Puggioni, Giulia G M; Dedola, Sonia; Calia, Giammario; Rocchitta, Gaia; Migheli, Rossana; Desole, Maria S; Lowry, John P; O'Neill, Robert D; Serra, Pier A

    2009-03-15

    A miniaturized biotelemetric device for the amperometric detection of brain tissue oxygen is presented. The new system, derived from a previous design, has been coupled with a carbon microsensor for the real-time detection of dissolved O(2) in the striatum of freely moving rats. The implantable device consists of a single-supply sensor driver, a current-to-voltage converter, a microcontroller, and a miniaturized data transmitter. The oxygen current is converted to a digital value by means of an analog-to-digital converter integrated in a peripheral interface controller (PIC). The digital data is sent to a personal computer using a six-byte packet protocol by means of a miniaturized 434 MHz amplitude modulation (AM) transmitter. The receiver unit is connected to a personal computer (PC) via a universal serial bus. Custom developed software allows the PC to store and plot received data. The electronics were calibrated and tested in vitro under different experimental conditions and exhibited high stability, low power consumption, and good linear response in the nanoampere current range. The in vivo results confirmed previously published observations on oxygen dynamics in the striatum of freely moving rats. The system serves as a rapid and reliable model for studying the effects of different drugs on brain oxygen and brain blood flow and it is suited to work with direct-reduction sensors or O(2)-consuming biosensors. PMID:19222224

  19. Positron Spectroscopy Investigation of Normal Brain Section and Brain Section with Glioma Derived from a Rat Glioma Model

    NASA Astrophysics Data System (ADS)

    Yang, SH.; Ballmann, C.; Quarles, C. A.

    2009-03-01

    The application of positron annihilation lifetime spectroscopy (PALS) and Doppler broadening spectroscopy (DBS) to the study of animal or human tissue has only recently been reported [G. Liu, et al. phys. stat. sol. (C) 4, Nos. 10, 3912-3915 (2007)]. We have initiated a study of normal brain section and brain section with glioma derived from a rat glioma model. For the rat glioma model, 200,000 C6 cells were implanted in the basal ganglion of adult Sprague Dawley rats. The rats were sacrificed at 21 days after implantation. The brains were harvested, sliced into 2 mm thick coronal sections, and fixed in 4% formalin. PALS lifetime runs were made with the samples soaked in formalin, and there was not significant evaporation of formalin during the runs. The lifetime spectra were analyzed into two lifetime components. While early results suggested a small decrease in ortho-Positronium (o-Ps) pickoff lifetime between the normal brain section and brain section with glioma, further runs with additional samples have showed no statistically significant difference between the normal and tumor tissue for this type of tumor. The o-Ps lifetime in formalin alone was lower than either the normal tissue or glioma sample. So annihilation in the formalin absorbed in the samples would lower the o-Ps lifetime and this may have masked any difference due to the glioma itself. DBS was also used to investigate the difference in positronium formation between tumor and normal tissue. Tissue samples are heterogeneous and this needs to be carefully considered if PALS and DBS are to become useful tools in distinguishing tissue samples.

  20. Positron Spectroscopy Investigation of Normal Brain Section and Brain Section with Glioma Derived from a Rat Glioma Model

    SciTech Connect

    Yang, SH.; Ballmann, C.; Quarles, C. A.

    2009-03-10

    The application of positron annihilation lifetime spectroscopy (PALS) and Doppler broadening spectroscopy (DBS) to the study of animal or human tissue has only recently been reported [G. Liu, et al. phys. stat. sol. (C) 4, Nos. 10, 3912-3915 (2007)]. We have initiated a study of normal brain section and brain section with glioma derived from a rat glioma model. For the rat glioma model, 200,000 C6 cells were implanted in the basal ganglion of adult Sprague Dawley rats. The rats were sacrificed at 21 days after implantation. The brains were harvested, sliced into 2 mm thick coronal sections, and fixed in 4% formalin. PALS lifetime runs were made with the samples soaked in formalin, and there was not significant evaporation of formalin during the runs. The lifetime spectra were analyzed into two lifetime components. While early results suggested a small decrease in ortho-Positronium (o-Ps) pickoff lifetime between the normal brain section and brain section with glioma, further runs with additional samples have showed no statistically significant difference between the normal and tumor tissue for this type of tumor. The o-Ps lifetime in formalin alone was lower than either the normal tissue or glioma sample. So annihilation in the formalin absorbed in the samples would lower the o-Ps lifetime and this may have masked any difference due to the glioma itself. DBS was also used to investigate the difference in positronium formation between tumor and normal tissue. Tissue samples are heterogeneous and this needs to be carefully considered if PALS and DBS are to become useful tools in distinguishing tissue samples.

  1. Imaging of tumor angiogenesis in rat brains in vivo by photoacoustic tomography

    NASA Astrophysics Data System (ADS)

    Ku, Geng; Wang, Xueding; Xie, Xueyi; Stoica, George; Wang, Lihong V.

    2005-02-01

    Green laser pulses at a wavelength of 532 nm from a Q-switched Nd:YAG laser were employed as irradiation sources for photoacoustic tomography (PAT). The vascular structure of the brain was imaged clearly, with optimal contrast, because blood has strong absorption near this wavelength. The photoacoustic images of rat brain tumors in this study clearly reveal the angiogenesis that is associated with tumors. Brain tumors can be identified based on the distorted vascular architecture of brain tumorigenesis and related vascular changes, such as hemorrhage. This research demonstrates that PAT can potentially provide a powerful tool for small-animal biological research.

  2. An autoradiographic map of (3H)diprenorphine binding in rat brain: effects of social interaction

    SciTech Connect

    Panksepp, J.; Bishop, P.

    1981-10-01

    (3H)Diprenorphine binding was analyzed autoradiographically in the brains of 33 day old rat pups. A photographic atlas of diprenorphine binding in the coronal plane is provided to highlight the dispersion of opioid receptor systems through the brain. To determine whether brain opioid release may be induced by social interactions, half the animals were sacrificed following a 30 min period of social interaction while the other half were sacrificed following 30 min of social isolation. Opioid binding was higher in isolate-tested animals than socially-tested ones, suggesting that social interaction may promote endogenous brain opioid release.

  3. Injected tryptophan increases brain but not plasma tryptophan levels more in ethanol treated rats

    SciTech Connect

    Haleem, D.J. )

    1990-01-01

    In the present study ethanol treatment given for two weeks decreased hepatic apo-tryptophan pyrrolase but not total tryptophan pyrrolase activity in rats. Tryptophan levels in plasma and brain did not increase significantly. But there was a marked increase of 5-HT but not 5-hydroxyindoleacetic acid (5-HIAA) concentration in brain, suggesting a possible increase in the activity of tryptophan hydroxylase. The effect of a tryptophan load on brain 5-HT metabolism was therefore compared in controls and ethanol treated rats. One hour after tryptophan injection plasma concentrations of total and free tryptophan were identical in controls and ethanol treated rats, but the increases of brain tryptophan 5-HT and 5-HIAA were considerably greater in the latter group. The results are consistent with long term ethanol treatment enhancing brain serotonin metabolism and show that brain uptake/utilization of exogenous tryptophan is increased in ethanol treated rats and may be useful to understand the role and possible mechanism of tryptophan/serotonin involvement in mood regulation.

  4. Regional brain glucose use in unstressed rats after two days of starvation

    SciTech Connect

    Mans, A.M.; Davis, D.W.; Hawkins, R.A.

    1987-12-01

    Regional brain glucose use was measured in conscious, unrestrained, fed rats and after 2 days of starvation, using quantitative autoradiography and (6-/sup 14/C)glucose. Plasma glucose, lactate, and ketone body concentrations and brain glucose and lactate content were measured in separate groups of rats. Glucose concentrations were lower in starved rats in both plasma and brain; plasma ketone body concentrations were elevated. Glucose use was found to be lower throughout the brain by about 12%. While some areas seemed to be affected more than others, statistical analysis showed that none were exceptionally different. The results could not be explained by increased loss of /sup 14/C as lactate or pyruvate during the experimental period, because the arteriovenous differences of these species were insignificant. The calculated contribution by ketone bodies to the total energy consumption was between 3 and 9% for the brain as a whole in the starved rats and could, therefore, partially account for the depression seen in glucose use. It was concluded that glucose oxidation is slightly depressed throughout the brain after 2 days of starvation.

  5. Chlorpromazine Protects Against Apoptosis Induced by Exogenous Stimuli in the Developing Rat Brain

    PubMed Central

    Li, Yujun; Zhang, Qingmeng; Chen, Yang; Fu, Yingmei; Fang, Wenjuan; Wang, Jindong; Zhong, Zhaohua; Ling, Hong; Zhang, Liming; Zhang, Fengmin

    2011-01-01

    Background Chlorpromazine (CPZ), a commonly used antipsychotic drug, was found to play a neuroprotective role in various models of toxicity. However, whether CPZ has the potential to affect brain apoptosis in vivo is still unknown. The purpose of this study was to investigate the potential effect of CPZ on the apoptosis induced by exogenous stimuli. Methodology The ethanol treated infant rat was utilized as a valid apoptotic model, which is commonly used and could trigger robust apoptosis in brain tissue. Prior to the induction of apoptosis by subcutaneous injection of ethanol, 7-day-old rats were treated with CPZ at several doses (5 mg/kg, 10 mg/kg and 20 mg/kg) by intraperitoneal injection. Apoptotic cells in the brain were measured using TUNEL analysis, and the levels of cleaved caspase-3, cytochrome c, the pro-apoptotic factor Bax and the anti-apoptotic factor Bcl-2 were assessed by immunostaining or western blot. Findings Compared to the group injected with ethanol only, the brains of the CPZ-pretreated rats had fewer apoptotic cells, lower expression of cleaved caspase-3, cytochrome c and Bax, and higher expression of Bcl-2. These results demonstrate that CPZ could prevent apoptosis in the brain by regulating the mitochondrial pathway. Conclusions CPZ exerts an inhibitory effect on apoptosis induced by ethanol in the rat brain, intimating that it may offer a means of protecting nerve cells from apoptosis induced by exogenous stimuli. PMID:21779358

  6. Implants containing beta-amyloid protein are not neurotoxic to young and old rat brain.

    PubMed

    Clemens, J A; Stephenson, D T

    1992-01-01

    Because the cellular effects of beta-amyloid protein (beta-AP) are currently unclear, we evaluated the in vivo effects of beta-AP implants in a lipid matrix to prolong tissue exposure in the brains of rats. Young 3-month-old rats and aged 18-month-old rats received implants of beta-AP prepared in a cocoa butter matrix in the dorsal hippocampus and corpus striatum on one side of the brain and implants of either prolactin or scrambled beta-AP peptide in cocoa butter on the contralateral side. The old rats also received implants of beta-AP embedded in a cholesterol matrix or cholesterol alone in the frontal cortex. The young rats were sacrificed 3-4 days after implantation, while the old rats were sacrificed 6-8 weeks after implantation. Lesion size on the beta-AP implanted side did not differ significantly from lesion size observed with control peptides. Bielschowsky silver staining revealed few argyrophilic neurites and axonal spheroids associated with either beta-AP or control implants. Alz 50 and ubiquitin immunoreactivity were not observed. None of the implant sites demonstrated cytopathology characteristic of Alzheimer's disease. The results of this study indicate that beta-AP implantation into the brains of rats produced no consistent effect beyond that seen with control peptide implants. PMID:1461346

  7. Fluoride-Induced Neuron Apoptosis and Expressions of Inflammatory Factors by Activating Microglia in Rat Brain.

    PubMed

    Yan, Nan; Liu, Yan; Liu, Shengnan; Cao, Siqi; Wang, Fei; Wang, Zhengdong; Xi, Shuhua

    2016-09-01

    Excessive exposure to fluoride results in structural and functional damages to the central nervous system (CNS), and neurotoxicity of fluoride may be associated with neurodegenerative changes. Chronic microglial activation appears to cause neuronal damage through producing proinflammatory cytokines and is involved in many neurodegenerative disorders. It is not known about effects on microglia of fluoride. In the present study, healthy adult Wistar rats were exposed to 60 and 120 ppm fluoride in drinking water for 10 weeks, and control rats received deionized water. After 10 weeks, rats were sacrificed under anesthesia then apoptosis in neuron and inflammatory factors secreted by microglia were determined. We found that apoptosis of neurons in fluoride-treated rat brain increased and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-positive immunofluorescence increased with increasing fluoride concentrations. Bax protein expression increased and Bcl-2 protein expression decreased in fluoride-treated rat brain compared with that of the control rat brain. The microglia in the hippocampus and cortex of fluoride-treated rats were activated by immunostaining with OX-42, a marker of activated microglia, and OX-42-positive microglia cells were more abundant in the hippocampus than in the cortex. The levels of IL-1β and IL-6 protein expression in OX-42-labeled microglial cells were significantly increased in the cortex and hippocampus of rats exposed to fluoride, and TNF-α immunoreactivity in microglial cells of the hippocampus was significantly higher in the 120 ppm fluoride-treated group than that in the control group. Our results indicate that fluoride induced neuron apoptosis and expressions of inflammatory factors by activating microglia in rat brain. PMID:26253724

  8. Brain trace element concentration of rats treated with the plant alkaloid, vincamine.

    PubMed

    Fayed, Abdel-Hasseb A

    2010-09-01

    Trace elements are essential for normal brain functions. Tiny amounts of these elements help in the formation of neurotransmitters and involved in the antioxidant defense and intracellular redox regulation and modulation of neural cells. Vincamine is a plant alkaloid used clinically as a peripheral vasodilator that increases cerebral blood flow and oxygen and glucose utilization by neural tissue to combat the effect of aging. Neurodegenerative diseases associated with aging characterized by a disturbance in trace element levels in the brain. The objective of this study was to determine the level of zinc (Zn), copper (Cu), iron (Fe), Selenium (Se), and chromium (Cr) in the brain of rats treated with vincamine. Vincamine was injected i.m. to rats at a dose of 15 mg/Kg bodyweight daily for 14 days. Twenty-four hours after the last injection, rats were killed, and brains were ashed and digested by concentrated acids and analyzed for trace elements concentrations by flame emission atomic absorption spectrophotometer. The results showed that Zn was the highest trace element in the brain of control rats (3.134 +/- 0.072 ppm) and Cr was the lowest (0.386 +/- 0.027 ppm). Vincamine administration significantly (p < 0.01) reduced the brain Fe concentration (1.393 +/- 0.165 ppm) compared to control (2.807 +/- 0.165 ppm). It was concluded that Zn was the highest trace element in the brain of rats. Vincamine administration resulted in approximately 50% reduction in brain Fe concentration which suggests its beneficial effect to prevent the oxidative stress of Fe in neurodegenerative diseases such as Parkinson's, Alzheimer's, and Huntington's diseases. PMID:19902161

  9. Functional associations among G protein-coupled neurotransmitter receptors in the human brain

    PubMed Central

    2014-01-01

    Background The activity of neurons is controlled by groups of neurotransmitter receptors rather than by individual receptors. Experimental studies have investigated some receptor interactions, but currently little information is available about transcriptional associations among receptors at the whole-brain level. Results A total of 4950 correlations between 100 G protein-coupled neurotransmitter receptors were examined across 169 brain regions in the human brain using expression data published in the Allen Human Brain Atlas. A large number of highly significant correlations were found, many of which have not been investigated in hypothesis-driven studies. The highest positive and negative correlations of each receptor are reported, which can facilitate the construction of receptor sets likely to be affected by altered transcription of one receptor (such sets always exist, but their members are difficult to predict). A graph analysis isolated two large receptor communities, within each of which receptor mRNA levels were strongly cross-correlated. Conclusions The presented systematic analysis shows that the mRNA levels of many G protein-coupled receptors are interdependent. This finding is not unexpected, since the brain is a highly integrated complex system. However, the analysis also revealed two novel properties of global brain structure. First, receptor correlations are described by a simple statistical distribution, which suggests that receptor interactions may be guided by qualitatively similar processes. Second, receptors appear to form two large functional communities, which might be differentially affected in brain disorders. PMID:24438157

  10. Strain-Related Differences after Experimental Traumatic Brain Injury in Rats

    PubMed Central

    Rolfe, Andrew; Register, David; Levasseur, Joseph E.; Churn, Severn B.; Sun, Dong

    2010-01-01

    Abstract The present study directly compares the effects of experimental brain injury in two commonly used rat strains: Fisher 344 and Sprague-Dawley. We previously found that Fisher rats have a higher mortality rate and more frequent seizure attacks at the same injury level than Sprague-Dawley rats. Although strain differences in rats are commonly accepted as contributing to variability among studies, there is a paucity of literature addressing strain influence in experimental neurotrauma. Therefore this study compares outcome measures in two rat strains following lateral fluid percussion injury. Fisher 344 and Sprague-Dawley rats were monitored for changes in physiological measurements, intracranial pressure, and electroencephalographic activity. We further analyzed neuronal degeneration and cell death in the injured brain using Fluoro-Jade-B (FJB) histochemistry and caspase-3 immunostaining. Behavioral studies using the beam walk and Morris water maze were conducted to characterize strain differences in both motor and cognitive functional recovery following injury. We found that Fisher rats had significantly higher intracranial pressure, prolonged seizure activity, increased FJB-positive staining in the injured cortex and thalamus, and increased caspase-3 expression than Sprague-Dawley rats. On average, Fisher rats displayed a greater amount of total recording time in seizure activity and had longer ictal durations. The Fisher rats also had increased motor deficits, correlating with the above results. In spite of these results, Fisher rats performed better on cognitive tests following injury. The results demonstrate that different rat strains respond to injury differently, and thus in preclinical neurotrauma studies strain influence is an important consideration when evaluating outcomes. PMID:20392137

  11. Experimental and numerical study on the mechanical behavior of rat brain tissue.

    PubMed

    Karimi, A; Navidbakhsh, M; Yousefi, H; Haghi, A Motevalli; Sadati, Sja

    2014-02-01

    Brain tissue is a very soft tissue in which the mechanical properties depend on the loading direction. While few studies have characterized these biomechanical properties, it is worth knowing that accurate characterization of the mechanical properties of brain tissue at different loading directions is a key asset for neuronavigation and surgery simulation through haptic devices. In this study, the hyperelastic mechanical properties of rat brain tissue were measured experimentally and computationally. Prepared cylindrical samples were excised from the parietal lobes of rats' brains and experimentally tested by a tensile testing machine. The effects of loading direction on the mechanical properties of brain tissue were measured by applying load on both longitudinal and circumferential directions. The general prediction ability of the proposed hyperelastic model was verified using finite element (FE) simulations of brain tissue tension experiments. The uniaxial experimental results compared well with those predicted by the FE models. The results revealed the influence of loading direction on the mechanical properties of brain tissue. The Ogden hyperelastic material model was suitably represented by the non-linear behavior of the brain tissue, which can be used in future biomechanical simulations. The hyperelastic properties of brain tissue provided here have interest to the medical research community as there are several applications where accurate characterization of these properties are crucial for an accurate outcome, such as neurosurgery, robotic surgery, haptic device design or car manufacturing to evaluate possible trauma due to an impact. PMID:24519528

  12. Relationship between orientation to a blast and pressure wave propagation inside the rat brain.

    PubMed

    Chavko, Mikulas; Watanabe, Tomas; Adeeb, Saleena; Lankasky, Jason; Ahlers, Stephen T; McCarron, Richard M

    2011-01-30

    Exposure to a blast wave generated during an explosion may result in brain damage and related neurological impairments. Several mechanisms by which the primary blast wave can damage the brain have been proposed, including: (1) a direct effect of the shock wave on the brain causing tissue damage by skull flexure and propagation of stress and shear forces; and (2) an indirect transfer of kinetic energy from the blast, through large blood vessels and cerebrospinal fluid (CSF), to the central nervous system. To address a basic question related to the mechanisms of blast brain injury, pressure was measured inside the brains of rats exposed to a low level of blast (~35kPa), while positioned in three different orientations with respect to the primary blast wave; head facing blast, right side exposed to blast and head facing away from blast. Data show different patterns and durations of the pressure traces inside the brain, depending on the rat orientation to blast. Frontal exposures (head facing blast) resulted in pressure traces of higher amplitude and longer duration, suggesting direct transmission and reflection of the pressure inside the brain (dynamic pressure transfer). The pattern of the pressure wave inside the brain in the head facing away from blast exposures assumes contribution of the static pressure, similar to hydrodynamic pressure to the pressure wave inside the brain. PMID:21129403

  13. Melanocortin MC4 receptor agonists alleviate brain damage in abdominal compartment syndrome in the rat.

    PubMed

    Liu, Dong; Zhang, Hong-Guang; Zhao, Zi-Ai; Chang, Ming-Tao; Li, Yang; Yu, Jian; Zhang, Ye; Zhang, Lian-Yang

    2015-02-01

    Intra-abdominal hypertension (IAH) is accompanied by high morbidity and mortality in surgical departments and ICUs. However, its specific pathophysiology is unclear. IAH not only leads to intra-abdominal tissue damage but also causes dysfunction in distal organs, such as the brain. In this study, we explore the protective effects of melanocortin 4 receptor agonists in IAH-induced brain injury. The IAH rat models were induced by hemorrhagic shock/resuscitation (with the mean arterial pressure (MAP) maintained at 30 mm Hg for 90 min followed by the reinfusion of the withdrawn blood with lactated Ringer's solution). Then, air was injected into the peritoneal cavity of the rats to maintain an intra-abdominal pressure of 20 mm Hg for 4 h. The effects of the melanocortin 4 receptor agonist RO27-3225 in alleviating the rats' IAH brain injuries were observed, which indicated that RO27-3225 could reduce brain edema, the expressions of the IL-1β and TNF-α inflammatory cytokines, the blood-brain barrier's permeability and the aquaporin4 (AQP4) and matrix metalloproteinase 9 (MMP9) levels. Moreover, the nicotinic acetylcholine receptor antagonist chlorisondamine and the selective melanocortin 4 receptor antagonist HS024 can negate the protective effects of the RO27-3225. The MC4R agonist can effectively reduce the intracerebral proinflammatory cytokine gene expression and alleviate the brain injury caused by blood-brain barrier damage following IAH. PMID:25616531

  14. Immunological identification and characterization of a delayed rectifier K+ channel polypeptide in rat brain.

    PubMed Central

    Trimmer, J S

    1991-01-01

    Antibodies specific for the drk1 polypeptide were used to characterize the corresponding protein in rat brain. Recombinant and synthetic immunogens containing fragments of the drk1 polypeptide were produced. Antibodies raised to these immunogens display monospecific reactions with the same 130-kDa polypeptide on immunoblots of adult rat brain membranes. Immunoprecipitation of 125I-labeled brain membranes identifies a 38-kDa peptide in tight association with the drk1 polypeptide. Immunohistochemical staining of sections of adult rat cortex shows that drk1 protein is restricted to neurons, where staining is present on dendrites and cell bodies but not on axons. These studies point to the value of such immunological reagents to the further characterization of the components of this delayed rectifier K+ channel in the mammalian central nervous system. Images PMID:1961744

  15. Avocado Oil Improves Mitochondrial Function and Decreases Oxidative Stress in Brain of Diabetic Rats.

    PubMed

    Ortiz-Avila, Omar; Esquivel-Martínez, Mauricio; Olmos-Orizaba, Berenice Eridani; Saavedra-Molina, Alfredo; Rodriguez-Orozco, Alain R; Cortés-Rojo, Christian

    2015-01-01

    Diabetic encephalopathy is a diabetic complication related to the metabolic alterations featuring diabetes. Diabetes is characterized by increased lipid peroxidation, altered glutathione redox status, exacerbated levels of ROS, and mitochondrial dysfunction. Although the pathophysiology of diabetic encephalopathy remains to be clarified, oxidative stress and mitochondrial dysfunction play a crucial role in the pathogenesis of chronic diabetic complications. Taking this into consideration, the aim of this work was to evaluate the effects of 90-day avocado oil intake in brain mitochondrial function and oxidative status in streptozotocin-induced diabetic rats (STZ rats). Avocado oil improves brain mitochondrial function in diabetic rats preventing impairment of mitochondrial respiration and mitochondrial membrane potential (ΔΨ m ), besides increasing complex III activity. Avocado oil also decreased ROS levels and lipid peroxidation and improved the GSH/GSSG ratio as well. These results demonstrate that avocado oil supplementation prevents brain mitochondrial dysfunction induced by diabetes in association with decreased oxidative stress. PMID:26180820

  16. Pharmacological modulation of brain levels of glutamate and GABA in rats exposed to total sleep deprivation

    PubMed Central

    Kamal, Sahar Mohamed

    2010-01-01

    Modulation of gamma-aminobutyric acid (GABA) and glutamate by selected antidepressants and anticonvulsants could play a beneficial role in total sleep deprivation (TSD) caused by depressed mood. In the present study, albino rats were exposed to TSD for five days. On the sixth day, the brains were removed, and GABA and glutamate levels were measured in the prefrontal cortex and thalamus to identify TSD-induced changes in untreated rats and in rats treated with carbamazepine 40 mg/kg intraperitoneally (IP), fluoxetine 20 mg/kg IP, or desipramine 10 mg/kg IP. Carbamazepine and fluoxetine significantly increased GABA and reduced glutamate levels in both brain areas. Desipramine administration did not affect GABA or glutamate concentrations in the tested brain areas; levels were comparable with those induced by TSD without treatment. These results suggest that administration of carbamazepine or fluoxetine could have a beneficial effect by increasing GABA levels during TSD.

  17. Avocado Oil Improves Mitochondrial Function and Decreases Oxidative Stress in Brain of Diabetic Rats

    PubMed Central

    Ortiz-Avila, Omar; Esquivel-Martínez, Mauricio; Olmos-Orizaba, Berenice Eridani; Saavedra-Molina, Alfredo; Rodriguez-Orozco, Alain R.; Cortés-Rojo, Christian

    2015-01-01

    Diabetic encephalopathy is a diabetic complication related to the metabolic alterations featuring diabetes. Diabetes is characterized by increased lipid peroxidation, altered glutathione redox status, exacerbated levels of ROS, and mitochondrial dysfunction. Although the pathophysiology of diabetic encephalopathy remains to be clarified, oxidative stress and mitochondrial dysfunction play a crucial role in the pathogenesis of chronic diabetic complications. Taking this into consideration, the aim of this work was to evaluate the effects of 90-day avocado oil intake in brain mitochondrial function and oxidative status in streptozotocin-induced diabetic rats (STZ rats). Avocado oil improves brain mitochondrial function in diabetic rats preventing impairment of mitochondrial respiration and mitochondrial membrane potential (ΔΨm), besides increasing complex III activity. Avocado oil also decreased ROS levels and lipid peroxidation and improved the GSH/GSSG ratio as well. These results demonstrate that avocado oil supplementation prevents brain mitochondrial dysfunction induced by diabetes in association with decreased oxidative stress. PMID:26180820

  18. Effect of mealing on plasma and brain amino acid, and brain monoamine in rats after oral aspartame.

    PubMed

    Torii, K; Mimura, T; Takasaki, Y; Ichimura, M

    1986-01-01

    Aspartame (APM; L-aspartyl-L-phenylalanine methyl ester) was investigated for its ability to alter brain amino acids and monoamines in overnight fasted rats allowed to consume commercial diets for 60 minutes. In addition, the effects of mealing on the changes in plasma and brain amino acids and brain monoamines induced by glucose and/or insulin, and known pharmacologically active compounds, were studied. The consumption of the commercial chow largely prevented changes in blood glucose and amino acids, and brain amino acids and the monoamines dopamine, norepinephrine and serotonin that might be expected to occur following glucose with or without insulin. Feeding failed to prevent changes in the above parameters when 5-hydroxy-tryptophan, p-chlorophenylalanine and reserpine were administered. The oral administration of up to 250 mg/kg BW APM with water or glucose followed by free feeding failed to alter brain monoamines. These studies demonstrate the potent ability of food to normalize biochemical parameters in blood and brain that otherwise might occur, and clearly show the lack of effect on brain monoamine levels of abuse doses of APM when administered with food. PMID:2940610

  19. Expression of Aquaporin 4 and Breakdown of the Blood-Brain Barrier after Hypoglycemia-Induced Brain Edema in Rats

    PubMed Central

    Deng, Jiangshan; Zhao, Fei; Yu, Xiaoyan; Zhao, Yuwu; Li, Dawei; Shi, Hong; Sun, Yongning

    2014-01-01

    Background Hypoglycemia-induced brain edema is a severe clinical event that often results in death. The mechanisms by which hypoglycemia induces brain edema are unclear. Methods In a hypoglycemic injury model established in adult rats, brain edema was verified by measuring brain water content and visualizing water accumulation using hematoxylin and eosin staining. Temporal expression of aquaporin 4 (AQP4) and the integrity of the blood-brain barrier (BBB) were evaluated. We assessed the distribution and expression of AQP4 following glucose deprivation in astrocyte cultures. Results Brain edema was induced immediately after severe hypoglycemia but continued to progress even after recovery from hypoglycemia. Upregulation of AQP4 expression and moderate breakdown of the BBB were observed 24 h after recovery. In vitro, significant redistribution of AQP4 to the plasma membrane was induced following 6 h glucose deprivation. Conclusion Hypoglycemia-induced brain edema is caused by cytotoxic and vasogenic factors. Changes in AQP4 location and expression may play a protective role in edema resolution. PMID:25264602

  20. Blood-brain barrier transport of choline is reduced in the aged rat.

    PubMed

    Mooradian, A D

    1988-02-01

    An age-related impairment in choline transport across the blood-brain barrier (BBB) may contribute to the cholinergic mechanisms of geriatric memory dysfunction. To test this hypothesis, the brain choline uptake in male Fisher 344 rats at 2, 18 and 24 months of age was studied using the Oldendorf technique. The Vmax of choline transport in the 24-month-old rats (0.05 +/- 0.04 nmol/min/g) was significantly lower than that in the 2-month-old rat (2.5 +/- 1.0 nmol/min/g) (P less than 0.05). The Km of transport in old rats (13 +/- 35 microM) was also significantly smaller than the value in 24-month-old rats (450 +/- 195 microM), while the constant of the non-saturable component of the transport, Kd, was not significantly different in older rats (1.2 +/- 0.3 vs 0.6 +/- 0.1 microliter/min/g). These results indicate that the carrier in old rats has reduced capacity and increased affinity to choline. The reduced choline carrier capacity explains the significant decrease in BBB choline transport in aged rats. PMID:3359216

  1. Pharmacokinetics and distribution of fluvoxamine to the brain in rats under oxidative stress.

    PubMed

    Kobuchi, Shinji; Fukushima, Keizo; Ito, Yukako; Sugioka, Nobuyuki; Takada, Kanji

    2012-07-01

    The effects of oxidative stress (OS) on the pharmacokinetics of fluvoxamine (FLV), particularly on FLV distribution in the plasma, were studied in ferric-nitrilotriacetate-induced OS rat models (OS rats). The study protocol involved a continuous FLV infusion (25.0 μg/kg/min). The resulting mean plasma FLV concentration measured in steady state OS rats was 0.13 ± 0.01 μg/mL, which was significantly lower than plasma concentrations measured in control rats (0.19 ± 0.01 μg/mL). Moreover, the mean FLV concentration in the OS rat brain (0.51 ± 0.08 μg/g) was determined to be approximately half the concentration in control rat brains (0.95 ± 0.11 μg/g). The FLV concentrations in both the unbound fraction of plasma and erythrocytes of OS rats were significantly greater than that of control rats. These results suggest the potential attenuation of FLV's pharmacological effects in patients under OS. PMID:22486632

  2. Characterization and in vivo regulation of V sub 1 -type vasopressin receptors in the rat brain

    SciTech Connect

    Shewey, L.M.

    1988-01-01

    Specific, high affinity binding sites for ({sup 3}H)-arginine{sup 8}-vasopressin (AVP) have been characterized in Long-Evans rat septal membranes. Binding displacement studies with peptide analogs of AVP indicate that this binding site is similar to the V{sub 1} (pressor)-type receptor for AVP. When added to rat brain septal slices that had been pre-labeled with ({sup 3}H)-myoinositol, AVP stimulated the accumulation of ({sup 3}H)-inositol-1-phosphate (IP{sub 1}) in the presence of lithium in a dose-dependent manner. This stimulation was completely inhibited by the specific V{sub 1} antagonists, d(CH{sub 2}){sub 5}Tyr(Me)AVP, indicating that AVP stimulates hydrolysis of inositol phospholipids in rat brain septum through an interaction with V{sub 1}-type AVP receptors. Binding studies of AVP receptors in the septum of heterozygous (HE) and homozygous, Brattleboro (BB) rats revealed an increased number of receptors with a lower affinity for AVP in the HO-BB rat when compared to the HE-BB rat. AVP-stimulated accumulation of ({sup 3}H)-IP{sub 1} was significantly greater in the septum of the HO-BB rat than in the HE-BB rat. AVP receptor binding capacity correlated with release of ({sup 3}H)-IP{sub 1} for all three groups studied.

  3. Impact of acute and chronic stress hormone on male albino rat brain

    PubMed Central

    Han, Li-Li; Chen, Ling; Dong, Zhi-Ling

    2015-01-01

    The present investigation aimed to evaluate the acute and chronic effect of stress (stress hormone) in male albino rat brain. Nor-epinephrine was used for the treatment and saline used for the control. Nor-epinephrine was dissolved in the saline and administered orally to the rats. Following nor-epinephrine administration, the brain was removed surgically at 6 h, 12 h and 45 days. Alanine tansaminase (ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP) were significantly altered in the rats. Lipid peroxidation was measured as malondialdehyde (MDA), showed altered lipid peroxidation. Hematological markers such as packed cell volume (PCV), white blood cells (WBC), neutrophil, lymphocytes and hemoglobin were significantly altered compared to controls. Altered serum biochemical and hematological markers, lipid peroxidation and enzyme activities leads to adverse effect in the cellular metabolism and physiological activities of rats. PMID:26261571

  4. Neurotransmitters couple brain activity to subventricular zone neurogenesis

    PubMed Central

    Young, Stephanie Z.; Taylor, M. Morgan; Bordey, Angélique

    2011-01-01

    Adult neurogenesis occurs in two privileged microenvironments, the hippocampal subgranular zone of the dentate gyrus and the subventricular zone (SVZ) along the lateral ventricle. This review focuses on accumulating evidence suggesting that the activity of specific brain regions or bodily states influences SVZ cell proliferation and neurogenesis. Neuromodulators such as dopamine and serotonin have been shown to have long-range effects through neuronal projections into the SVZ. Local GABA and glutamate signaling have demonstrated effects on SVZ proliferation and neurogenesis, but an extra-niche source of these neurotransmitters remains to be explored and options will be discussed. There is also accumulating evidence that diseases and bodily states such as Alzheimer's disease, seizures, sleep, and pregnancy influence SVZ cell proliferation. With such complex behavior and environmentally-driven factors that control subregion-specific activity, it will become necessary to account for overlapping roles of multiple neurotransmitter systems on neurogenesis when developing cell therapies or drug treatments. PMID:21395856

  5. Metabolic brain activity suggestive of persistent pain in a rat model of neuropathic pain

    PubMed Central

    Thompson, Scott J; Millecamps, Magali; Aliaga, Antonio; Seminowicz, David A; Low, Lucie A; Bedell, Barry J; Stone, Laura S; Schweinhardt, Petra; Bushnell, M Catherine

    2014-01-01

    Persistent pain is a central characteristic of neuropathic pain conditions in humans. Knowing whether rodent models of neuropathic pain produce persistent pain is therefore crucial to their translational applicability. We investigated the Spared Nerve Injury (SNI) model of neuropathic pain and the formalin pain model in rats using Positron Emission Tomography (PET) with the metabolic tracer [18F]fluorodeoxyglucose (FDG) to determine if there is ongoing brain activity suggestive of persistent pain. For the formalin model, under brief anesthesia we injected one hindpaw with 5% formalin and the FDG tracer into a tail vein. We then allowed the animals to awaken and observed pain behavior for 30 min during the FDG uptake period. The rat was then anesthetized and placed in the scanner for static image acquisition, which took place between minutes 45 and 75 post-tracer injection. A single reference rat brain magnetic resonance image (MRI) was used to align the PET images with the Paxinos and Watson rat brain atlas. Increased glucose metabolism was observed in the somatosensory region associated with the injection site (S1 hindlimb contralateral), S1 jaw/upper lip and cingulate cortex. Decreases were observed in the prelimbic cortex and hippocampus. Second, SNI rats were scanned 3 weeks post-surgery using the same scanning paradigm, and region-of-interest analyses revealed increased metabolic activity in the contralateral S1 hindlimb. Finally, a second cohort of SNI rats were scanned while anesthetized during the tracer uptake period, and the S1 hindlimb increase was not observed. Increased brain activity in the somatosensory cortex of SNI rats resembled the activity produced with the injection of formalin, suggesting that the SNI model may produce persistent pain. The lack of increased activity in S1 hindlimb with general anesthetic demonstrates that this effect can be blocked, as well as highlights the importance of investigating brain activity in awake and behaving

  6. Maternal separation produces alterations of forebrain brain-derived neurotrophic factor expression in differently aged rats

    PubMed Central

    Wang, Qiong; Shao, Feng; Wang, Weiwen

    2015-01-01

    Early life adversity, such as postnatal maternal separation (MS), play a central role in the development of psychopathologies during individual ontogeny. In this study, we investigated the effects of repeated MS (4 h per day from postnatal day (PND) 1–21) on the brain-derived neurotrophic factor (BDNF) expression in the medial prefrontal cortex (mPFC), the nucleus accumbens (NAc) and the hippocampus of male and female juvenile (PND 21), adolescent (PND 35) and young adult (PND 56) Wistar rats. The results indicated that MS increased BDNF in the CA1 and the dentate gyrus (DG) of adolescent rats as well as in the DG of young adult rats. However, the expression of BDNF in the mPFC in the young adult rats was decreased by MS. Additionally, in the hippocampus, there was decreased BDNF expression with age in both the MS and non separated rats. However, in the mPFC, the BDNF expression was increased with age in the non separated rats; nevertheless, the BDNF expression was significantly decreased in the MS young adult rats. In the NAc, the BDNF expression was increased with age in the male non-maternal separation (NMS) rats, and the young adult female MS rats had less BDNF expression than the adolescent female MS rats. The present study shows unique age-differently changes on a molecular level induced by MS and advances the use of MS as a valid animal model to detect the underlying neurobiological mechanisms of mental disorders. PMID:26388728

  7. Intracellular pathways regulating ciliary beating of rat brain ependymal cells

    PubMed Central

    Nguyen, Thien; Chin, Wei-Chun; O’Brien, Jennifer A; Verdugo, Pedro; Berger, Albert J

    2001-01-01

    The mammalian brain ventricles are lined with ciliated ependymal cells. As yet little is known about the mechanisms by which neurotransmitters regulate cilia beat frequency (CBF). Application of 5-HT to ependymal cells in cultured rat brainstem slices caused CBF to increase. 5-HT had an EC50 of 30 μM and at 100 μM attained a near-maximal CBF increase of 52.7 ± 4.1 % (mean ± s.d.) (n= 8). Bathing slices in Ca2+-free solution markedly reduced the 5-HT-mediated increase in CBF. Fluorescence measurements revealed that 5-HT caused a marked transient elevation in cytosolic Ca2+ ([Ca2+]c) that then slowly decreased to a plateau level. Analysis showed that the [Ca2+]c transient was due to release of Ca2+ from inositol 1,4,5-trisphosphate (IP3)-sensitive stores; the plateau was probably due to extracellular Ca2+ influx through Ca2+ release-activated Ca2+ (CRAC) channels. Application of ATP caused a sustained decrease in CBF. ATP had an EC50 of about 50 μM and 100 μM ATP resulted in a maximal 57.5 ± 6.5 % (n= 12) decrease in CBF. The ATP-induced decrease in CBF was unaffected by lowering extracellular [Ca2+], and no changes in [Ca2+]c were observed. Exposure of ependymal cells to forskolin caused a decrease in CBF. Ciliated ependymal cells loaded with caged cAMP exhibited a 54.3 ± 7.5 % (n= 9) decrease in CBF following uncaging. These results suggest that ATP reduces CBF by a Ca2+-independent cAMP-mediated pathway. Application of 5-HT and adenosine-5′-O-3-thiotriphosphate (ATP-γ-S) to acutely isolated ciliated ependymal cells resulted in CBF responses similar to those of ependymal cells in cultured slices suggesting that these neurotransmitters act directly on these cells. The opposite response of ciliated ependymal cells to 5-HT and ATP provides a novel mechanism for their active involvement in central nervous system signalling. PMID:11179397

  8. Neuroprotection by Vitamin C Against Ethanol-Induced Neuroinflammation Associated Neurodegeneration in the Developing Rat Brain.

    PubMed

    Ahmad, Ashfaq; Shah, Shahid A; Badshah, Haroon; Kim, Min J; Ali, Tahir; Yoon, Gwang H; Kim, Tae H; Abid, Nouman B; Rehman, Shafiq Ur; Khan, Sohail; Kim, Myeong O

    2016-01-01

    Ethanol induces oxidative stress and its exposure during early developmental age causes neuronal cell death which leads to several neurological disorders. We previously reported that vitamin C can protect against ethanol-induced apoptotic cell death in the developing rat brain. Here, we extended our study to understand the therapeutic efficacy of vitamin C against ethanol-induced oxidative stress, neuroinflammation mediated neurodegeneration in postnatal day 7 (PND7) rat. A single episode of ethanol (5g/kg) subcutaneous administration to postnatal day 7 rat significantly induced the production of reactive oxygen species (ROS), and activated both microglia and astrocytes followed by the induction of different apoptotic markers. On the other hand, due to its free radical scavenging properties, vitamin C treatment significantly reduced the production of reactive oxygen species, suppressed both activated microglia and astrocytes and reversed other changes including elevated level of Bax/Bcl-2 ratio, cytochrome c and different caspases such as caspase-9 and caspase-3 induced by ethanol in developing rat brain. Moreover, vitamin C treatment also reduced ethanol-induced activation of Poly [ADP-Ribose] Polymerase 1(PARP-1) and neurodegeneration as evident from Flouro-Jade-B and Nissl stainined neuronal cell death in PND7 rat brain. These findings suggest that vitamin C mitigated ethanol-induced oxidative stress, neuroinflammation and apoptotic neuronal loss and may be beneficial against ethanol damaging effects in brain development. PMID:26831257

  9. Radioprotective effects of valproic acid, a histone deacetylase inhibitor, in the rat brain

    PubMed Central

    ZHOU, YONG; NIU, JUNJIE; LI, SHUPENG; HOU, HUAYING; XU, YING; ZHANG, WEI; JIANG, YUHUA

    2015-01-01

    Radiotherapy is commonly used in the treatment of brain tumors but can cause significant damage to surrounding normal brain. The radioprotective effects of valproic acid (VPA) on normal tissue in the rat brain were evaluated following irradiation. Male Wistar rats were used in the present study and 48 rats were randomly divided into four groups consisting of 12 rats each. The whole-brain irradiation (WBI) was delivered by X-ray and the rats received the following treatment once a day for 5 days. The control group (sham-exposed group) received sham irradiation plus physiological saline. The VPA group received sham irradiation plus 150 mg VPA/kg. The X-ray group received WBI plus physiological saline. The combined group received WBI plus 150 mg/kg intraperitoneally VPA. A total of 6 months post-irradiation, the rats were sacrificed and the brains were harvested. Cell apoptosis in the cortex was determined by immunohistochemistry 24 h post-irradiation using an antibody for protein caspase-3. Transmission electron microscope (TEM) analyses were used to assess the effects of VPA on the radioprotection of rat normal brain cells 6 months post-irradiation. The weights of the animals in the TEM group measured over the two weeks after the first injection of VPA were also observed. Histological findings demonstrated that apoptosis occurred on the cortex 1 day after treatment, peaking in the X-ray group. The cells of the combined group showed a moderate caspase-3 staining compared to the X-ray group. There was a trend towards a lower body weight of the X-ray group following irradiation compared to either no-irradiation or rats of the combined group, although there was no significant difference in the average weight between the combined group and irradiated rats. Mild swelling of the capillary endothelial cells in the irregular lumen was observed in the combined group, whereas the X-ray group showed a severe structural disorder. In conclusion, VPA supplementation during

  10. Element distribution in the brain sections of rats measured by synchrotron radiation X-ray fluorescence

    NASA Astrophysics Data System (ADS)

    Liu, N. Q.; Zhang, F.; Wang, X. F.; Zhang, Z. Y.; Chai, Z. F.; Huang, Y. Y.; He, W.; Zhao, X. Q.; Zuo, A. J.; Yang, R.

    2004-02-01

    The concentration of trace elements in brain sections was measured by synchrotron radiation X-ray fluorescence. The relative concentration was calculated by means of the normalization of Compton scattering intensity approximately 22 keV, after the normalization for collecting time of X-ray spectrum and the counting of the ion chamber, and subtracting the contribution of the polycarbonate film for supporting sample. Furthermore, the statistical evaluation of the element distribution in various regions of the brain sections of the 20-day-old rats was tested. For investigating the distribution of elements in the brain of iodine deficient rats, Wistar rats were fed with iodine deficient diet and deionized water (ID group). The rats were fed the same iodine deficient diet, but drank KIO 3 solution as control (CT group). The results showed that the contents of calcium (Ca) in thalamus (TH) and copper (Cu) and iron (Fe) in cerebral cortex (CX) of ID rats were significantly lower than that of control rats, while the contents of phosphor (P), sulfur (S), potassium (K), rubidium (Rb), bromine (Br), chlorine (Cl), zinc (Zn), Ca and Cu of ID in hippocampus (H) and the contents of Br, Cl, Zn and Ca in cerebral cortex of ID rats were significantly higher. Especially, the difference of Br, Cl, Zn and Ca in H between ID and CT was more significant. The contents of all elements measured in H were higher than (or equal to) CX and/or TH for both groups, except low Cl of the control rats. Furthermore Zn and Cu contents along the hippocampal fissure in both groups were 1.5 ( P<0.001) and 0.87( P<0.03) times higher than in hippocampus, respectively. Considering the results of cluster analysis our study shows that the marked alterations in the spatial distribution of Zn and Ca of ID rats brain during brain development stages. In addition, the effect of the perfusion with 0.9% NaCl solution before taking brain on the distribution of elements in the brain sections was observed and

  11. Comparison of (/sup 125/I)beta-endorphin binding to rat brain and NG108-15 cells using a monoclonal antibody directed against the opioid receptor

    SciTech Connect

    Bidlack, J.M.; O'Malley, W.E.; Schulz, R.

    1988-02-01

    The properties of (/sup 125/I)beta h-endorphin-binding sites from rat brain membranes and membranes from the NG108-15 cell line were compared using a monoclonal antibody directed against the opioid receptor and opioid peptides as probes. The binding of (/sup 125/I)beta h-endorphin to both rat brain and NG108-15 membranes yielded linear Scatchard plots with Kd values of 1.2 nM and 1.5 nM, respectively, and Bmax values of 865 fmol/mg rat brain membrane protein and 1077 fmol/mg NG108-15 membrane protein. A monoclonal antibody, OR-689.2.4, capable of inhibiting mu and delta binding but not kappa binding to rat brain membranes, noncompetitively inhibited the binding of 1 nM (/sup 125/I)beta h-endorphin to rat brain and NG108-15 membranes with an IC50 value of 405 nM for rat brain membranes and 543 nM for NG108-15 membranes. The monoclonal antibody also inhibited the binding of 3 nM (/sup 3/H) (D-penicillamine2, D-penicillamine5) enkephalin to NG108-15 membranes with an IC50 value of 370 nM. In addition to blocking the binding of (/sup 125/I)beta h-endorphin to brain membranes, the antibody also displaced (/sup 125/I)beta h-endorphin from membranes. Site-specific opioid peptides had large variations in their IC50 values depending on whether they were inhibiting (/sup 125/I)beta h-endorphin binding to rat brain or the NG108-15 membranes. When the peptides were tested with the monoclonal antibody for their combined ability to inhibit (/sup 125/I)beta h-endorphin binding to both membrane preparations, the peptides and antibody blocked binding as though they were acting at allosterically coupled sites, not two totally independent sites. These studies suggest that mu-, delta-, and beta-endorphin-binding sites share some sequence homology with the 35,000-dalton protein that the antibody is directed against.

  12. Imaging of water distribution in the rat brain by activation autoradiography

    SciTech Connect

    Kogure, K.; Kawashima, K.; Iwata, R.; Ido, T. )

    1990-01-01

    Regional water distribution in the rat brain was obtained autoradiographically by activation analysis. The autoradiogram obtained for the normal rat brain showed high accumulation of water in the areas of sensory-motor cortex, hippocampus, thalamus, and amygdaloid cortex, whereas corpus callosum and internal capsule showed low water contents as expected. The estimated values of water content were 78.6 +/- 4.9 weight % for gray matter, and 73.5 +/- 4.9 weight % for white matter, respectively. The mean values of the water content were consistent with those obtained by a conventional drying-weighing method.

  13. 26Al incorporation into the brain of rat fetuses through the placental barrier and subsequent metabolism in postnatal development

    NASA Astrophysics Data System (ADS)

    Yumoto, Sakae; Nagai, Hisao; Kakimi, Shigeo; Matsuzaki, Hiroyuki

    2010-04-01

    Aluminium (Al) inhibits prenatal and postnatal development of the brain. We used 26Al as a tracer, and measured 26Al incorporation into rat fetuses through the placental barrier by accelerator mass spectrometry (AMS). From day 15 to day 18 of gestation, 26AlCl 3 was subcutaneously injected into pregnant rats. Considerable amounts of 26Al were measured in the tissues of newborn rats immediately after birth. The amounts of 26Al in the liver and kidneys decreased rapidly during postnatal development. However, approximately 15% of 26Al incorporated into the brain of fetuses remained in the brain of adult rats 730 days after birth.

  14. Brain macrophages in rats following intravenous labelling of mononuclear leucocytes with colloidal carbon.

    PubMed Central

    Ling, E A

    1978-01-01

    Intravenous injections of colloidal carbon were used to label circulating mononuclear leucocytes. In the neonatal rats (3-5 days old), either 24 or 48 hours later, carbon-labelled macrophages were seen in the brain tissue. In the areas examined, notably the corpus callosum and the cerebral cortex, labelled macrophages were distributed randomly. They were either perivascular, perineuronal or lay between the nerve fibres. The labelled cells were mostly spindle-shaped with an eccentric nucleus and the cytoplasm at one pole of the cell was engorged with dark carbon particles. Abundant labelled cells were also seen over the brain surface in the layers of meninges. There was no evidence of leucocytic infiltration into the brain tissue of mature animals. It is concluded from the present work that a proportion (but not all) of the macrophages in the neonatal rat brain are derived from the blood stream. Images Figs. 1-8 PMID:632205

  15. Chitosan and cyclodextrin in intranasal microemulsion for improved brain buspirone hydrochloride pharmacokinetics in rats.

    PubMed

    Bshara, Hamza; Osman, Rihab; Mansour, Samar; El-Shamy, Abd El-Hameed A

    2014-01-01

    The aim of this study was to develop buspirone hydrochloride microemulsion formulations for intranasal administration to improve the drug bioavailability and provide high drug brain levels. For the purpose, chitosan aspartate, and hydroxypropyl-β-cyclodextrin were incorporated in the microemulsions. The prepared formulations were characterized. Biological investigations including pharmacokinetic studies, brain drug targeting efficiency determinations and histopathological examinations were performed on rats. The results showed that safe and stable mucoadhesive microemulsion suitable for nasal administration were successfully prepared. Ex vivo drug permeation revealed high drug permeation from microemulsions. Absolute bioavailability after intranasal administration of buspirone mucoadhesive microemulsion increased significantly and plasma concentration peaked at 15 min. The AUC0-360(brain) was 3 times that obtained after intravenous administration. A high brain targeting efficiency (86.6%) and a direct nose to brain transport (88%) confirmed the direct nose to brain transport of buspirone following nasal administration of the microemulsions. PMID:24274510

  16. CARBONYL SULFIDE INHALATION PRODUCES BRAIN LESIONS IN F344 RATS.

    EPA Science Inventory

    Carbonyl sulfide (COS) is an intermediate in the production of pesticides and herbicides, and is a metabolite of the neurotoxicant carbon disulfide. The potential neurotoxicity of inhaled COS was investigated in F344 rats. Male rats were exposed to 0, 75, 150, 300, or 600 ppm COS...

  17. Aging and sex influence the permeability of the blood-brain barrier in the rat

    SciTech Connect

    Saija, A.; Princi, P.; D'Amico, N.; De Pasquale, R.; Costa, G.

    1990-01-01

    The aim of the present study was to investigate the existence of aging- and sex-related alterations in the permeability of the blood-brain barrier (BBB) in the rat, by calculating a unidirectional blood-to-brain transfer constant (Ki) for the circulating tracer ({sup 14}C)-{alpha}-aminoisobutyric acid. The authors observed that: (a) the permeability of the BBB significantly increased within the frontal and temporo-parietal cortex, hypothalamus and cerebellum in 28-30 week old rats, in comparison with younger animals; (b) in several brain areas of female intact rats higher Ki values (even though not significantly different) were calculated at oestrus than at proestrus; (c) in 1-week ovariectomized rats there was a marked increase of Ki values at the level of the frontal, temporo-parietal and occipital cortex, cerebellum and brain-stem. One can speculate that aging and sex-related alterations in thee permeability of the BBB reflect respectively changes in brain neurochemical system activity and in plasma steroid hormone levels.

  18. Acetylcholine content in the brain of rats treated with paraoxon and obidoxime

    PubMed Central

    Milošević, M. P.

    1970-01-01

    1. The effect of obidoxime on the rise in brain acetylcholine caused by the anticholinesterase paraoxon was studied in the rat. 2. In animals poisoned with a sublethal dose of paraoxon and thereafter treated with obidoxime the levels of both “free” and total brain acetylcholine were practically the same as those in rats injected with paraoxon only. 3. After poisoning with doses of paraoxon which are lethal unless an oxime is also given, the total acetylcholine in the brain of obidoxime-protected rats continued to accumulate, reaching a peak 2 h after injection of paraoxon. At this time no signs of central effects such as convulsions or tremor were seen. 4. Atropine, given 30 min before paraoxon, markedly reduced the rise in total brain acetylcholine seen when the anticholinesterase is given alone. 5. In rats pretreated with atropine and obidoxime excessive doses of paraoxon which are lethal in the absence of the antidotes produced a rise in total brain acetylcholine which was directly proportional to the dose of paraoxon administered. PMID:5485148

  19. Brain oxidative damage restored by Sesbania grandiflora in cigarette smoke-exposed rats.

    PubMed

    Ramesh, Thiyagarajan; Sureka, Chandrabose; Bhuvana, Shanmugham; Begum, Vavamohaideen Hazeena

    2015-08-01

    Cigarette smoking has been associated with high risk of neurological diseases such as stroke, Alzheimer's disease, multiple sclerosis, etc., The present study was designed to evaluate the restorative effects of Sesbania grandiflora (S. grandiflora) on oxidative damage induced by cigarette smoke exposure in the brain of rats. Adult male Wistar-Kyoto rats were exposed to cigarette smoke for a period of 90 days and consecutively treated with S. grandiflora aqueous suspension (SGAS, 1000 mg/kg body weight per day by oral gavage) for a period of 3 weeks. The levels of protein carbonyl, nitric oxide, and activities of cytochrome P450, NADPH oxidase and xanthine oxidase were significantly increased, whereas the levels of total thiol, protein thiol, non-protein thiol, nucleic acids, tissue protein and the activities of Na(+)/K(+)-ATPase, Ca(2+)-ATPase and Mg(2+)-ATPase were significantly diminished in the brain of rats exposed to cigarette smoke as compared with control rats. Also cigarette smoke exposure resulted in a significant alteration in brain total lipid, total cholesterol, triglycerides and phospholipids content. Treatment of SGAS is regressed these alterations induced by cigarette smoke. The results of our study suggest that S. grandiflora restores the brain from cigarette smoke induced oxidative damage. S. grandiflora could have rendered protection to the brain by stabilizing their cell membranes and prevented the protein oxidation, probably through its free radical scavenging and anti-peroxidative effect. PMID:25620659

  20. Increased concentrations of 3-hydroxykynurenine in vitamin B6 deficient neonatal rat brain.

    PubMed

    Guilarte, T R; Wagner, H N

    1987-12-01

    Increased concentrations of the endogenous tryptophan metabolite 3-hydroxykynurenine (3-HK) were measured in the brains of vitamin B6 deficient neonatal rats. Mean concentrations of 3-HK in B6 deficient cerebellum, corpus striatum, frontal cortex, and pons/medulla ranged from 9.7 to 18.6 and 102 to 142 nmol/g of wet tissue at 14 and 18 days of age, respectively. 3-HK was not significantly increased in control neonatal or adult rat brain, vitamin B6 deficient rat brain at 7 days of age, or in brains from adult rats deprived of vitamin B6 for 58 days. The administration of daily intraperitoneal injections of vitamin B6 from the 14th to the 18th day of age decreased the concentration of 3-HK to control levels. 3-HK has been shown by other investigators to produce seizures when injected into the cerebral ventricles of adult rodents. Thus, our studies show the accumulation in brain of a putative endogenous convulsant as the result of a nutritional deficiency. PMID:3681302

  1. Effects of atrial and brain natriuretic peptides upon cyclic GMP levels, potassium transport, and receptor binding in rat astrocytes

    SciTech Connect

    Beaumont, K.; Tan, P.K. )

    1990-02-01

    The ability of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) to alter cyclic GMP levels and NaKCl cotransport in rat neocortical astrocytes was determined. At concentrations of 10(-9)-10(-6) M, rat ANP99-126 (rANF), rat ANP102-126 (auriculin B), and rat ANP103-126 (atriopeptin III) stimulated 6- to 100-fold increases in cyclic GMP levels. Porcine BNP (pBNP) and rat BNP (rBNP) were 20%-90% as effective as rANF over most of this concentration range, although 10(-6) M pBNP produced a greater effect than rANF. NaKCl cotransport as measured by bumetanide-sensitive 86Rb+ influx was not altered by exposure of astrocytes to 10(-6)M rANF, pBNP, or rBNP. Both pBNP and rBNP, as well as rat ANP103-123 (atriopeptin I) and des(gl18, ser19, gly20, leu21, gly22) ANF4-23-NH2 (C-ANF4-23) strongly competed for specific 125I-rANF binding sites in astrocyte membranes with affinities ranging from 0.03 to 0.4 nM, suggesting that virtually all binding sites measured at subnanomolar concentrations of 125I-rANF were of the ANP-C (ANF-R2) receptor subtype. These receptors are thought to serve a clearance function and may be linked to a guanylate cyclase activity that is chemically and pharmacologically distinct from that coupled to ANP-A (ANF-R1) receptors. ANP receptors on astrocytes may function in limiting the access of ANP and BNP to neurons involved in body fluid and cardiovascular regulation.

  2. Cholestasis induced antinociception and decreased gene expression of MOR1 in rat brain.

    PubMed

    Ahmadi, S; Karami, Z; Mohammadian, A; Khosrobakhsh, F; Rostamzadeh, J

    2015-01-22

    We examined antinociception and gene expression of mu-opioid receptor 1 (MOR1) in some brain areas of cholestatic rats, 21 days after common bile duct ligation (BDL). Cholestasis was induced in male Wistar rats during laparotomy and common BDL. Pain behavior was assessed on days 7, 14 or 21 of BDL using a hotplate test in control, sham and cholestatic groups. On day 21 of BDL, other groups of rats were sacrificed, whole brains were extracted, and the hypothalamus, prefrontal cortex (PFC), hippocampus and striatum in control, sham and cholestatic rats were dissected. We used a semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) method for evaluating MOR1 gene expression. The results revealed that cholestatic rats showed significant antinociception on days 14 and 21 of ligation with the most significant effect on day 21, which was prevented by naloxone (1 mg/kg). On the other hand, the expression of MOR1 gene compared to the sham group was decreased by 42% in the hypothalamus, 41% in the PFC, and 67% in the hippocampus after 21 days of BDL, while no significant change in its expression in the striatum was observed. It can be concluded that a change in endogenous opioid levels and its subsequent influence on the gene expression of MOR in some areas of the rat brain may underlie the altered nociception and other possible pathological changes such as pruritus after induction of cholestasis. PMID:25290008

  3. Spontaneous Wheel Running Exercise Induces Brain Recovery via Neurotrophin-3 Expression Following Experimental Traumatic Brain Injury in Rats.

    PubMed

    Koo, Hyun Mo; Lee, Sun Min; Kim, Min Hee

    2013-09-01

    [Purpose] The aim of the present study was to investigate the expression of neurotrophin-3 (NT-3) after applying spontaneous wheel running exercises (SWR) after experimental traumatic brain injury (TBI). [Subjects and Methods] Thirty male Sprague-Dawley rats were divided into 3 groups; 20 rats were subjected to controlled cortical impact for TBI, and then, animals were randomly collected from the SWR group and subjected to wheel running exercise for 3 weeks. Ten rats were not subjected to any injury or running exercise to compare with the effect of TBI and SWR. Immunohistochemistry, Western blotting, skilled ladder rung walking test, and 2,3,5-triphenyltetrazolium chloride staining analysis for the evaluation of NT-3 expression were used to assess brain damage and recovery. [Results] The TBI-induced decrease in NT-3 expression was recovered by wheel running exercise. Moreover, decreased ischemic volume and progressive neurobehavioral outcome were observed in the SWR group. [Conclusion] Spontaneous running exercise promotes brain recovery and motor function through an increase in expression of NT-3. PMID:24259924

  4. Dynamic coupling of complex brain networks and dual-task behavior.

    PubMed

    Alavash, Mohsen; Thiel, Christiane M; Gießing, Carsten

    2016-04-01

    Multi-tasking is a familiar situation where behavioral performance is often challenged. To date, fMRI studies investigating the neural underpinning of dual-task interference have mostly relied on local brain activation maps or static brain connectivity networks. Here, based on task fMRI we explored how fluctuations in behavior during concurrent performance of a visuospatial and a speech task relate to alternations in the topology of dynamic brain connectivity networks. We combined a time-resolved functional connectivity and complex network analysis with a sliding window approach applied to the trial by trial behavioral responses to investigate the coupling between dynamic brain networks and dual-task behavior at close temporal proximity. Participants showed fluctuations in their dual-task behavior over time, with the accuracy in the component tasks being statistically independent from one another. On the global level of brain networks we found that dynamic changes of network topology were differentially coupled with the behavior in each component task during the course of dual-tasking. While momentary decrease in the global efficiency of dynamic brain networks correlated with subsequent increase in visuospatial accuracy, better speech performance was preceded by higher global network efficiency and was followed by an increase in between-module connectivity over time. Additionally, dynamic alternations in the modular organization of brain networks at the posterior cingulate cortex were differentially predictive for the visuospatial as compared to the speech accuracy over time. Our results provide the first evidence that, during the course of dual-tasking, each component task is supported by a distinct topological configuration of brain connectivity networks. This finding suggests that the failure of functional brain connectivity networks to adapt to an optimal topology supporting the performance in both component tasks at the same time contributes to the moment to

  5. Cerebrovascular responses of the rat brain to noxious stimuli as examined by functional near-infrared whole brain imaging

    PubMed Central

    He, Ji-Wei; Tian, Fenghua; Liu, Hanli

    2012-01-01

    While near-infrared (NIR) spectroscopy has been increasingly used to detect stimulated brain activities with an advantage of dissociating regional oxy- and deoxyhemoglobin concentrations simultaneously, it has not been utilized much in pain research. Here, we investigated and demonstrated the feasibility of using this technique to obtain whole brain hemodynamics in rats and speculated on the functional relevance of the NIR-based hemodynamic signals during pain processing. NIR signals were emitted and collected using a 26-optodes array on rat's dorsal skull surface after the removal of skin. Following the subcutaneous injection of formalin (50 μl, 3%) into a hindpaw, several isolable brain regions showed hemodynamic changes, including the anterior cingulate cortex, primary/secondary somatosensory cortexes, thalamus, and periaqueductal gray (n = 6). Time courses of hemodynamic changes in respective regions matched with the well-documented biphasic excitatory response. Surprisingly, an atypical pattern (i.e., a decrease in oxyhemoglobin concentration with a concomitant increase in deoxyhemoglobin concentration) was seen in phase II. In a separate group of rats with innocuous brush and noxious pinch of the same area (n = 11), results confirmed that the atypical pattern occurred more likely in the presence of nociception than nonpainful stimulation, suggesting it as a physiological substrate when the brain processes pain. In conclusion, the NIR whole brain imaging provides a useful alternative to study pain in vivo using small-animal models. Our results support the notion that neurovascular response patterns depend on stimuli, bringing attention to the interpretation of vascular-based neuroimaging data in studies of pain. PMID:22378174

  6. Voluntary Alcohol Intake following Blast Exposure in a Rat Model of Mild Traumatic Brain Injury

    PubMed Central

    Lim, Yi Wei; Meyer, Nathan P.; Shah, Alok S.; Budde, Matthew D.; Stemper, Brian D.; Olsen, Christopher M.

    2015-01-01

    Alcoholism is a frequent comorbidity following mild traumatic brain injury (mTBI), even in patients without a previous history of alcohol dependence. Despite this correlational relationship, the extent to which the neurological effects of mTBI contribute to the development of alcoholism is unknown. In this study, we used a rodent blast exposure model to investigate the relationship between mTBI and voluntary alcohol drinking in alcohol naïve rats. We have previously demonstrated in Sprague Dawley rats that blast exposure leads to microstructural abnormalities in the medial prefrontal cortex (mPFC) and other brain regions that progress from four to thirty days. The mPFC is a brain region implicated in alcoholism and drug addiction, although the impact of mTBI on drug reward and addiction using controlled models remains largely unexplored. Alcohol naïve Sprague Dawley rats were subjected to a blast model of mTBI (or sham conditions) and then tested in several common measures of voluntary alcohol intake. In a seven-week intermittent two-bottle choice alcohol drinking test, sham and blast exposed rats had comparable levels of alcohol intake. In a short access test session at the conclusion of the two-bottle test, blast rats fell into a bimodal distribution, and among high intake rats, blast treated animals had significantly elevated intake compared to shams. We found no effect of blast when rats were tested for an alcohol deprivation effect or compulsive drinking in a quinine adulteration test. Throughout the experiment, alcohol drinking was modest in both groups, consistent with other studies using Sprague Dawley rats. In conclusion, blast exposure had a minimal impact on overall alcohol intake in Sprague Dawley rats, although intake was increased in a subpopulation of blast animals in a short access session following intermittent access exposure. PMID:25910266

  7. Establishment and identification of a hypoxia-ischemia brain damage model in neonatal rats

    PubMed Central

    YAO, DAN; ZHANG, WEIRAN; HE, XUE; WANG, JINHU; JIANG, KEWEN; ZHAO, ZHENGYAN

    2016-01-01

    The present study was designed to set up a reliable model of severe hypoxia-ischemia brain damage (HIBD) in neonatal rats and several methods were used to identify whether the model was successful. A total of 40 healthy 7-day-old Sprague-Dawley rats were randomly divided into 2 groups: The sham-surgery group (n=18) and the HIBD model group (n=22). The HIBD model was produced according to the traditional Rice method. The rats were anesthetized with ethyl ether. The left common carotid artery (CCA) was exposed, ligated and cut. Following this, the rats were exposed to hypoxia in a normobaric chamber filled with 8% oxygen and 92% nitrogen for 2 h. In the sham-surgery group, the left CCA was exposed but was not ligated, cut or exposed to hypoxia. The neurobehavioral changes of the rats were observed in the 24 h after HIBD. The brains were collected after 72 h to observe the pathological morphological changes of the brain tissue. The behavioral ability and neurobehavioral changes were studied in each group. The water maze test was used for evaluating the learning-memory ability when the rats were 28 days old. Compared with the sham-surgery group, all the HIBD model rats had a lag of motor development. The rats had evident changes in anatomy and Nissl staining, and cognitive impairment was shown through the result of the water maze. Therefore, the model of HIBD in neonatal rats is feasible and provides a reliable model for subsequent studies. PMID:27073628

  8. Age-Related Differences in the Disposition of Nicotine and Metabolites in Rat Brain and Plasma

    PubMed Central

    2013-01-01

    Introduction: Studies have evaluated the behavioral and neurochemical impact of nicotine administration in rodents. However, the distribution of nicotine and metabolites in rat brain and plasma as a function of age has not been investigated. This is a significant issue because human adolescents have a greater risk for developing nicotine addiction than adults, and reasons underlying this observation have not been fully determined. Thus, in this present study, we evaluated the impact of the transition from adolescence (postnatal day [PND 40]) to adulthood (PND 90) on nicotine distribution in rats. Methods: PND 40, 60, and 90 rats received a single injection of (−) nicotine (0.8mg/kg, subcutaneously). Liquid chromatography tandem-mass spectrometry was used to measure concentration of nicotine and metabolites in selected biological matrices. Results: Nicotine, cotinine, and nornicotine were detected in rat striata and frontal cortex 30min, 1hr, 2hr, and 4hr after a single administration. These and several additional metabolites (nicotine-1′-oxide, cotinine-N-oxide, norcotinine, and trans-3′-hydroxycotinine) were also detected in plasma at these same timepoints. The mean concentration of nicotine in brain and plasma was lower in PND 40 versus PND 90 rats. In contrast, the mean concentration of nornicotine was higher in the plasma and brain of PND 40 versus PND 90 rats. Conclusions: Nicotine and metabolite distribution differs between adolescent and adult rats. These data suggest that adolescent rats metabolize nicotine to some metabolites faster than adult rats. Further studies are needed to investigate the potential correlation between age, drug distribution, and nicotine addiction. PMID:23737496

  9. Effect of cyclosporin on distribution of methotrexate into the brain of rats.

    PubMed

    Ogushi, Naofumi; Sasaki, Kazuaki; Shimoda, Minoru

    2015-09-01

    The effect of the antitumor drug, methotrexate (MTX), which is applied to brain tumors, is restricted by the blood-brain barrier (BBB), which is composed of P-glycoprotein (P-gp) and multidrug resistance associated protein (MRP). We, therefore, studied if a potent P-gp and MRP modulator, cyclosporin A (CysA), can modulate the MTX concentration in the rat brain. If it can, which route is more effective, intravenous or intrathecal? We intravenously or intrathecally administered MTX to rats with or without CysA. After 6 hr, brains and cerebrospinal fluid (CSF) were sampled, and their MTX concentrations were compared. Each MTX concentration was determined by high-performance liquid chromatography with UV detection. CysA had no significant affect on the MTX concentration in the brain or CSF when MTX was intravenously injected. In contrast, when MTX was intrathecally administered, CysA had a larger effect on the MTX concentration in the brain than in the CSF. This indicates CysA potentiated the brain MTX concentration when MTX was intrathecally administered. It is suggested that CysA did not potentiate the distribution of MTX from blood into the brain, but instead potentiated the distribution of MTX from CSF into the brain. Since chemicals in CSF generally diffuse into the brain easily, CysA probably inhibited the excretion of MTX from the brain. This could be caused by inhibition of P-gp or MRP at the BBB. Therefore, CysA can be a useful tool to achieve an appropriate MTX concentration in brain. PMID:25947324

  10. Astrocytic Insulin Signaling Couples Brain Glucose Uptake with Nutrient Availability.

    PubMed

    García-Cáceres, Cristina; Quarta, Carmelo; Varela, Luis; Gao, Yuanqing; Gruber, Tim; Legutko, Beata; Jastroch, Martin; Johansson, Pia; Ninkovic, Jovica; Yi, Chun-Xia; Le Thuc, Ophelia; Szigeti-Buck, Klara; Cai, Weikang; Meyer, Carola W; Pfluger, Paul T; Fernandez, Ana M; Luquet, Serge; Woods, Stephen C; Torres-Alemán, Ignacio; Kahn, C Ronald; Götz, Magdalena; Horvath, Tamas L; Tschöp, Matthias H

    2016-08-11

    We report that astrocytic insulin signaling co-regulates hypothalamic glucose sensing and systemic glucose metabolism. Postnatal ablation of insulin receptors (IRs) in glial fibrillary acidic protein (GFAP)-expressing cells affects hypothalamic astrocyte morphology, mitochondrial function, and circuit connectivity. Accordingly, astrocytic IR ablation reduces glucose-induced activation of hypothalamic pro-opio-melanocortin (POMC) neurons and impairs physiological responses to changes in glucose availability. Hypothalamus-specific knockout of astrocytic IRs, as well as postnatal ablation by targeting glutamate aspartate transporter (GLAST)-expressing cells, replicates such alterations. A normal response to altering directly CNS glucose levels in mice lacking astrocytic IRs indicates a role in glucose transport across the blood-brain barrier (BBB). This was confirmed in vivo in GFAP-IR KO mice by using positron emission tomography and glucose monitoring in cerebral spinal fluid. We conclude that insulin signaling in hypothalamic astrocytes co-controls CNS glucose sensing and systemic glucose metabolism via regulation of glucose uptake across the BBB. PMID:27518562

  11. Neuronal networks and mediators of cortical neurovascular coupling responses in normal and altered brain states.

    PubMed

    Lecrux, C; Hamel, E

    2016-10-01

    Brain imaging techniques that use vascular signals to map changes in neuronal activity, such as blood oxygenation level-dependent functional magnetic resonance imaging, rely on the spatial and temporal coupling between changes in neurophysiology and haemodynamics, known as 'neurovascular coupling (NVC)'. Accordingly, NVC responses, mapped by changes in brain haemodynamics, have been validated for different stimuli under physiological conditions. In the cerebral cortex, the networks of excitatory pyramidal cells and inhibitory interneurons generating the changes in neural activity and the key mediators that signal to the vascular unit have been identified for some incoming afferent pathways. The neural circuits recruited by whisker glutamatergic-, basal forebrain cholinergic- or locus coeruleus noradrenergic pathway stimulation were found to be highly specific and discriminative, particularly when comparing the two modulatory systems to the sensory response. However, it is largely unknown whether or not NVC is still reliable when brain states are altered or in disease conditions. This lack of knowledge is surprising since brain imaging is broadly used in humans and, ultimately, in conditions that deviate from baseline brain function. Using the whisker-to-barrel pathway as a model of NVC, we can interrogate the reliability of NVC under enhanced cholinergic or noradrenergic modulation of cortical circuits that alters brain states.This article is part of the themed issue 'Interpreting BOLD: a dialogue between cognitive and cellular neuroscience'. PMID:27574304

  12. Prostaglandins in the brain of rats given, acutely, and chronically, a hyperthermic dose of met-enkephalin.

    PubMed

    Scoto, G M; Spadaro, C; Spampinato, S; Arrigo-Reina, R; Ferri, S

    1979-01-31

    An enhanced prostaglandinlike activity is shown in homogenates of brain from rats treated intracerebroventricularly with 100 microgram of metenkephalin. The increase is significantly reduced by naloxone pretreatment. A relationship is proposed between generation of prostaglandins in the brain following met-enkephalin administration and hyperthermic effect of the opiatelike factor in the rat. Normalization of prostaglandinlike activity following chronic administration of met-enkephalin in the rat may also account for the development of tolerance to its thermic effect. PMID:106433

  13. Wharton's jelly transplantation improves neurologic function in a rat model of traumatic brain injury

    PubMed Central

    Cheng, Tian; Yang, Bo; Li, Dongpeng; Ma, Shanshan; Tian, Yi; Qu, Ruina; Zhang, Wenjin; Zhang, Yanting; Hu, Kai; Guan, Fangxia; Wang, Jian

    2015-01-01

    Traumatic brain injury (TBI), which can lead to disability, dysfunction, and even death, is a prominent health problem worldwide. Effective therapy for this serious and debilitating condition is needed. Human umbilical cord matrix, known as Wharton's jelly (WJ), provides a natural, interface scaffold that is enriched in mesenchymal stem cells. In this study, we tested the efficacy of WJ tissue transplantation in a weight drop model of TBI in rats. WJ tissue was cultured and transplanted into the injury site 24h after TBI. The modified neurologic severity score, body weight, brain edema, and lesion volume were evaluated at various time points after TBI. Cognitive behavior was assessed by the novel object recognition test and the Morris water maze test. Expression of brain-derived neurotrophic factor (BDNF) in the perilesional brain area was measured at day 14 after TBI. We found that WJ tissue transplantation lessened TBI-induced brain edema (day 3), reduced lesion volume (day 28), improved neurologic function (days 21 to 28), and promoted memory and cognitive recovery. Additionally, expression of BDNF mRNA and protein was higher in WJ tissue-treated rats than in sham-operated or vehicle-treated rats. These data suggest that WJ tissue transplantation can reduce TBI-induced brain injury and may have therapeutic potential for the treatment of TBI. PMID:25638565

  14. Hypoxia Inducible Factor-1 (HIF-1) Independent Microvascular Angiogenesis in the Aged Rat Brain

    PubMed Central

    Ndubuizu, Obinna I.; Tsipis, Constantinos P.; Li, Ang; LaManna, Joseph C.

    2010-01-01

    Angiogenesis is a critical component of mammalian brain adaptation to prolonged hypoxia. Hypoxia-induced angiogenesis is mediated by hypoxia inducible factor-1 (HIF-1) dependent transcriptional activation of growth factors, such as vascular endothelial growth factor (VEGF). Microvascular angiogenesis occurs over a three week period in the rodent brain. We have recently reported that HIF-1α accumulation and transcriptional activation of HIF target genes in the aged cortex of 24 month F344 rats is significantly attenuated during acute hypoxic exposure. In the present study, we show that cortical HIF-1α accumulation and HIF-1 activation remains absent during chronic hypoxic exposure in the aged rat brain (24 month F344). Despite this lack of HIF-1 activation, there is no significant difference in baseline or post-hypoxic brain capillary density counts between the young (3 month F344) and old age groups. VEGF mRNA and protein levels are significantly elevated in the aged cortex despite the lack of HIF-1 activation. Other HIF-independent mediators of hypoxia inducible genes could be involved during chronic hypoxia in the aged brain. PPAR-γ coactivator (PGC)-1α, a known regulator of VEGF gene transcription, is elevated in the young and aged cortex during the chronic hypoxic exposure. Overall, our results suggest a compensatory HIF-1 independent preservation of hypoxic-induced microvascular angiogenesis in the aged rat brain. PMID:20875806

  15. Propressophysin is present in neurones at multiple sites in Wistar and homozygous Brattleboro rat brain.

    PubMed

    van Leeuwen, F W; Caffé, R; van der Sluis, P J; Sluiter, A A; van der Woude, T P; Seidah, N G; Chrétien, M

    1986-07-30

    Vasopressin (VP) is synthesized as propressophysin, containing also neurophysin (NP) and C-terminal glycopeptide (CPP), within the hypothalamo-neurohypophyseal system (HNS). Recently, VP and NP-immunoreactive cells were demonstrated in other rat brain nuclei. Here we report CPP immunoreactivity in perikarya in these nuclei. Within the homozygous Brattleboro rat, known to be deficient in neuronal VP production, no CPP immunoreactivity was seen in these nuclei. However, intense VP and CPP immunoreactivity was present in solitary cells (52.2 +/- 3.3 per rat) and fibres within the HNS. PMID:3742211

  16. Biochemical and histological alterations induced by fluid percussion brain injury in the rat.

    PubMed

    Toulmond, S; Duval, D; Serrano, A; Scatton, B; Benavides, J

    1993-08-20

    In the present study we have characterized the time-course of the histopathological and biochemical alterations resulting from mechanical brain injury caused by lateral fluid percussion centered over the parietal cortex in the rat. The injury device used was an HPLC pump coupled to a solenoid valve which delivered a constant and short lasting (10 ms) impact pressure (1.6 atm). This traumatic procedure resulted in an accumulation of blood in the subarachnoid space and cortical edema at 4-24 h post-trauma. From 4 h after injury, cortical neurons exhibited a pathologic appearance and phagocytic cells invaded the brain parenchyma. At 3 and 7 days post-injury, complete neuronal loss was observed in the parietal cortex around the impact site. In the ipsilateral cortex, the time-course of histologically assessed neuronal loss and phagocytic/glial activation paralleled the time-course of the loss of omega 1-2 (benzodiazepine) sites (a neuronal marker) and of the increase in p sites (peripheral-type benzodiazepine binding sites; a glial/macrophage marker). Neuronal loss and increase in the density of the glial/macrophage biochemical marker were also observed in the hippocampus but not in the contralateral cortex or in other subcortical structures, suggesting a selective vulnerability of the hippocampus to this traumatic procedure. There was a very good spatial correlation between the histological alterations and the changes in the density of the neuronal and glial/macrophage biochemical markers (as assessed by autoradiography). The volume of the lesion, integrated from the surface of the lesion measured at 10 coronal levels cut at a 1 mm interval and stained with haemalum and eosin, represented 32.9 +/- 1.7 mm3.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7691381

  17. Compromised Blood-Brain Barrier Competence in Remote Brain Areas in Ischemic Stroke Rats at Chronic Stage

    PubMed Central

    Garbuzova-Davis, Svitlana; Haller, Edward; Williams, Stephanie N.; Haim, Eithan D.; Tajiri, Naoki; Hernandez-Ontiveros, Diana G.; Frisina-Deyo, Aric; Boffeli, Sean M.; Sanberg, Paul R.; Borlongan, Cesario V.

    2014-01-01

    Stroke is a life threatening disease leading to long-term disability in stroke survivors. Cerebral functional insufficiency in chronic stroke might be due to pathological changes in brain areas remote from initial ischemic lesion, i.e. diaschisis. Previously, we showed that the damaged blood-brain barrier (BBB) was implicated in subacute diaschisis. The present study investigated BBB competence in chronic diaschisis using a transient middle cerebral artery occlusion (tMCAO) rat model. Our results demonstrated significant BBB damage mostly in the ipsilateral striatum and motor cortex in rats at 30 days after tMCAO. The BBB alterations were also determined in the contralateral hemisphere via ultrastructural and immunohistochemical analyses. Major BBB pathological changes in contralateral remote striatum and motor cortex areas included: (1) vacuolated endothelial cells containing large autophagosomes, (2) degenerated pericytes displaying mitochondria with cristae disruption, (3) degenerated astrocytes and perivascular edema, (4) Evans Blue extravasation, and (5) appearance of parenchymal astrogliosis. Importantly, discrete analyses of striatal and motor cortex areas revealed significantly higher autophagosome accumulation in capillaries of ventral striatum and astrogliosis in dorsal striatum in both cerebral hemispheres. These widespread microvascular alterations in ipsilateral and contralateral brain hemispheres suggest persistent and/or continued BBB damage in chronic ischemia. The pathological changes in remote brain areas likely indicate chronic ischemic diaschisis, which should be considered in the development of treatment strategies for stroke. PMID:24610730

  18. Spatial embedding of fMRI for investigating local coupling in human brain

    NASA Astrophysics Data System (ADS)

    Deshpande, Gopikrishna; LaConte, Stephen M.; Peltier, Scott; Hu, Xiaoping

    2005-04-01

    In this paper, we have investigated local spatial couplings in the human brain by applying nonlinear dynamical techniques on fMRI data. We have recorded BOLD-contrast echo-planar fMRI data along with high-resolution T1-weighted anatomical images from the resting brain of healthy human subjects and performed physiological correction on the functional data. The corrected data from resting subjects is spatially embedded into its phase space and the largest Lyapunov exponent of the resulting attractor is calculated and whole slice maps are obtained. In addition, we segment the high-resolution anatomical image and obtain a down sampled mask corresponding to gray and white matter, which is used to obtain mean indices of the exponents for both the tissues separately. The results show the existence of local couplings, its tissue specificity (more local coupling in gray matter than white matter) and dependence on the size of the neighborhood (larger the neighborhood, lesser the coupling). We believe that these techniques capture the information of a nonlinear and evolving system like the brain that may not be evident from static linear methods. The results show that there is evidence of spatio-temporal chaos in the brain, which is a significant finding hitherto not reported in literature to the best of our knowledge. We try to interpret our results from healthy resting subjects based on our knowledge of the native low frequency fluctuations in the resting brain and obtain a better understanding of the local spatial behavior of fMRI. This exploratory study has demonstrated the utility of nonlinear dynamical techniques like spatial embedding in analyzing fMRI data to gain meaningful insights into the working of human brain.

  19. Binding sites for atrial natriuretic factor (ANF) in brain: alterations in Brattleboro rats

    SciTech Connect

    McCarty, R.; Plunkett, L.M.

    1986-12-01

    Binding sites for atrial natriuretic factor (ANF-28) were analyzed in discrete brain areas of Brattleboro rats with hereditary diabetes insipidus and Long-Evans (LE) controls by quantitative autoradiography. The maximum binding capacity (Bmax) and affinity constant (Ka) for /sup 125/I-ANF-28 were elevated significantly in the subfornical organ of Brattleboro rats compared to matched LE controls. In contrast, values for Bmax and Ka for /sup 125/I-ANF-28 binding in choroid plexus and area postrema were similar for rats of the two strains. These findings are consistent with a selective upregulation of ANF-28 binding sites in the subfornical organ of Brattleboro rats which exhibit a profound disturbance in body fluid homeostasis. These alterations in ANF-28 binding sites in the subfornical organ may represent a compensatory response to the absence of vasopressin in the Brattleboro rat.

  20. Gamma Knife irradiation method based on dosimetric controls to target small areas in rat brains

    SciTech Connect

    Constanzo, Julie; Paquette, Benoit; Charest, Gabriel; Masson-Côté, Laurence; Guillot, Mathieu

    2015-05-15

    Purpose: Targeted and whole-brain irradiation in humans can result in significant side effects causing decreased patient quality of life. To adequately investigate structural and functional alterations after stereotactic radiosurgery, preclinical studies are needed. The purpose of this work is to establish a robust standardized method of targeted irradiation on small regions of the rat brain. Methods: Euthanized male Fischer rats were imaged in a stereotactic bed, by computed tomography (CT), to estimate positioning variations relative to the bregma skull reference point. Using a rat brain atlas and the stereotactic bregma coordinates obtained from CT images, different regions of the brain were delimited and a treatment plan was generated. A single isocenter treatment plan delivering ≥100 Gy in 100% of the target volume was produced by Leksell GammaPlan using the 4 mm diameter collimator of sectors 4, 5, 7, and 8 of the Gamma Knife unit. Impact of positioning deviations of the rat brain on dose deposition was simulated by GammaPlan and validated with dosimetric measurements. Results: The authors’ results showed that 90% of the target volume received 100 ± 8 Gy and the maximum of deposited dose was 125 ± 0.7 Gy, which corresponds to an excellent relative standard deviation of 0.6%. This dose deposition calculated with GammaPlan was validated with dosimetric films resulting in a dose-profile agreement within 5%, both in X- and Z-axes. Conclusions: The authors’ results demonstrate the feasibility of standardizing the irradiation procedure of a small volume in the rat brain using a Gamma Knife.

  1. Functional brain activation during retrieval of visceral pain-conditioned passive avoidance in the rat.

    PubMed

    Wang, Zhuo; Bradesi, Sylvie; Charles, Jonathan R; Pang, Raina D; Maarek, Jean-Michel I; Mayer, Emeran A; Holschneider, Daniel P

    2011-12-01

    This study assessed functional brain activation in rats during expectation of visceral pain. Male rats were trained in step-down passive avoidance (PA) for 2 days. Upon stepping down from a platform, conditioned animals received noxious colorectal distension delivered through a colorectal balloon, whereas the balloon in control rats remained uninflated. On day 3, PA behavior was assessed while [(14)C]-iodoantipyrine was infused intravenously, followed by immediate euthanasia. Regional cerebral blood flow-related tissue radioactivity (rCBF) was analyzed by statistical parametric mapping using 3-dimensional brains reconstructed from autoradiographic brain slice images. Associated with retrieved PA behavior, conditioned rats compared with control subjects showed increases in rCBF in sensory (anterior insula, somatosensory cortex), limbic/paralimbic regions (anterior cingulate, prelimbic cortex, amygdala), all regions previously reported to show activation during acute visceral pain. Increases in rCBF were also noted in the dorsal hippocampus, nucleus accumbens, and caudate putamen, regions associated with retrieval of PA. Organization of the underlying brain network was further delineated by functional connectivity analysis. This revealed in conditioned rats a strongly and positively connected corticostriatal cluster (cingulate, prelimbic cortex, caudate putamen). The amygdala and cerebellar hemispheres formed another positively connected cluster, which was negatively connected with the corticostriatal cluster, suggesting corticolimbic modulation. Prelimbic cortex, nucleus accumbens, and anterior insula emerged in conditioned animals as hubs. Our results show that during retrieval of PA, brain areas implicated in PA expression as well as those implicated in acute visceral pain processing were recruited, in line with findings from human brain imaging studies on pain expectation. PMID:21944154

  2. Protective effect of Xingnaojia formulation on rats with brain and liver damage caused by chronic alcoholism

    PubMed Central

    LI, SHUANG; WANG, SU; GUO, ZHI-GANG; HUANG, NING; ZHAO, FAN-RONG; ZHU, MO-LI; MA, LI-JUAN; LIANG, JIN-YING; ZHANG, YU-LIN; HUANG, ZHONG-LIN; WAN, GUANG-RUI

    2015-01-01

    The aim of this study was to observe the effect of a formulation of traditional Chinese medicine extracts known as Xingnaojia (XNJ) on the liver function, learning ability and memory of rats with chronic alcoholism and to verify the mechanism by which it protects the brain and liver. A rat model of chronic alcoholism was used in the study. The spatial learning ability and memory of the rats were tested. The rats were then sacrificed and their brains and hepatic tissues were isolated. The activity of superoxide dismutase (SOD) and levels of glutamate (Glu), N-methyl D-aspartate receptor subtype 2B (NR2B), cyclin-dependent kinase 5 (CDK5) and cannabinoid receptor 1 (CB1) in the hippocampus were analyzed. The ultrastructure of the hepatic tissue was observed by electron microscopy. In addition, the activities of alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) in serum were tested and the levels of low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides (TG) and total cholesterol (TCHOL) were analyzed. XNJ enhanced the learning and memory of rats with chronic alcoholism. Treatment with XNJ increased the activity of SOD, and decreased the expression levels of NR2B mRNA and NR2B, CB1 and CDK5 proteins in the brain tissues compared with those in the model rats. It also increased the activity of ALDH in the serum and liver, decreased the serum levels of LDL, TG and TCHOL and increased the serum level of HDL. These results indicate that XNJ exhibited a protective effect against brain and liver damage in rats with chronic alcoholism. PMID:26640531

  3. Pharmacokinetic Modeling of Non-Linear Brain Distribution of Fluvoxamine in the Rat

    PubMed Central

    Geldof, Marian; Freijer, Jan; van Beijsterveldt, Ludy

    2007-01-01

    Introduction A pharmacokinetic (PK) model is proposed for estimation of total and free brain concentrations of fluvoxamine. Materials and methods Rats with arterial and venous cannulas and a microdialysis probe in the frontal cortex received intravenous infusions of 1, 3.7 or 7.3 mg.kg−1 of fluvoxamine. Analysis With increasing dose a disproportional increase in brain concentrations was observed. The kinetics of brain distribution was estimated by simultaneous analysis of plasma, free brain ECF and total brain tissue concentrations. The PK model consists of three compartments for fluvoxamine concentrations in plasma in combination with a catenary two compartment model for distribution into the brain. In this catenary model, the mass exchange between a shallow perfusion-limited and a deep brain compartment is described by a passive diffusion term and a saturable active efflux term. Results The model resulted in precise estimates of the parameters describing passive influx into (kin) of 0.16 min−1 and efflux from the shallow brain compartment (kout) of 0.019 min−1 and the fluvoxamine concentration at which 50% of the maximum active efflux (C50) is reached of 710 ng.ml−1. The proposed brain distribution model constitutes a basis for precise characterization of the PK–PD correlation of fluvoxamine by taking into account the non-linearity in brain distribution. PMID:17710515

  4. The distribution of intravenous nicardipine in rat brain after subarachnoid hemorrhage

    SciTech Connect

    Tsukahara, T.; Arista, A.; Kassell, N.F. )

    1989-09-01

    The distribution of intravenously injected nicardipine in rat brain was investigated, as well as the influence of subarachnoid hemorrhage on its distribution. Autoradiographic studies demonstrated the accumulation of {sup 3}H-nicardipine only in the ventricles and subarachnoid spaces around pial vessels in normal brains. Thirty minutes after subarachnoid hemorrhage, the concentration of {sup 3}H-nicardipine was higher in the ventricles and in the subarachnoid space than that found in normal brains. It is concluded that nicardipine penetrates into the subarachnoid spaces and ventricles from pial vessels and/or choroid plexus, and that subarachnoid hemorrhage increases the penetration of nicardipine from vessels into the subarachnoid space.

  5. Brain receptors for thyrotropin releasing hormone in morphine tolerant-dependent rats

    SciTech Connect

    Bhargava, H.N.; Das, S.

    1986-03-01

    The effect of chronic treatment of rats with morphine and its subsequent withdrawal on the brain receptors for thyrotropin releasing hormone (TRH) labeled with /sup 3/H-(3MeHis/sup 2/)TRH (MeTRH). Male Sprague Dawley rats were implanted with 4 morphine pellets (each containing 75 mg morphine base) during a 3-day period. Placebo pellet implanted rats served as controls. Both tolerance to and dependence on morphine developed as a result of this procedure. For characterization of brain TRH receptors, the animals were sacrificed 72 h after the implantation of first pellet. In another set of animals the pellets were removed and were sacrificed 24 h later. The binding of /sup 3/H-MeTRH to membranes prepared from brain without the cerebellum was determined. /sup 3/H-MeTRH bound to brain membranes prepared from placebo pellet implanted rats at a single high affinity site with a B/sub max/ value of 33.50 +/- 0.97 fmol/mg protein and a K/sub d/ of 5.18 +/- 0.21 nM. Implantation of morphine pellets did not alter the B/sub max/ value of /sup 3/H-MeTRH but decreased the K/sub d/ value significantly. Abrupt or naloxone precipitated withdrawal of morphine did not alter B/sub max/ or the K/sub d/ values. The binding of /sup 3/H-MeTRH to brain areas was also determined. The results suggest that the development of tolerance to morphine is associated with enhanced sensitivity of brain TRH receptors, however abrupt withdrawal of morphine does not change the characteristics of brain TRH receptors.

  6. HIF prolyl hydroxylase inhibition augments dopamine release in the rat brain in vivo.

    PubMed

    Witten, Louise; Sager, Thomas; Thirstrup, Kenneth; Johansen, Jens Leander; Larsen, Dorrit Bjerg; Montezinho, Liliana P; Mørk, Arne

    2009-05-15

    The transcription factor hypoxia-inducible factor (HIF) is essential for the activation of several genes that promote the survival of cells exposed to oxidative stress. Expression of tyrosine hydroxylase (TH), which is the rate-limiting enzyme in the dopamine (DA) synthesis, is one of the genes that are positively regulated by HIF. Accordingly, HIF induction results in elevated DA release in various cell lines in vitro. HIF prolyl hydroxylase (HPH) is critically involved in the negative regulation of HIF levels. We investigated the in vivo effects of the HPH inhibitor FG0041 on brain DA function in rats by microdialysis in freely moving rats, locomotor activity, and Western blot analysis. Administration of FG0041 (10 mg/kg i.p.), as an acute (single injection), or as subchronic (once daily for 6 days) treatment and cobalt chloride (CoCl2) (60 mg/kg s.c.) potentiated potassium (K+) induced increases in extracellular levels of DA levels in the rat striatum. The increase in extracellular DA of freely moving rats was sought in relationship to locomotor activity in rats. A significant increase in locomotor activity was observed in FG0041-treated rats compared with vehicle on a cocaine challenge. In support of these findings, protein levels of TH in the rat brain stem were increased after treatment with FG0041. These data indicate that FG0041 augments DA function in the rat brain. Inhibition of HPH enhances DA function by increasing DA release, which has implications for the use of HIF induction in the treatment of neurodegenerative diseases. PMID:19156859

  7. Purification to homogeneity of an active opioid receptor from rat brain by affinity chromatography.

    PubMed

    Loukas, S; Mercouris, M; Panetsos, F; Zioudrou, C

    1994-05-10

    Active opioid binding proteins were solubilized from rat brain membranes in high yield with sodium deoxycholate in the presence of NaCl. Purification of opioid binding proteins was accomplished by opioid antagonist affinity chromatography. Chromatography using the delta-opioid antagonist N,N-diallyl-Tyr-D-Leu-Gly-Tyr-Leu attached to omega-aminododecyl-agarose (Affi-G) (procedure A) yielded a partially purified protein that binds selectively the delta-opioid agonist [3H]Tyr-D-Ser-Gly-Phe-Leu-Thr ([3H]DSLET), with a Kd of 19 +/- 3 nM and a Bmax of 5.1 +/- 0.4 nmol/mg of protein. Subsequently, Lens culinaris agglutinin-Sepharose 4B chromatography of the Affi-G eluate resulted in isolation of an electrophoretically homogeneous protein of 58 kDa that binds selectively [3H]DSLET with a Kd of 21 +/- 3 nM and a Bmax of 16.5 +/- 1.0 nmol/mg of protein. Chromatography using the nonselective antagonist 6-aminonaloxone coupled to 6-aminohexanoic acid-Sepharose 4B (Affi-NAL) (procedure B) resulted in isolation of a protein that binds selectively [3H]DSLET with a Kd of 32 +/- 2 nM and a Bmax of 12.4 +/- 0.5 nmol/mg of protein, and NaDodSO4/PAGE revealed a major band of apparent molecular mass 58 kDa. Polyclonal antibodies (Anti-R IgG) raised against the Affi-NAL protein inhibit the specific [3H]DSLET binding to the Affi-NAL eluate and to the solubilized membranes. Moreover, the Anti-R IgG inhibits the specific binding of radiolabeled Tyr-D-Ala-Gly-N-methyl-Phe-Gly-ol (DAMGO; mu-agonist), DSLET (delta-agonist), and naloxone to homogenates of rat brain membranes with equal potency. Furthermore, immunoaffinity chromatography of solubilized membranes resulted in the retention of a major protein of apparent molecular mass 58 kDa. In addition, immunoblotting of solubilized membranes and purified proteins from the Affi-G and Affi-NAL matrices revealed that the Anti-R IgG interacts with a protein of 58 kDa. PMID:8183950

  8. Aqueous Date Fruit Efficiency as Preventing Traumatic Brain Deterioration and Improving Pathological Parameters after Traumatic Brain Injury in Male Rats

    PubMed Central

    Badeli, Hamze; Shahrokhi, Nader; KhoshNazar, Mahdieosadat; Asadi-Shekaari, Majid; Shabani, Mohammad; Eftekhar Vaghefi, Hassan; Khaksari, Mohammad; Basiri, Mohsen

    2016-01-01

    Objective Following traumatic brain injury, disruption of blood-brain-barrier and consequent brain edema are critical events which might lead to increasing intracranial pressure (ICP), and nerve damage. The current study assessed the effects of aqueous date fruit extract (ADFE) on the aforementioned parameters. Materials and Methods In this experimental study, diffused traumatic brain injury (TBI) was generated in adult male rats using Marmarou’s method. Experimental groups include two pre-treatment (oral ADFE, 4 and 8 mL/kg for 14 days), vehicle (distilled water, for 14 days) and sham groups. Brain edema and neuronal injury were measured 72 hours after TBI. Veterinary coma scale (VCS) and ICP were determined at -1, 4, 24, 48 and 72 hours after TBI. Differences among multiple groups were assessed using ANOVA. Turkey’s test was employed for the ANOVA post-hoc analysis. The criterion of statistical significance was sign at P<0.05. Results Brain water content in ADFE-treated groups was decreased in comparison with the TBI+vehicle group. VCS at 24, 48 and 72 hours after TBI showed a significant increase in ADFE groups in comparison with the TBI+vehicle group. ICP at 24, 48 and 72 hours after TBI, was decreased in ADFE groups, compared to the TBI+vehicle. Brain edema, ICP and neuronal injury were also decreased in ADFE group, but VCS was increased following on TBI. Conclusion ADFE pre-treatment demonstrated an efficient method for preventing traumatic brain deterioration and improving pathological parameters after TBI. PMID:27602324

  9. 65zinc uptake from blood into brain and other tissues in the rat

    SciTech Connect

    Pullen, R.G.; Franklin, P.A.; Hall, G.H. )

    1990-10-01

    Zinc is essential for normal growth, development and brain function although little is known about brain zinc homeostasis. Therefore, in this investigation we have studied 65Zn uptake from blood into brain and other tissues and have measured the blood-brain barrier permeability to 65Zn in the anaesthetized rat in vivo. Adult male Wistar rats within the weight range 500-600 g were used. 65ZnCl2 and (125I)albumin, the latter serving as a vascular marker, were injected in a bolus of normal saline I.V. Sequential arterial blood samples were taken during experiments that lasted between 5 min and 5 hr. At termination, samples from the liver, spleen, pancreas, lung, heart, muscle, kidney, bone, testis, ileum, blood cells, csf, and whole brain were taken and analysed for radio-isotope activity. Data have been analysed by Graphical Analysis which suggests 65Zn uptake from blood by all tissues sampled was unidirectional during this experimental period except brain, where at circulation times less than 30 min, 65Zn fluxes were bidirectional. In addition to the blood space, the brain appears to contain a rapidly exchanging compartment(s) for 65Zn of about 4 ml/100g which is not csf.

  10. Changes in localization of synaptophysin following fluid percussion injury in the rat brain.

    PubMed

    Shojo, Hideki; Kibayashi, Kazuhiko

    2006-03-17

    Traumatic brain injuries damage neurons and cause progressing dysfunctions of the brain. Synaptophysin (SYP), a major integral transmembrane protein of synaptic vesicles, provides a molecular marker for the synapse and serves as a functional marker of the brain. This study examined magnitude-dependent changes of SYP in the rat brain 2 days following low, moderate or high fluid percussion injuries and investigated time-dependent changes of SYP in the rat brain with moderate fluid percussion injury 2, 15 and 30 days after trauma using immunohistochemistry and Western blotting. SYP immunoreactivity increased in the lateral cortex and in the subcortical white matter, with increasing magnitude of injury and time after trauma. Increased SYP immunoreactivity was accompanied with degeneration of neuronal cell bodies, their processes and terminals as well as glial cell proliferations. Amounts of SYP measured by Western blotting remained unchanged in brains with moderate fluid percussion within 30 days after trauma. These findings indicate that trauma accumulates SYP at injured sites of neurons without changing SYP contents and that increased SYP immunoreactivity in the cerebral cortex following traumatic injury reflects an inhibition of synaptic vesicle transportation and dysfunction of synapses, thus providing a histological substrate for brain dysfunctions. PMID:16497279

  11. Rapid and widespread distribution of doxycycline in rat brain: a mass spectrometric imaging study.

    PubMed

    Munyeza, Chiedza F; Shobo, Adeola; Baijnath, Sooraj; Bratkowska, Dominika; Naiker, Suhashni; Bester, Linda A; Singh, Sanil D; Maguire, Glenn E M; Kruger, Hendrik G; Naicker, Tricia; Govender, Thavendran

    2016-01-01

    1. The penetration of tetracyclines into the brain has been widely documented. The aim of this work was to develop a matrix assisted laser desorption ionization-mass spectrometry imaging (MALDI MSI) method for the molecular histology of doxycycline (DOX) in the healthy rat brain. 2. The time-dependent distribution was investigated after an i.p. dose of 25 mg/kg at 0, 5, 30, 120, 240, 360 and 480 min postdose. LCMS/MS was used to quantify the drug in plasma and brain homogenates and MALDI MSI was used to determine the distribution of the analyte. 3. Within the first-hour postdose, the drug showed slow accumulation into the plasma and brain tissues. DOX brain concentration gradually increased and reached a peak (Cmax) of 1034.9 ng/mL at 240 min postdose, resulting in a brain plasma ratio of 31%. The images acquired by MSI matched the quantification results and clearly showed drug distribution over the entire rat brain coronal section from 5 min and its slow elimination after 360-min postdose. 4. Our findings confirm that MALDI MSI provides an advanced, label-free and faster alternative technique for xenobiotic distribution such as DOX in tissues, making it an essential drug discovery tool for other possible neuroprotective agents. PMID:26327274

  12. Blood-ocular and blood-brain barrier function in streptozocin-induced diabetes in rats

    SciTech Connect

    Maeepea, O.; Karlsson, C.; Alm, A.

    1984-09-01

    Edetic acid labeled with chromium 51 was injected intravenously in normal rats and in rats with streptozocin-induced diabetes. One hour after the injection the animals were killed and the concentrations of edetic acid 51Cr in vitreous body, retina, and brain were determined. No significant difference was observed between the two groups for either tissue. In a second series, a mixture of tritiated 1-glucose and aminohippuric acid tagged with carbon 14 was injected instead of edetic acid. A substantial accumulation of aminohippuric acid 14C compared with tritiated 1-glucose was observed in the vitreous body and the brain of diabetic rats in comparison with the control group. It is concluded that untreated streptozocin-induced diabetes in rats for one to two weeks will not cause a generalized increase in the permeability of the blood-ocular or the blood-brain barriers, but organic acids may accumulate in the vitreous body as well as in the brain as a consequence of reduced outward transport through these barriers.

  13. ALUMINUM ALTERS CALCIUM TRANSPORT IN PLASMA MEMBRANE AND ENDOPLASMIC RETICULUM FROM RAT BRAIN

    EPA Science Inventory

    Calcium is actively transported into intracellular organelles and out of the cytoplasm by Ca2+/Mg2+-ATPases located in the endoplasmic reticulum and plasma membranes. he effects of aluminum on calcium transport were examined in the adult rat brain. 5Ca-uptake was examined in micr...

  14. Blueberry treatment decreased D-galactose-induced oxidative stress and brain damage in rats.

    PubMed

    Çoban, Jale; Doğan-Ekici, Işın; Aydın, A Fatih; Betül-Kalaz, Esra; Doğru-Abbasoğlu, Semra; Uysal, Müjdat

    2015-06-01

    D-galactose (GAL) causes aging-related changes and oxidative stress in the organism. We investigated the effect of whole fresh blueberry (BB) (Vaccinium corymbosum L.) treatment on oxidative stress in age-related brain damage model. Rats received GAL (300 mg/kg; s.c.; 5 days per week) alone or together with 5 % (BB1) and 10 % (BB2) BB containing chow for two months. Malondialdehyde (MDA),protein carbonyl (PC) and glutathione (GSH) levels, and Cu Zn-superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and glutathione transferase (GST) activities as well as acetylcholinesterase (AChE) activities were determined. Expressions of B cell lymphoma-2 (Bcl-2), Bax and caspase-3 were also evaluated in the brain by immunohistochemistry. MDA and PC levels and AChE activity increased, but GSH levels, SOD and GSH-Px activities decreased together with histopathological structural damage in the brain of GAL-treated rats. BB treatments, especially BB2 reduced MDA and PC levels and AChE activity and elevated GSH levels and GSH-Px activity. BB1 and BB2 treatments diminished apoptosis and ameliorated histopathological findings in the brain of GAL-treated rats. These results indicate that BB partially prevented the shift towards an imbalanced prooxidative status and apoptosis together with histopathological amelioration by acting as an antioxidant (radical scavenger) itself in GAL-treated rats. PMID:25511550

  15. Gaussian beam in two-photon fluorescence imaging of rat brain microvessel

    PubMed Central

    Shi, Lingyan; Rodríguez-Contreras, Adrián; Alfano, Robert R.

    2014-01-01

    Abstract. The critical optical properties of a Gaussian laser beam in two-photon or multiphoton fluorescence imaging, including the beam spot size, depth of focus, and intensity profile, are investigated for spatially locating nanoscale solutes in and surrounding the microvessels of rat brain. PMID:25490048

  16. THYROID INSUFFICIENCY AND GENE EXPRESSION IN DEVELOPING RAT BRAIN: A DOSE RESPONSE STUDY.

    EPA Science Inventory

    Thyroid Insufficiency and Gene Expression in Developing Rat Brain: A Dose Response Study. JE Royland and ME Gilbert, Neurotox. Div., U.S. EPA, RTP, NC, USA. Endocrine disruption is an area of major concern in environmental neurotoxicity. Deficits in thyroid hormone (TH) levels h...

  17. The Physiochemistry of Capped Nanosilver Predicts Its Biological Activity in Rat Brain Endothelial Cells (REBEC4)

    EPA Science Inventory

    The “capping” or coating of nanosilver (nanoAg) extends its potency by limiting its oxidation and aggregation and stabilizing its size and shape. The ability of such coated nanoAg to alter the permeability and activate oxidative stress pathways in rat brain endothelia...

  18. [Sorption of sulfophthaleinic dyes by the brain synaptosomes of rats deprived of parodoxical sleep].

    PubMed

    Nilova, N S

    1984-12-01

    The influence of paradoxical sleep deprivation on sorption of bromphenol blue, bromcresol green and bromthymol blue by rat's brain synaptosomes was studied. Effect of sleep disturbance (increase in the number of dye bindings) was shown to augment with the increase in hydrophobicity of the sulfophtaleinic dye. PMID:6528362

  19. Neuroprotective Effect of Dexmedetomidine on Hyperoxia-Induced Toxicity in the Neonatal Rat Brain

    PubMed Central

    Sifringer, Marco; von Haefen, Clarissa; Krain, Maria; Paeschke, Nadine; Bendix, Ivo; Bührer, Christoph; Spies, Claudia D.; Endesfelder, Stefanie

    2015-01-01

    Dexmedetomidine is a highly selective agonist of α2-receptors with sedative, anxiolytic, analgesic, and anesthetic properties. Neuroprotective effects of dexmedetomidine have been reported in various brain injury models. In the present study, we investigated the effects of dexmedetomidine on neurodegeneration, oxidative stress markers, and inflammation following the induction of hyperoxia in neonatal rats. Six-day-old Wistar rats received different concentrations of dexmedetomidine (1, 5, or 10 µg/kg bodyweight) and were exposed to 80% oxygen for 24 h. Sex-matched littermates kept in room air and injected with normal saline or dexmedetomidine served as controls. Dexmedetomidine pretreatment significantly reduced hyperoxia-induced neurodegeneration in different brain regions of the neonatal rat. In addition, dexmedetomidine restored the reduced/oxidized glutathione ratio and attenuated the levels of malondialdehyde, a marker of lipid peroxidation, after exposure to high oxygen concentration. Moreover, administration of dexmedetomidine induced downregulation of IL-1β on mRNA and protein level in the developing rat brain. Dexmedetomidine provides protections against toxic oxygen induced neonatal brain injury which is likely associated with oxidative stress signaling and inflammatory cytokines. Our results suggest that dexmedetomidine may have a therapeutic potential since oxygen administration to neonates is sometimes inevitable. PMID:25653737

  20. Expression of beta 3-adrenoceptor mRNA in rat brain.

    PubMed Central

    Summers, R. J.; Papaioannou, M.; Harris, S.; Evans, B. A.

    1995-01-01

    The reverse transcription/polymerase chain reaction was used to demonstrate beta 3-adrenoceptor mRNA in rat brain regions. Levels were highest in hippocampus, cerebral cortex and striatum and lower in hypothalamus, brainstem and cerebellum. Images Figure 1 PMID:8590968

  1. CONCENTRATION OF GLIAL FIBRILLARY ACIDIC PROTEIN INCREASES WITH AGE IN THE MOUSE AND RAT BRAIN

    EPA Science Inventory

    The role of aging in the expression of the astrocyte protein, glial fibrillary acidic protein (GFAP), was examined. n both mice and rats the concentration of GFAP increased throughout the brain as a function of aging. he largest increase (2-fold) was observed in striatum for both...

  2. PRENATAL EXPOSURE TO CHLORPYRIFOS ALTERS NEUROTROPHIN IMMUNOREACTIVITY AND APOPTOSIS IN RAT BRAIN.

    EPA Science Inventory

    In the present study, the effects of the organophosphate pesticide chlorpyrifos [CPF; O,O'diethyl O-3,5,6-trichloro-2-pyridyl) phosphorothionate] on the regional distribution of three neurotrophic factors and on levels of apoptosis in gestational rat brain were characterized. P...

  3. The primary structure of rat brain (cytoplasmic) dynein heavy chain, a cytoplasmic motor enzyme.

    PubMed Central

    Zhang, Z; Tanaka, Y; Nonaka, S; Aizawa, H; Kawasaki, H; Nakata, T; Hirokawa, N

    1993-01-01

    Overlapping cDNA clones encoding the heavy chain of rat brain cytoplasmic dynein have been isolated. The isolated cDNA clones contain an open reading frame of 13,932 bp encoding 4644 aa (M(r), 532,213). The deduced protein sequence of the heavy chain of rat brain dynein shows significant similarity to sea urchin flagellar beta-dynein (27.0% identical) and to Dictyostelium cytoplasmic dynein (53.5% identical) throughout the entire sequence. The heavy chain of rat brain (cytoplasmic) dynein contains four putative nucleotide-binding consensus sequences [GX4GK(T/S)] in the central one-third region that are highly similar to those of sea urchin and Dictyostelium dyneins. The N-terminal one-third of the heavy chain of rat brain (cytoplasmic) dynein shows high similarity (43.8% identical) to that of Dictyostelium cytoplasmic dynein but poor similarity (19.4% identical) to that of sea urchin flagellar dynein. These results suggested that the C-terminal two-thirds of the dynein molecule is conserved and plays an essential role in microtubule-dependent motility activity, whereas the N-terminal regions are different between cytoplasmic and flagellar dyneins. Images Fig. 1 PMID:7690137

  4. Brain SERT Expression of Male Rats Is Reduced by Aging and Increased by Testosterone Restitution

    PubMed Central

    Herrera-Pérez, José Jaime; Fernández-Guasti, Alonso; Martínez-Mota, Lucía

    2013-01-01

    In preclinical and clinical studies aging has been associated with a deteriorated response to antidepressant treatment. We hypothesize that such impairment is explained by an age-related decrease in brain serotonin transporter (SERT) expression associated with low testosterone (T) levels. The objectives of this study were to establish (1) if brain SERT expression is reduced by aging and (2) if the SERT expression in middle-aged rats is increased by T-restitution. Intact young rats (3–5 months) and gonad-intact middle-aged rats with or without T-restitution were used. The identification of the brain SERT expression was done by immunofluorescence in prefrontal cortex, lateral septum, hippocampus, and raphe nuclei. An age-dependent reduction of SERT expression was observed in all brain regions examined, while T-restitution recovered the SERT expression only in the dorsal raphe of middle-aged rats. This last action seems relevant since dorsal raphe plays an important role in the antidepressant action of selective serotonin reuptake inhibitors. All data suggest that this mechanism accounts for the T-replacement usefulness to improve the response to antidepressants in the aged population. PMID:26317087

  5. Aging-Dependent Changes in the Radiation Response of the Adult Rat Brain

    SciTech Connect

    Schindler, Matthew K. Forbes, M. Elizabeth; Robbins, Mike E.; Riddle, David R.

    2008-03-01

    Purpose: To assess the impact of aging on the radiation response in the adult rat brain. Methods and Materials: Male rats 8, 18, or 28 months of age received a single 10-Gy dose of whole-brain irradiation (WBI). The hippocampal dentate gyrus was analyzed 1 and 10 weeks later for sensitive neurobiologic markers associated with radiation-induced damage: changes in density of proliferating cells, immature neurons, total microglia, and activated microglia. Results: A significant decrease in basal levels of proliferating cells and immature neurons and increased microglial activation occurred with normal aging. The WBI induced a transient increase in proliferation that was greater in older animals. This proliferation response did not increase the number of immature neurons, which decreased after WBI in young rats, but not in old rats. Total microglial numbers decreased after WBI at all ages, but microglial activation increased markedly, particularly in older animals. Conclusions: Age is an important factor to consider when investigating the radiation response of the brain. In contrast to young adults, older rats show no sustained decrease in number of immature neurons after WBI, but have a greater inflammatory response. The latter may have an enhanced role in the development of radiation-induced cognitive dysfunction in older individuals.

  6. Acute effect of aspartame-induced oxidative stress in Wistar albino rat brain

    PubMed Central

    Ashok, Iyaswamy; Sheeladevi, Rathinasamy; Wankhar, Dapkupar

    2015-01-01

    Abstract The present study was carried out to investigate the acute effect of aspartame on oxidative stress in the Wistar albino rat brain. We sought to investigate whether acute administration of aspartame (75 mg/kg) could release methanol and induce oxidative stress in the rat brain 24 hours after administration. To mimic human methanol metabolism, methotrexate treated rats were used to study aspartame effects. Wistar strain male albino rats were administered with aspartame orally as a single dose and studied along with controls and methotrexate treated controls. Blood methanol and formate level were estimated after 24 hours and rats were sacrificed and free radical changes were observed in discrete regions by assessing the scavenging enzymes, reduce dglutathione (GSH), lipid peroxidation and protein thiol levels. There was a significant increase in lipid peroxidation levels, superoxide dismutase activity (SOD), glutathione peroxidase levels (GPx), and catalase activity (CAT) with a significant decrease in GSH and protein thiol. Aspartame exposure resulted in detectable methanol even after 24 hours. Methanol and its metabolites may be responsible for the generation of oxidative stress in brain regions. The observed alteration in aspartame fed animals may be due to its metabolite methanol and elevated formate. The elevated free radicals due to methanol induced oxidative stress. PMID:26445572

  7. Acute effect of aspartame-induced oxidative stress in Wistar albino rat brain.

    PubMed

    Ashok, Iyaswamy; Sheeladevi, Rathinasamy; Wankhar, Dapkupar

    2015-09-01

    The present study was carried out to investigate the acute effect of aspartame on oxidative stress in the Wistar albino rat brain. We sought to investigate whether acute administration of aspartame (75 mg/kg) could release methanol and induce oxidative stress in the rat brain 24 hours after administration. To mimic human methanol metabolism, methotrexate treated rats were used to study aspartame effects. Wistar strain male albino rats were administered with aspartame orally as a single dose and studied along with controls and methotrexate treated controls. Blood methanol and formate level were estimated after 24 hours and rats were sacrificed and free radical changes were observed in discrete regions by assessing the scavenging enzymes, reduce dglutathione (GSH), lipid peroxidation and protein thiol levels. There was a significant increase in lipid peroxidation levels, superoxide dismutase activity (SOD), glutathione peroxidase levels (GPx), and catalase activity (CAT) with a significant decrease in GSH and protein thiol. Aspartame exposure resulted in detectable methanol even after 24 hours. Methanol and its metabolites may be responsible for the generation of oxidative stress in brain regions. The observed alteration in aspartame fed animals may be due to its metabolite methanol and elevated formate. The elevated free radicals due to methanol induced oxidative stress. PMID:26445572

  8. Testosterone replacement attenuates cognitive decline in testosterone-deprived lean rats, but not in obese rats, by mitigating brain oxidative stress.

    PubMed

    Pintana, Hiranya; Pongkan, Wanpitak; Pratchayasakul, Wasana; Chattipakorn, Nipon; Chattipakorn, Siriporn C

    2015-10-01

    Testosterone replacement improves metabolic parameters and cognitive function in hypogonadism. However, the effects of testosterone therapy on cognition in obese condition with testosterone deprivation have not been investigated. We hypothesized that testosterone replacement improves cognitive function in testosterone-deprived obese rats by restoring brain insulin sensitivity, brain mitochondrial function, and hippocampal synaptic plasticity. Thirty male Wistar rats had either a bilateral orchiectomy (ORX: O, n = 24) or a sham operation (S, n = 6). ORX rats were further divided into two groups fed with either a normal diet (NDO) or a high-fat diet (HFO) for 12 weeks. Then, ORX rats in each dietary group were divided into two subgroups (n = 6/subgroup) and were given either castor oil or testosterone (2 mg/kg/day, s.c.) for 4 weeks. At the end of this protocol, cognitive function, metabolic parameters, brain insulin sensitivity, hippocampal synaptic plasticity, and brain mitochondrial function were determined. We found that testosterone replacement increased peripheral insulin sensitivity, decreased circulation and brain oxidative stress levels, and attenuated brain mitochondrial ROS production in HFO rats. However, testosterone failed to restore hippocampal synaptic plasticity and cognitive function in HFO rats. In contrast, in NDO rats, testosterone decreased circulation and brain oxidative stress levels, attenuated brain mitochondrial ROS production, and restored hippocampal synaptic plasticity as well as cognitive function. These findings suggest that testosterone replacement improved peripheral insulin sensitivity and decreased oxidative stress levels, but failed to restore hippocampal synaptic plasticity and cognitive function in testosterone-deprived obese rats. However, it provided beneficial effects in reversing cognitive impairment in testosterone-deprived non-obese rats. PMID:26277724

  9. Antenatal taurine supplementation increases taurine content in intrauterine growth restricted fetal rat brain tissue.

    PubMed

    Li, Fang; Teng, Hui-Yun; Liu, Jing; Wang, Hua-Wei; Zeng, Li; Zhao, Li-Fang

    2014-09-01

    This study aimed to determine the influence of antenatal taurine supplementation on taurine content in the brains of fetal rats with intrauterine growth restriction (IUGR). Experiments were performed at the Central Laboratory of Bayi Children's Hospital Affiliated to Beijing Military General Hospital in China from January to June 2013. Fifteen pregnant rats were randomly divided into three groups: normal controls, an IUGR group and an IUGR + antenatal taurine supplement group (Taurine group) (n = 5). The IUGR model was induced using a low-protein diet throughout gestation. Rats in the taurine group were fed a diet supplemented with 300 mg/kg/day taurine for 12 days after conception until natural delivery. Two fetal rats were randomly selected in every litter, and taurine levels in the brains of rats were detected using high-performance liquid chromatography-mass spectrometry. Results showed that (1) the mean body weight of the fetal rats in the normal control, IUGR and IUGR + antenatal taurine supplement groups was 6.619 ± 0.4132, 4.509 ± 0.454, and 5.176 ± 0.436 g (F = 429.818, P < 0.01), respectively, and (2) that taurine levels in the brains of the fetal rats in the normal control, IUGR and taurine groups were (2.399 ± 0.134) × 10(5), (1.881 ± 0.166) × 10(5) and (2.170 ± 0.191) × 10(5) μg/g (F = 24.828, P < 0.01), respectively. Overall, our results indicated that taurine levels in IUGR fetal rat brains were lower than in the control animals, and that antenatal taurine supplementation could significantly increase taurine levels in the brains of fetal rats with IUGR. PMID:24676564

  10. Influence of exercise training on ischemic brain injury in type 1 diabetic rats.

    PubMed

    Arrick, Denise M; Sun, Hong; Mayhan, William G

    2012-10-01

    While exercise training (ExT) appears to influence cerebrovascular function during type 1 diabetes (T1D), it is not clear whether this beneficial effect extends to protecting the brain from ischemia-induced brain injury. Thus our goal was to examine whether modest ExT could influence transient focal ischemia-induced brain injury along with nitric oxide synthase (NOS)-dependent dilation of cerebral (pial) arterioles during T1D. Sprague-Dawley rats were divided into four groups: nondiabetic sedentary, nondiabetic ExT, diabetic (streptozotocin; 50 mg/kg ip) sedentary, and diabetic ExT. In the first series of studies, we measured infarct volume in all groups of rats following right MCA occlusion for 2 h, followed by 24 h of reperfusion. In a second series of studies, a craniotomy was performed over the parietal cortex, and we measured responses of pial arterioles to an endothelial NOS (eNOS)-dependent, a neuronal NOS (nNOS)-dependent, and a NOS-independent agonist in all groups of rats. We found that sedentary diabetic rats had significantly larger total, cortical, and subcortical infarct volumes following ischemia-reperfusion than sedentary nondiabetic, nondiabetic ExT, and diabetic ExT rats. Infarct volumes were similar in sedentary nondiabetic, ExT nondiabetic, and ExT diabetic rats. In contrast, ExT did not alter infarct size in nondiabetic compared with sedentary nondiabetic rats. In addition, ExT diabetic rats had impaired eNOS- and nNOS-dependent, but not NOS-independent, vasodilation that was restored by ExT. Thus ExT of T1D rats lessened ischemic brain injury following middle cerebral artery occlusion and restored impaired eNOS- and nNOS-dependent vascular function. Since the incidence of ischemic stroke is increased during T1D, we suggest that our finding are significant in that modest ExT may be a viable preventative therapeutic approach to lessen ischemia-induced brain injury that may occur in T1D subjects. PMID:22858624

  11. Transcriptome Sequencing of Gene Expression in the Brain of the HIV-1 Transgenic Rat

    PubMed Central

    Li, Ming D.; Cao, Junran; Wang, Shaolin; Wang, Ju; Sarkar, Sraboni; Vigorito, Michael; Ma, Jennie Z.; Chang, Sulie L.

    2013-01-01

    The noninfectious HIV-1 transgenic (HIV-1Tg) rat was developed as a model of AIDs-related pathology and immune dysfunction by manipulation of a noninfectious HIV-1gag-pol virus with a deleted 3-kb SphI-MscI fragment containing the 3′ -region of gag and the 5′ region of pol into F344 rats. Our previous studies revealed significant behavioral differences between HIV-1Tg and F344 control rats in their performance in the Morris water maze and responses to psychostimulants. However, the molecular mechanisms underlying these behavioral differences remain largely unknown. The primary goal of this study was to identify differentially expressed genes and enriched pathways affected by the gag-pol-deleted HIV-1 genome. Using RNA deep sequencing, we sequenced RNA transcripts in the prefrontal cortex, hippocampus, and striatum of HIV-1Tg and F344 rats. A total of 72 RNA samples were analyzed (i.e., 12 animals per group × 2 strains × 3 brain regions). Following deep-sequencing analysis of 50-bp paired-end reads of RNA-Seq, we used Bowtie/Tophat/Cufflinks suites to align these reads into transcripts based on the Rn4 rat reference genome and to measure the relative abundance of each transcript. Statistical analyses on each brain region in the two strains revealed that immune response- and neurotransmission-related pathways were altered in the HIV-1Tg rats, with brain region differences. Other neuronal survival-related pathways, including those encoding myelin proteins, growth factors, and translation regulators, were altered in the HIV-1Tg rats in a brain region-dependent manner. This study is the first deep-sequencing analysis of RNA transcripts associated the HIV-1Tg rat. Considering the functions of the pathways and brain regions examined in this study, our findings of abnormal gene expression patterns in HIV-1Tg rats suggest mechanisms underlying the deficits in learning and memory and vulnerability to drug addiction and other psychiatric disorders observed in HIV

  12. Biochemical effect of a ketogenic diet on the brains of obese adult rats.

    PubMed

    Mohamed, Hoda E; El-Swefy, Sahar E; Rashed, Leila A; Abd El-Latif, Sally K

    2010-07-01

    Excess weight, particularly abdominal obesity, can cause or exacerbate cardiovascular and metabolic disease. Obesity is also a proven risk factor for Alzheimer's disease (AD). Various studies have demonstrated the beneficial effects of a ketogenic diet (KD) in weight reduction and in modifying the disease activity of neurodegenerative disorders, including AD. Therefore, in this study we examined the metabolic and neurodegenerative changes associated with obesity and the possible neuroprotective effects of a KD in obese adult rats. Compared with obese rats fed a control diet, obese rats fed a KD showed significant weight loss, improvement in lipid profiles and insulin resistance, and upregulation of adiponectin mRNA expression in adipose tissue. In addition, the KD triggered significant downregulation of brain amyloid protein precursor, apolipoprotein E and caspase-3 mRNA expression, and improvement of brain oxidative stress responses. These findings suggest that a KD has anti-obesity and neuroprotective effects. PMID:20395146

  13. Effect of mosquito mats (pyrethroid-based) vapor inhalation on rat brain cytochrome P450s.

    PubMed

    Vences-Mejía, Araceli; Gómez-Garduño, Josefina; Caballero-Ortega, Heriberto; Dorado-González, Víctor; Nosti-Palacios, Rosario; Labra-Ruíz, Norma; Espinosa-Aguirre, J Javier

    2012-01-01

    The effect of transfluthrin (TF) or D-allethrin (DA) pyrethroid (PYR) vapors, often contained as main ingredients in two commercially available mosquito repellent mats, on cytochrome P450 (CYP) enzymes of rat brain and liver was assessed. Immunodetection of CYP2E1 and CYP3A2 proteins revealed their induction in cerebrum and cerebellum, but not in liver microsomes of rats exposed by inhalation to TF or DA. This overexpression of proteins correlated with an increase of their catalytic activities. The specifically increased expression of CYP isoenzymes, due to PYR exposure in the rat brain, could perturb the normal metabolism of endogenous and xenobiotic compounds and leads to increased risks of neurotoxicity by bioactivation, lipid peroxidation and DNA damage. PMID:22080754

  14. Safety evaluation of mercury based Ayurvedic formulation (Sidh Makardhwaj) on brain cerebrum, liver & kidney in rats

    PubMed Central

    Kumar, Gajendra; Srivastava, Amita; Sharma, Surinder Kumar; Gupta, Yogendra Kumar

    2014-01-01

    Background & objectives: Sidh Makardhwaj (SM) is a mercury based Ayurvedic formulation used in rheumatoid arthritis and neurological disorders. However, toxicity concerns due to mercury content are often raised. Therefore, the present study was carried out to evaluate the effect of SM on brain cerebrum, liver and kidney in rats. Methods: Graded doses of SM (10, 50, 100 mg/kg), mercuric chloride (1 mg/kg) and normal saline were administered orally to male Wistar rats for 28 days. Behavioural parameters were assessed on days 1, 7, 14 and 28 using Morris water maze, passive avoidance, elevated plus maze and rota rod. Liver and kidney function tests were done on day 28. Animals were sacrificed and brain cerebrum acetylcholinesterase activity, levels of malondialdehyde (MDA), reduced glutathione (GSH) in brain cerebrum, liver, kidney were estimated. The levels of mercury in brain cerebrum, liver and kidney were estimated and histopathology of these tissues was also performed. Results: SM in the doses used did not cause significant change in neurobehavioural parameters, brain cerebrum AChE activity, liver (ALT, AST, ALP bilirubin) and kidney (serum urea and creatinine) function tests as compared to control. The levels of mercury in brain cerebrum, liver, and kidney were found to be raised in dose dependent manner. However, the levels of MDA and GSH in these tissues did not show significant changes at doses of 10 and 50 mg/kg. Also, there was no histopathological change in cytoarchitecture of brain cerebrum, liver, and kidney tissues at doses of 10 and 50 mg/kg. Interpretation & conclusions: The findings of the present study suggest that Sidh Makardhwaj upto five times the equivalent human dose administered for 28 days did not show any toxicological effects on rat brain cerebrum, liver and kidney. PMID:24927349

  15. Differential metabolism of 4-hydroxynonenal in liver, lung and brain of mice and rats

    SciTech Connect

    Zheng, Ruijin; Dragomir, Ana-Cristina; Mishin, Vladimir; Richardson, Jason R.; Heck, Diane E.; Laskin, Debra L.; Laskin, Jeffrey D.

    2014-08-15

    The lipid peroxidation end-product 4-hydroxynonenal (4-HNE) is generated in tissues during oxidative stress. As a reactive aldehyde, it forms Michael adducts with nucleophiles, a process that disrupts cellular functioning. Liver, lung and brain are highly sensitive to xenobiotic-induced oxidative stress and readily generate 4-HNE. In the present studies, we compared 4-HNE metabolism in these tissues, a process that protects against tissue injury. 4-HNE was degraded slowly in total homogenates and S9 fractions of mouse liver, lung and brain. In liver, but not lung or brain, NAD(P)+ and NAD(P)H markedly stimulated 4-HNE metabolism. Similar results were observed in rat S9 fractions from these tissues. In liver, lung and brain S9 fractions, 4-HNE formed protein adducts. When NADH was used to stimulate 4-HNE metabolism, the formation of protein adducts was suppressed in liver, but not lung or brain. In both mouse and rat tissues, 4-HNE was also metabolized by glutathione S-transferases. The greatest activity was noted in livers of mice and in lungs of rats; relatively low glutathione S-transferase activity was detected in brain. In mouse hepatocytes, 4-HNE was rapidly taken up and metabolized. Simultaneously, 4-HNE-protein adducts were formed, suggesting that 4-HNE metabolism in intact cells does not prevent protein modifications. These data demonstrate that, in contrast to liver, lung and brain have a limited capacity to metabolize 4-HNE. The persistence of 4-HNE in these tissues may increase the likelihood of tissue injury during oxidative stress. - Highlights: • Lipid peroxidation generates 4-hydroxynonenal, a highly reactive aldehyde. • Rodent liver, but not lung or brain, is efficient in degrading 4-hydroxynonenal. • 4-hydroxynonenal persists in tissues with low metabolism, causing tissue damage.

  16. Metabolism of AM404 From Acetaminophen at Human Therapeutic Dosages in the Rat Brain

    PubMed Central

    Muramatsu, Shun; Shiraishi, Seiji; Miyano, Kanako; Sudo, Yuka; Toda, Akiko; Mogi, Masayuki; Hara, Mayumi; Yokoyama, Akinobu; Kawasaki, Yoshihiko; Taniguchi, Mikio; Uezono, Yasuhito

    2016-01-01

    Background: Acetaminophen, an analgesic and antipyretic drug, has been used clinically for more than a century. Previous studies showed that acetaminophen undergoes metabolic transformations to form an analgesic compound, N-(4-hydroxyphenyl) arachidonamide (AM404), in the rodent brain. However, these studies were performed with higher concentrations of acetaminophen than are used in humans. Objectives: The aim of the present study was to examine the metabolism of AM404 from acetaminophen in the rat brain at a concentration of 20 mg/kg, which is used in therapeutic practice in humans, and to compare the pharmacokinetics between them. Materials and Methods: We used rat brains to investigate the metabolism of AM404 from acetaminophen at concentrations (20 mg/kg) used in humans. In addition, we determined the mean pharmacokinetic parameters for acetaminophen and its metabolites, including AM404. Results: The maximum plasma concentrations of acetaminophen and AM404 in the rat brain were 15.8 µg/g and 150 pg/g, respectively, with corresponding AUC0-2h values of 8.96 μg hour/g and 117 pg hour/g. The tmax for both acetaminophen and AM404 was 0.25 hour. Conclusions: These data suggest that AM404’s concentration-time profile in the brain is similar to those of acetaminophen and its other metabolites. Measurement of blood acetaminophen concentration seems to reflect the concentration of the prospective bioactive substance, AM404. PMID:27110534

  17. Interaction of ethanol and microwaves on the blood-brain barrier of rats

    SciTech Connect

    Neilly, J.P.; Lin, J.C.

    1986-01-01

    The combined effects of ethanol and microwaves on the permeation of Evans blue dye through the mammalian blood-brain barrier was studied in male Wistar rats. Anesthetized rats were infused through a cannula in the left femoral vein with 0.1, 0.3, 0.5 or 0.7 grams of absolute ethanol per kilogram of body mass. A control group was given 0.7 g/kg of isotonic saline. The left hemisphere of the brain was irradiated by 3.15-GHz microwave energy at 3.0 W/cm2 rms for 15 min. The rat's rectal temperature was maintained at 37.0 degrees C. Immediately after irradiation, 2% Evans blue dye in saline (2.0 ml/kg body mass) was injected through the cannula. The results show that as the quantity of alcohol was increased, the degree of staining was decreased or eliminated. The temperature of the irradiated area of the brain increased for the first 4 to 5 minutes of irradiation and then stabilized for the remainder of the irradiation period. The steady-state temperature was highest in animals receiving saline or the smallest dose of alcohol. As the quantity of alcohol was increased, the steady-state temperature was reduced. These results indicate that ethanol inhibits microwave-induced permeation of the blood-brain barrier through reduced heating of the brain.

  18. Effect of Pentoxifylline on Ischemia- induced Brain Damage and Spatial Memory Impairment in Rat

    PubMed Central

    Movassaghi, Shabnam; Nadia Sharifi, Zahra; Soleimani, Mansooreh; Joghataii, Mohammad Taghi; Hashemi, Mehrdad; Shafaroodi, Hamed; Mehdizadeh, Mehdi

    2012-01-01

    Objective(s) The brief interruption of cerebral blood flow causes permanent brain damage and behavioral dysfunction. The hippocampus is highly vulnerable to ischemic insults, particularly the CA1 pyramidal cell layer. There is no effective pharmacological strategy for improving brain tissue damage induced by cerebral ischemia. Previous studies reported that pentoxifylline (PTX) has a neuroprotective effect on brain trauma. The possible neuroprotector effects of PTX on behavioral deficit were studied in male Wistar rats subjected to a model of transient global brain ischemia. Materials and Methods Animals (n= 32) were assigned to control, sham-operated, vehicle, and PTX- treated (200 mg/kg IP) groups. PTX administered at 1hr before and 3 hr after ischemia. Global cerebral ischemia was induced by bilateral common carotid artery occlusion, followed by reperfusion. Results Morris Water maze testing revealed that PTX administration in cerebral ischemia significantly improved hippocampal-dependent memory and cognitive spatial abilities after reperfusion as compared to sham-operated and vehicle-treated animals. After the behavioral test, the rats were sacrificed and brain sections were stained with Nissl staining. There were no significant differences between number of pyramidal cells in both control and PTX groups. Conclusion Our study demonstrated that pentoxifylline had a protective effect on rats with transient global ischemia and could reduce cognitive impairment. PMID:23493977

  19. Propofol anesthesia reduces Lempel-Ziv complexity of spontaneous brain activity in rats.

    PubMed

    Hudetz, Anthony G; Liu, Xiping; Pillay, Siveshigan; Boly, Melanie; Tononi, Giulio

    2016-08-15

    Consciousness is thought to scale with brain complexity, and it may be diminished in anesthesia. Lempel-Ziv complexity (LZC) of field potentials has been shown to be a promising measure of the level of consciousness in anesthetized human subjects, neurological patients, and across the sleep-wake states in rats. Whether this relationship holds for intrinsic networks obtained by functional brain imaging has not been tested. To fill this gap of knowledge, we estimated LZC from large-scale dynamic analysis of functional magnetic resonance images (fMRI) in conscious sedated and unconscious anesthetized rats. Blood oxygen dependent (BOLD) signals were obtained from 30-min whole-brain resting-state scans while the anesthetic propofol was infused intravenously at constant infusion rates of 20mg/kg/h (conscious sedated) and 40mg/kg/h (unconscious). Dynamic brain networks were defined at voxel level by sliding window analysis of regional homogeneity (ReHo) of the BOLD signal. From scans performed at low to high propofol dose, the LZC was significantly reduced by 110%. The results suggest that the difference in LZC between conscious sedated and anesthetized unconscious subjects is conserved in rats and this effect is detectable in large-scale brain network obtained from fMRI. PMID:27291459

  20. Effect of rapid correction of hyponatremia on the blood-brain barrier of rats.

    PubMed

    Adler, S; Verbalis, J G; Williams, D

    1995-05-01

    Brain demyelination sometimes follows rapid correction of hyponatremia, especially if the hyponatremia is chronic. During correction brain water decreases and the brain shrinks. The present study examined whether such shrinkage might be sufficient to disrupt the tight junctions of the blood-brain barrier. Barrier intactness was evaluated using magnetic resonance imaging and intravenous gadolinium contrast administration. Hypertonic saline infusion rapidly increased the plasma sodium concentration and caused barrier disruption more frequently in chronic than in acute hyponatremic rats. Similar increases in plasma sodium concentration did not disrupt the barrier in normonatremic rats. The disruption appeared to be due to altered plasma osmolality since infusion of hypertonic mannitol, which raised plasma osmolality without changing the plasma sodium concentration, disrupted the barrier in hyponatremic but not normonatremic rats. Moreover, the osmotic threshold for barrier disruption was lowest in chronic hyponatremia, intermediate in acute hyponatremia, and highest in normonatremia. The greater susceptibility to osmotic disruption in chronic hyponatremia suggests that blood-brain barrier disruption may play a significant role in causing the demyelination sometimes found following too rapid correction of hyponatremia, possibly through exposure of oligodendrocytes to plasma macromolecules such as complement. PMID:7648255

  1. Acute effects of oral or parenteral aspartame on catecholamine metabolism in various regions of rat brain.

    PubMed

    Yokogoshi, H; Wurtman, R J

    1986-03-01

    Hypertensive (SHR) and nonhypertensive [Wistar-Kyoto (WKY); Sprague-Dawley (SD)] strains of rats received the dipeptide sweetener aspartame (200 mg/kg) or, as a positive control, tyrosine (200 mg/kg) by gavage or parenterally, after a brief (2-h) fast. Two hours later, compared with those of saline controls brain levels of the norepinephrine metabolite 3-methoxy-4-hydroxyphenylethylethyleneglycol (MHPG) sulfate were significantly higher in the hypothalamus (WKY), locus coeruleus (SD and SHR) and brain stem (SHR) in tyrosine-treated animals, and in the locus coeruleus (SD) of those given aspartame. Brain norepinephrine levels were also higher, compared with those of saline-treated control rats, in the cerebral cortex (SD and SHR), amygdala (SD) and locus coeruleus (WKY) after tyrosine administration, and in the amygdala (SD) and cerebral cortex (SHR) after aspartame administration. In another study, oral aspartame was found to be at least as effective as the parenterally administered sweetener in raising regional brain levels of tyrosine or MHPG sulfate (i.e., compared with corresponding levels in saline-treated rats). Animals receiving oral aspartame also exhibited higher plasma tyrosine and phenylalanine ratios (i.e., the ratios of their plasma concentrations to the summed concentrations of other large neutral amino acids that compete with them for uptake into the brain), than animals receiving saline. PMID:3950762

  2. Uptake and biodistribution of rizatriptan to blood and brain following different routes of administration in rats.

    PubMed

    Wang, Chun; Quan, Li-Hui; Guo, Yi; Liu, Chun-Yu; Liao, Yong-Hong

    2007-06-01

    The objective of the present study was to investigate the biodistribution profiles of rizatriptan in the blood and brain of Wistar rats after peroral, subcutaneous, intranasal and intratracheal administration with a particular view to determining the applicability of inhalation delivery to achieve rapid and high availability of the drug in both blood and the brain. Following the intratracheal administration of the drug (4.0mg/kg) to the rats, the absolute bioavailability was found to be 91.2%, significantly higher than those from intranasal or peroral routes, and T(max) in plasma and brain was attained within 2 min, significantly shorter than the T(max) of intranasal ( approximately 10 min in both plasma and brain), subcutaneous (16.7 min in plasma and 22.5 min in brain) and peroral (30.0 min in plasma and 45.0 min in brain) administration. In addition, other pharmacokinetic parameters associated with rapid onset of action including AUC(plasma/brain) and C(max), of intratracheal instillated rizatriptan appeared also to be comparable or superior to those of other delivered routes. Although AUC(brain)/AUC(plasma) ratios after intranasal delivery (43.4%) differed significantly from the ratios shown after intratracheal instillation (23.2%), the AUC(brain 0-120 min) via the latter routes was slightly but not significantly higher than that from the former routes. The results in the present study indicated that pulmonary delivery of rizatriptan may achieve maximum plasma and brain concentrations significantly more rapidly compared with intranasal, subcutaneous and peroral administration and be a promising delivery method with extremely rapid onset of action in the pain relief of migraine. PMID:17267150

  3. Effects of methyl isocyanate on rat brain cells in culture.

    PubMed

    Anderson, D; Goyle, S; Phillips, B J; Tee, A; Beech, L; Butler, W H

    1990-09-01

    Since the disaster in Bhopal, India, people exposed to methyl isocyanate (MIC) have complained of various disorders including neuromuscular dysfunction. In an attempt to get information about such dysfunction we have previously shown that MIC can affect muscle cells in culture. The present communication reports investigations into the effect of MIC on brain cells in culture. MIC was toxic to brain cells and the response was dose related. The observations were supported by light and electron microscopy. PMID:2207030

  4. Kainic acid induces expression of caveolin-1 in activated microglia in rat brain.

    PubMed

    Takeuchi, Shigeko; Matsuda, Wakoto; Tooyama, Ikuo; Yasuhara, Osamu

    2013-01-01

    Caveolin-1, a major constituent of caveolae, has been implicated in endocytosis, signal transduction and cholesterol transport in a wide variety of cells. In the present study, the expression of caveolin-1 was examined by immunohistochemistry in rat brain with or without systemic injection of kainic acid (KA). Caveolin-1 immunoreactivity was observed in capillary walls in brains of control rats. From one to seven days after KA injection, caveolin-1 immunoreactivity appeared in activated microglia in the cerebral cortex, hippocampus and other brain regions. The strongest immunoreactivity of microglia was seen after 3 days after KA administration. The expression of caveolin-1 was confirmed by RT-PCR and Western blot analysis, respectively. The induction of caveolin-1 expression in microglia activated in response to kainic acid administration suggests its possible role in a modulation of inflammation. PMID:23690214

  5. Brain damage in a new hemorrhagic shock model in the rat using long-term recovery

    SciTech Connect

    Yamauchi, Y.; Kato, H.; Kogure, K. )

    1990-03-01

    A new shock model in the rat using hemorrhagic hypotension for production of brain damage is described. Hemorrhagic shock was induced by lowering arterial blood pressure with bleeding. The MABP was maintained at approximately 25 mm Hg, accompanied by isoelectric EEG, and then shed blood was retransfused. At 1 week of recovery, morphological and 45Ca autoradiographic changes were examined. No brain damage was observed in rats after 1 min of isoelectric EEG. Mild neuronal damage in the hippocampal CA1 subfield was seen in some animals after 2 min of isoelectric EEG. Severe and consistent neuronal loss in the hippocampal CA1 subfield was recognized after 3 min of isoelectric EEG. Additional damage was also seen in the dentate hilus and the thalamus in some animals. This model can be used to study the pathophysiology of postshock brain damage and to assess new therapies following shock.

  6. Inhibition of sterol but not fatty acid synthesis by valproate in developing rat brain in vivo.

    PubMed Central

    Bolaños, J P; Medina, J M; Williamson, D H

    1990-01-01

    The effect of administration of valproate on lipogenesis in the developing rat brain in vivo was studied. Valproate inhibited by 21-38% the rate of 3H2O incorporation into brain sterols, without significantly affecting fatty acid synthesis. Similarly, R-[2-14C]mevalonate incorporation into sterols was inhibited by 33-54%; the low rate of fatty acid synthesis under these conditions was not affected by valproate. Plasma ketone bodies decreased after treatment with valproate. Valproate inhibited (about 50%) both sterol and fatty acid synthesis in livers of weanling rats. It is concluded that valproate can specifically inhibit sterol synthesis in the brain during development, in part at a stage after mevalonate formation, and also by decreased exogenous precursor supply. PMID:2264830

  7. A detailed viscoelastic characterization of the P17 and adult rat brain.

    PubMed

    Elkin, Benjamin S; Ilankovan, Ashok I; Morrison, Barclay

    2011-11-01

    Brain is a morphologically and mechanically heterogeneous organ. Although rat brain is commonly used as an experimental neurophysiological model for various in vivo biomechanical studies, little is known about its regional viscoelastic properties. To address this issue, we have generated viscoelastic mechanical property data for specific anatomical regions of the P17 and adult rat brain. These ages are commonly used in rat experimental models. We measured mechanical properties of both white and gray matter regions in coronal slices with a custom-designed microindentation device performing stress-relaxation indentations to 10% effective strain. Shear moduli calculated for short (100?ms), intermediate (1?sec), and long (20?sec) time points, ranged from ?1?kPa for short term moduli to ?0.4?kPa for long term moduli. Both age and anatomic region were significant factors affecting the time-dependent shear modulus. White matter regions and regions of the cerebellum were much more compliant than those of the hippocampus, cortex, and thalamus. Linear viscoelastic models (Prony series, continuous phase lag, and a power law model) were fit to the time-dependent shear modulus data. All models fit the data equally with no significant differences between them (F-test; p>0.05). The F-test was also used to statistically determine that a Prony series with three time-dependent parameters accurately fit the data with no added benefit from additional terms. The age- and region-dependent rat brain viscoelastic properties presented here will help inform future biomechanical models of the rat brain with specific and accurate regional mechanical property data. PMID:21341982

  8. Entry of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine into the rat brain

    SciTech Connect

    Riachi, N.J.; LaManna, J.C.; Harik, S.I.

    1989-06-01

    We studied blood-to-brain entry of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), 1-methyl-4-phenylpyridinium (MPP+) and butanol in anesthetized rats using the indicator-fractionation method with right atrial bolus injection. Minimal amounts of MPP+, which has low octanol/water partition coefficient, crossed the blood-brain barrier. MPTP and butanol, both of which have high octanol/water partition coefficients, were almost completely extracted by all regions of the brain on the first pass. The main difference between the MPTP and butanol tracers is that butanol rapidly left the brain with an exponential rate constant of 1.24 min-1, whereas MPTP was avidly retained by the brain with a washout rate constant of 0.10 min-1 (mean values for the four brain regions that we studied). Early retention of MPTP by the brain was not due to its rapid metabolism by monoamine oxidase because pargyline pretreatment did not affect this rate constant. However, 30 min after (/sup 3/H)MPTP injection, brain retention of the 3H tracer was reduced significantly by pargyline treatment, and the ratio of brain MPTP/MPP+ was increased markedly.

  9. The influence of microwave radiation from cellular phone on fetal rat brain.

    PubMed

    Jing, Ji; Yuhua, Zhang; Xiao-qian, Yang; Rongping, Jiang; Dong-mei, Guo; Xi, Cui

    2012-03-01

    The increasing use of cellular phones in our society has brought focus on the potential detrimental effects to human health by microwave radiation. The aim of our study was to evaluate the intensity of oxidative stress and the level of neurotransmitters in the brains of fetal rats chronically exposed to cellular phones. The experiment was performed on pregnant rats exposed to different intensities of microwave radiation from cellular phones. Thirty-two pregnant rats were randomly divided into four groups: CG, GL, GM, and GH. CG accepted no microwave radiation, GL group radiated 10 min each time, GM group radiated 30 min, and GH group radiated 60 min. The 3 experimental groups were radiated 3 times a day from the first pregnant day for consecutively 20 days, and on the 21st day, the fetal rats were taken and then the contents of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), malondialdehyde (MDA), noradrenaline (NE), dopamine (DA), and 5-hydroxyindole acetic acid (5-HT) in the brain were assayed. Compared with CG, there were significant differences (P<0.05) found in the contents of SOD, GSH-Px, and MDA in GM and GH; the contents of SOD and GSH-Px decreased and the content of MDA increased. The significant content differences of NE and DA were found in fetal rat brains in GL and GH groups, with the GL group increased and the GH group decreased. Through this study, we concluded that receiving a certain period of microwave radiation from cellular phones during pregnancy has certain harm on fetal rat brains. PMID:22268709

  10. Fetal hypothalamic transplants into brain irradiated rats: Graft morphometry and host behavioral responses

    SciTech Connect

    Pearlman, S.H.; Rubin, P.; White, H.C.; Wiegand, S.J.; Gash, D.M. )

    1990-08-01

    This study was designed to test the hypothesis that neural implants can ameliorate or prevent some of the long-term changes associated with CNS irradiation. Using a rat model, the initial study focused on establishing motor, regulatory, and morphological changes associated with brain radiation treatments. Secondly, fetal hypothalamic tissue grafts were placed into the third ventricle of rats which had been previously irradiated. Adult male Long Evans rats received one of three radiation doses (15, 22.5, 30 Gy) or no radiation. Three days after irradiation, 7 animals in each dose group received an embryonic day 17 hypothalamic graft into the third ventricle while the remaining 8-9 animals in each group received injections of vehicle solution (sham). Few changes were observed in the 15 and 22.5 Gy animals, however rats in the 30 Gy treatment group showed stereotypic and ambulatory behavioral hyperactivity 32 weeks after irradiation. Regulatory changes in the high dose group included decreased growth rate and decreased urine osmolalities, but these measures were extremely variable among animals. Morphological results demonstrated that 30 Gy irradiated animals showed extensive necrosis primarily in the fimbria, which extended into the internal capsule, optic nerve, hippocampus, and thalamus. Hemorrhages were found in the hippocampus, thalamus, and fimbria. Defects in the blood-brain barrier also were evident by entry of intravascularly injected horseradish peroxidase into the parenchyma of the brain. Animals in the 30 Gy grafted group showed fewer behavioral changes and less brain damage than their sham grafted counterparts. Specifically, activity measures were comparable to normal levels, and a dilute urine was not found in the 30 Gy implanted rats. Morphological changes support these behavioral results since only two 30 Gy implanted rats showed necrosis.

  11. Mitochondrial decay in the brains of old rats: ameliorating effect of alpha-lipoic acid and acetyl-L-carnitine.

    PubMed

    Long, Jiangang; Gao, Feng; Tong, Liqi; Cotman, Carl W; Ames, Bruce N; Liu, Jiankang

    2009-04-01

    To investigate the mitochondrial decay and oxidative damage resulting from aging, the activities/kinetics of the mitochondrial complexes were examined in the brains of young and old rats as well as in old rats fed R-alpha-lipoic acid plus acetyl-L-carnitine (LA/ALC). The brain mitochondria of old rats, compared with young rats, had significantly decreased endogenous antioxidants and superoxide dismutase activity; more oxidative damage to lipids and proteins; and decreased activities of complex I, IV and V. Complex I showed a decrease in binding affinity (increase in K(m)) for substrates. Feeding LA/ALC to old rats partially restored age-associated mitochondrial dysfunction to the levels of the young rats. These results indicate that oxidative mitochondrial decay plays an important role in brain aging and that a combination of nutrients targeting mitochondria, such as LA/ALC, could ameliorate mitochondrial decay through preventing mitochondrial oxidative damage. PMID:18846423

  12. Mitochondrial Decay in the Brains of Old Rats: Ameliorating Effect of Alpha-Lipoic Acid and Acetyl-L-carnitine

    PubMed Central

    Long, Jiangang; Gao, Feng; Tong, Liqi; Cotman, Carl W.; Ames, Bruce N.

    2009-01-01

    To investigate the mitochondrial decay and oxidative damage resulting from aging, the activities/kinetics of the mitochondrial complexes were examined in the brains of young and old rats as well as in old rats fed R-α-lipoic acid plus acetyl-L-carnitine (LA/ALC). The brain mitochondria of old rats, compared with young rats, had significantly decreased endogenous antioxidants and superoxide dismutase activity; more oxidative damage to lipids and proteins; and decreased activities of complex I, IV and V. Complex I showed a decrease in binding affinity (increase in Km) for substrates. Feeding LA/ALC to old rats partially restored age-associated mitochondrial dysfunction to the levels of the young rats. These results indicate that oxidative mitochondrial decay plays an important role in brain aging and that a combination of nutrients targeting mitochondria, such as LA/ALC, could ameliorate mitochondrial decay through preventing mitochondrial oxidative damage. PMID:18846423

  13. Cloning and expression of a rat brain. alpha. sub 2B -adrenergic receptor

    SciTech Connect

    Flordellis, C.S.; Handy, D.E.; Bresnahan, M.R.; Zannis, V.I.; Gavras, H. )

    1991-02-01

    The authors isolated a cDNA clone (RB{alpha}{sub 2B}) and its homologous gene (GR{alpha}{sub 2B}) encoding an {alpha}{sub 2B}-adrenergic receptor subtype by screening a rat brain cDNA and a rat genomic library. Nucleotide sequence analysis showed that both clones code for a protein of 458 amino acids, which is 87% homologous to the human kidney glycosylated adrenergic receptor ({alpha}{sub 2}-C4) and divergent from the rat kidney nonglycosylated {alpha}{sub 2B} subtype (RNG{alpha}{sub 2}). Transient expression of RB{alpha}{sub 2B} in COS-7 cells resulted in high-affinity saturable binding for ({sup 3}H)rauwolscine and a high receptor number in the membranes of transfected COS-7 cells. Pharmacological analysis demonstrated that the expressed receptor bound adrenergic ligands with the following order of potency: rauwolscine {gt} yohimbine {gt} prazosin {gt} oxymetazoline, with a prazosin-to-oxymetazoline K{sub i} ratio of 0.34. This profile is characteristic of the {alpha}{sub 2B}-adrenergic receptor subtype. Blotting analysis of rat brain mRNA gave one major and two minor mRNA species, and hybridization with strand-specific probes showed that both DNA strands of GR{alpha}{sub 2B} may be transcriptionally active. These findings show that rat brain expresses an {alpha}{sub 2B}-adrenergic receptor subtype that is structurally different from the rat kidney nonglycosylated {alpha}{sub 2B} subtype. Thus the rat expresses at least two divergent {alpha}{sub 2B}-adrenergic receptors.

  14. Adenosine transport systems on dissociated brain cells from mouse, guinea-pig, and rat

    SciTech Connect

    Johnston, M.E.; Geiger, J.D. )

    1990-09-01

    The kinetics and sodium dependence of adenosine transport were determined using an inhibitor-stop method on dissociated cell body preparations obtained from mouse, guinea-pig and rat brain. Transport affinity (KT) values for the high affinity adenosine transport systems KT(H) were significantly different between these three species; mean +/- SEM values were 0.34 +/- 0.1 in mouse, 0.9 +/- 0.2 in rat, and 1.5 +/- 0.5 microM in guinea-pig. The KT values for the low affinity transport system KT(L) were not different between the three species. Brain cells from rat displayed a significantly greater maximal capacity to accumulate (3H)adenosine (Vmax) than did mouse or guinea-pig for the high affinity system, or than did mouse for the low affinity system. When sodium chloride was replaced in the transport medium with choline chloride, the KT(H) values for guinea-pig and rat were both increased by approximately 100%; only in rat did the change reach statistical significance. The sodium-dependence of adenosine transport in mouse brain was clearly absent. The differences between KT(H) values in mouse and those in guinea-pig or rat were accentuated in the absence of sodium. The differences in kinetic values, ionic requirements, and pharmacological characteristics between adenosine transporters in CNS tissues of mouse, guinea-pig and rat may help account for some of the variability noted among species in terms of their physiological responses to adenosine.

  15. Permittivity coupling across brain regions determines seizure recruitment in partial epilepsy.

    PubMed

    Proix, Timothée; Bartolomei, Fabrice; Chauvel, Patrick; Bernard, Christophe; Jirsa, Viktor K

    2014-11-01

    Brain regions generating seizures in patients with refractory partial epilepsy are referred to as the epileptogenic zone (EZ). During a seizure, paroxysmal activity is not restricted to the EZ, but may recruit other brain regions and propagate activity through large brain networks, which comprise brain regions that are not necessarily epileptogenic. The identification of the EZ is crucial for candidates for neurosurgery and requires unambiguous criteria that evaluate the degree of epileptogenicity of brain regions. To obtain such criteria and investigate the mechanisms of seizure recruitment and propagation, we develop a mathematical framework of coupled neural populations, which can interact via signaling through a slow permittivity variable. The permittivity variable captures effects evolving on slow timescales, including extracellular ionic concentrations and energy metabolism, with time delays of up to seconds as observed clinically. Our analyses provide a set of indices quantifying the degree of epileptogenicity and predict conditions, under which seizures propagate to nonepileptogenic brain regions, explaining the responses to intracerebral electric stimulation in epileptogenic and nonepileptogenic areas. In conjunction, our results provide guidance in the presurgical evaluation of epileptogenicity based on electrographic signatures in intracerebral electroencephalograms. PMID:25378166

  16. Microvesicles from brain-extract-treated mesenchymal stem cells improve neurological functions in a rat model of ischemic stroke.

    PubMed

    Lee, Ji Yong; Kim, Eiru; Choi, Seong-Mi; Kim, Dong-Wook; Kim, Kwang Pyo; Lee, Insuk; Kim, Han-Soo

    2016-01-01

    Transplantation of mesenchymal stem cells (MSCs) was reported to improve functional outcomes in a rat model of ischemic stroke, and subsequent studies suggest that MSC-derived microvesicles (MVs) can replace the beneficial effects of MSCs. Here, we evaluated three different MSC-derived MVs, including MVs from untreated MSCs (MSC-MVs), MVs from MSCs treated with normal rat brain extract (NBE-MSC-MVs), and MVs from MSCs treated with stroke-injured rat brain extract (SBE-MSC-MVs), and tested their effects on ischemic brain injury induced by permanent middle cerebral artery occlusion (pMCAO) in rats. NBE-MSC-MVs and SBE-MSC-MVs had significantly greater efficacy than MSC-MVs for ameliorating ischemic brain injury with improved functional recovery. We found similar profiles of key signalling proteins in NBE-MSC-MVs and SBE-MSC-MVs, which account for their similar therapeutic efficacies. Immunohistochemical analyses suggest that brain-extract-treated MSC-MVs reduce inflammation, enhance angiogenesis, and increase endogenous neurogenesis in the rat brain. We performed mass spectrometry proteomic analyses and found that the total proteomes of brain-extract-treated MSC-MVs are highly enriched for known vesicular proteins. Notably, MSC-MV proteins upregulated by brain extracts tend to be modular for tissue repair pathways. We suggest that MSC-MV proteins stimulated by the brain microenvironment are paracrine effectors that enhance MSC therapy for stroke injury. PMID:27609711

  17. Microvesicles from brain-extract—treated mesenchymal stem cells improve neurological functions in a rat model of ischemic stroke

    PubMed Central

    Lee, Ji Yong; Kim, Eiru; Choi, Seong-Mi; Kim, Dong-Wook; Kim, Kwang Pyo; Lee, Insuk; Kim, Han-Soo

    2016-01-01

    Transplantation of mesenchymal stem cells (MSCs) was reported to improve functional outcomes in a rat model of ischemic stroke, and subsequent studies suggest that MSC-derived microvesicles (MVs) can replace the beneficial effects of MSCs. Here, we evaluated three different MSC-derived MVs, including MVs from untreated MSCs (MSC-MVs), MVs from MSCs treated with normal rat brain extract (NBE-MSC-MVs), and MVs from MSCs treated with stroke-injured rat brain extract (SBE-MSC-MVs), and tested their effects on ischemic brain injury induced by permanent middle cerebral artery occlusion (pMCAO) in rats. NBE-MSC-MVs and SBE-MSC-MVs had significantly greater efficacy than MSC-MVs for ameliorating ischemic brain injury with improved functional recovery. We found similar profiles of key signalling proteins in NBE-MSC-MVs and SBE-MSC-MVs, which account for their similar therapeutic efficacies. Immunohistochemical analyses suggest that brain-extract—treated MSC-MVs reduce inflammation, enhance angiogenesis, and increase endogenous neurogenesis in the rat brain. We performed mass spectrometry proteomic analyses and found that the total proteomes of brain-extract—treated MSC-MVs are highly enriched for known vesicular proteins. Notably, MSC-MV proteins upregulated by brain extracts tend to be modular for tissue repair pathways. We suggest that MSC-MV proteins stimulated by the brain microenvironment are paracrine effectors that enhance MSC therapy for stroke injury. PMID:27609711

  18. Development of peptidergic systems in the rat brain.

    PubMed

    Swaab, D F; Ter Borg, J P

    1981-01-01

    The brain contains a large variety and number of peptides some of which were known earlier as hypothalamic hormones (vasopressin, oxytocin, luteinizing hormone-releasing hormone, thyrotropin-releasing hormone, somatostatin) or as pituitary hormones (the family of opiomelanocortins), while others, not primarily known as hypothalamic or pituitary hormones, may also have endocrine effects (substance P, angiotensin II, neurotensin, bombesin, vasoactive intestinal peptide (VIP), gastrin-cholecystokinin, glucagon, carnosine, bradykinin). These peptides, which form a new class of putative neurotransmitters, are present early in brain development and show important sex differences in both their pattern of innervation and their effects. Their peripheral effects may include intrauterine growth of the placenta and fetus, the timing of birth, acceleration of the course of labour and responses to haemorrhage (redistribution of cardiac output and stimulation of blood cell formation). Endogenous peptides are probably involved in brain development, which may explain their general, permanent and sex-dependent effects when given in the period of rapid brain development. Although peptides might in the future be useful for stimulating recovery from retarded brain development, at present one should be aware of the potential dangers of their use in, for example, obstetrics. PMID:6279364

  19. In vivo and in vitro assessment of brain bioenergetics in aging rats

    PubMed Central

    Vančová, Ol’ga; Bačiak, Ladislav; Kašparová, Svatava; Kucharská, Jarmila; Palacios, Hector H; Horecký, Jaromír; Aliev, Gjumrakch

    2010-01-01

    Abstract Brain energy disorders can be present in aged men and animals. To this respect, the mitochondrial and free radical theory of aging postulates that age-associated brain energy disorders are caused by an imbalance between pro- and anti-oxidants that can result in oxidative stress. Our study was designed to investigate brain energy metabolism and the activity of endogenous antioxidants during their lifespan in male Wistar rats. In vivo brain bioenergetics were measured using 31P nuclear magnetic resonance (NMR) spectroscopy and in vitro by polarographic analysis of mitochondrial oxidative phosphorylation. When compared to the young controls, a significant decrease of age-dependent mitochondrial respiration and adenosine-3-phosphate (ATP) production measured in vitro correlated with significant reduction of forward creatine kinase reaction (kfor) and with an increase in phosphocreatine (PCr)/ATP, PCr/Pi and PME/ATP ratio measured in vivo. The levels of enzymatic antioxidants catalase, GPx and GST significantly decreased in the brain tissue as well as in the peripheral blood of aged rats. We suppose that mitochondrial dysfunction and oxidative inactivation of endogenous enzymes may participate in age-related disorders of brain energy metabolism. PMID:19906014

  20. Application of intracerebral microdialysis to study regional distribution kinetics of drugs in rat brain.

    PubMed

    de Lange, E C; Bouw, M R; Mandema, J W; Danhof, M; de Boer, A G; Breimer, D D

    1995-11-01

    1. The purpose of the present study was to determine whether intracerebral microdialysis can be used for the assessment of local differences in drug concentrations within the brain. 2. Two transversal microdialysis probes were implanted in parallel into the frontal cortex of male Wistar rats, and used as a local infusion and detection device respectively. Within one rat, three different concentrations of atenolol or acetaminophen were infused in randomized order. By means of the detection probe, concentration-time profiles of the drug in the brain were measured at interprobe distances between 1 and 2 mm. 3. Drug concentrations were found to be dependent on the drug as well as on the interprobe distance. It was found that the outflow concentration from the detection probe decreased with increasing lateral spacing between the probes and this decay was much steeper for acetaminophen than for atenolol. A model was developed which allows estimation of kbp/Deff (transfer coefficient from brain to blood/effective diffusion coefficient in brain extracellular fluid), which was considerably larger for the more lipohilic drug, acetaminophen. In addition, in vivo recovery values for both drugs were determined. 4. The results show that intracerebral microdialysis is able to detect local differences in drug concentrations following infusion into the brain. Furthermore, the potential use of intracerebral microdialysis to obtain pharmacokinetic parameters of drug distribution in brain by means of monitoring local concentrations of drugs in time is demonstrated. PMID:8581296

  1. Physiologically based pharmacokinetic modeling to investigate regional brain distribution kinetics in rats.

    PubMed

    Westerhout, Joost; Ploeger, Bart; Smeets, Jean; Danhof, Meindert; de Lange, Elizabeth C M

    2012-09-01

    One of the major challenges in the development of central nervous system (CNS)-targeted drugs is predicting CNS exposure in human from preclinical data. In this study, we present a methodology to investigate brain disposition in rats using a physiologically based modeling approach aiming at improving the prediction of human brain exposure. We specifically focused on quantifying regional diffusion and fluid flow processes within the brain. Acetaminophen was used as a test compound as it is not subjected to active transport processes. Microdialysis probes were implanted in striatum, for sampling brain extracellular fluid (ECF) concentrations, and in lateral ventricle (LV) and cisterna magna (CM), for sampling cerebrospinal fluid (CSF) concentrations. Serial blood samples were taken in parallel. These data, in addition to physiological parameters from literature, were used to develop a physiologically based model to describe the regional brain pharmacokinetics of acetaminophen. The concentration-time profiles of brain ECF, CSF(LV), and CSF(CM) indicate a rapid equilibrium with plasma. However, brain ECF concentrations are on average fourfold higher than CSF concentrations, with average brain-to-plasma AUC(0-240) ratios of 121%, 28%, and 35% for brain ECF, CSF(LV), and CSF(CM), respectively. It is concluded that for acetaminophen, a model compound for passive transport into, within, and out of the brain, differences exist between the brain ECF and the CSF pharmacokinetics. The physiologically based pharmacokinetic modeling approach is important, as it allowed the prediction of human brain ECF exposure on the basis of human CSF concentrations. PMID:22588644

  2. ALA-PDT of glioma cell micro-clusters in BD-IX rat brain

    NASA Astrophysics Data System (ADS)

    Madsen, Steen J.; Angell-Petersen, Even; Spetalen, Signe; Carper, Stephen W.; Ziegler, Sarah A.; Hirschberg, Henry

    2006-02-01

    A significant contributory factor to the poor prognosis of patients with glioblastoma multiforme is the inability of conventional treatments to eradicate infiltrating glioma cells. A syngeneic rat brain tumor model is used to investigate the effects of aminolevulinic acid (ALA)-mediated photodynamic therapy (PDT) on small clusters of tumor cells sequestered in normal brain. The intrinsic sensitivity of rat glioma cells to PDT was investigated by exposing ALA-incubated cells to a range of radiant exposures and irradiances using 635 nm light. Biodistribution studies were undertaken on tumor-bearing animals in order to determine the tumor selectivity of the photosensitizer following systemic administration (i.p.) of ALA. Effects of ALA-PDT on normal brain and gross tumor were evaluated using histopathology. Effects of PDT on isolated glioma cells in normal brain were investigated by treating animals 48 h after tumor cell implantation: a time when the micro-clusters of cells are protected by an intact blood-brain-barrier (BBB). Rat glioma cells in monolayer are susceptible to ALA-PDT - lower irradiances are more effective than higher ones. Fluorescence microscopy of frozen tissue sections showed that photosensitizer is produced with better than 200:1 tumor-to-normal tissue selectivity following i.p. ALA administration. ALA-PDT resulted in significant damage to both gross tumor and normal brain, however, the treatment failed to prolong survival of animals with newly implanted glioma cells compared to non-treated controls if the drug was delivered either i.p. or directly into the brain. In contrast, animals inoculated with tumor cells pre-incubated in vitro with ALA showed a significant survival advantage in response to PDT.

  3. Delivery of large molecules via poly(butyl cyanoacrylate) nanoparticles into the injured rat brain

    NASA Astrophysics Data System (ADS)

    Lin, Yong; Pan, Yaohua; Shi, Yinfeng; Huang, Xianjian; Jia, Nengqin; Jiang, Ji-yao

    2012-04-01

    Poly(n-butyl-2-cyanoacrylate) (PBCA) nanoparticles have been successfully applied to deliver small-molecule drugs to the central nervous system (CNS). However, it is unclear whether PBCA nanoparticles can be used as the delivery system for large molecules to potentially treat traumatic brain injury (TBI). In this study, we tested the capacity of PBCA nanoparticles in passing through the blood-brain barrier (BBB) and transporting large molecules into normal and injured brains in the rat. We first synthesized PBCA nanoparticles by dispersion polymerization and then loaded the particles with either horseradish peroxidase (HRP, 44 kDa) or enhanced green fluorescent protein (EGFP, 29 kDa), which were further coated with polysorbate 80. Next, the polysorbate 80-coated HRP or EGFP-loaded PBCA nanoparticles were intravenously injected into the normal and brain-injured rats. We found that, at 45 min after injection, PBCA nanoparticle-delivered HRP or EGFP was hardly detected in the normal brains of the rats, but a small amount of EGFP carried by PBCA nanoparticles was noted in the normal brains 48 h after administration, which was further confirmed by immunolocalization with anti-EGFP antibodies. In contrast, at 4 h after TBI with a circulation time of 45 min, although the penetration of HRP or EGFP alone was hampered by the BBB, the PBCA nanoparticle-delivered HRP or EGFP was widely distributed near injured sites. Together, our findings provide histological evidence that PBCA nanoparticles can be used as an efficient delivery system for large molecules to overcome the barrier in the brain with TBI.

  4. Aluminum overload increases oxidative stress in four functional brain areas of neonatal rats

    PubMed Central

    2012-01-01

    Background Higher aluminum (Al) content in infant formula and its effects on neonatal brain development are a cause for concern. This study aimed to evaluate the distribution and concentration of Al in neonatal rat brain following Al treatment, and oxidative stress in brain tissues induced by Al overload. Methods Postnatal day 3 (PND 3) rat pups (n =46) received intraperitoneal injection of aluminum chloride (AlCl3), at dosages of 0, 7, and 35 mg/kg body wt (control, low Al (LA), and high Al (HA), respectively), over 14 d. Results Aluminum concentrations were significantly higher in the hippocampus (751.0 ± 225.8 ng/g v.s. 294.9 ± 180.8 ng/g; p < 0.05), diencephalon (79.6 ± 20.7 ng/g v.s. 20.4 ± 9.6 ng/g; p < 0.05), and cerebellum (144.8 ± 36.2 ng/g v.s. 83.1 ± 15.2 ng/g; p < 0.05) in the HA group compared to the control. The hippocampus, diencephalon, cerebellum, and brain stem of HA animals displayed significantly higher levels of lipid peroxidative products (TBARS) than the same regions in the controls. However, the average superoxide dismutase (SOD) activities in the cerebral cortex, hippocampus, cerebellum, and brain stem were lower in the HA group compared to the control. The HA animals demonstrated increased catalase activity in the diencephalon, and increased glutathione peroxidase (GPx) activity in the cerebral cortex, hippocampus, cerebellum, and brain stem, compared to controls. Conclusion Aluminum overload increases oxidative stress (H2O2) in the hippocampus, diencephalon, cerebellum, and brain stem in neonatal rats. PMID:22613782

  5. Multidimensional MRI-CT atlas of the naked mole-rat brain (Heterocephalus glaber).

    PubMed

    Seki, Fumiko; Hikishima, Keigo; Nambu, Sanae; Okanoya, Kazuo; Okano, Hirotaka J; Sasaki, Erika; Miura, Kyoko; Okano, Hideyuki

    2013-01-01

    Naked mole-rats have a variety of distinctive features such as the organization of a hierarchical society (known as eusociality), extraordinary longevity, and cancer resistance; thus, it would be worthwhile investigating these animals in detail. One important task is the preparation of a brain atlas database that provide comprehensive information containing multidimensional data with various image contrasts, which can be achievable using a magnetic resonance imaging (MRI). Advanced MRI techniques such as diffusion tensor imaging (DTI), which generates high contrast images of fiber structures, can characterize unique morphological properties in addition to conventional MRI. To obtain high spatial resolution images, MR histology, DTI, and X-ray computed tomography were performed on the fixed adult brain. Skull and brain structures were segmented as well as reconstructed in stereotaxic coordinates. Data were also acquired for the neonatal brain to allow developmental changes to be observed. Moreover, in vivo imaging of naked mole-rats was established as an evaluation tool of live animals. The data obtained comprised three-dimensional (3D) images with high tissue contrast as well as stereotaxic coordinates. Developmental differences in the visual system were highlighted in particular by DTI. Although it was difficult to delineate optic nerves in the mature adult brain, parts of them could be distinguished in the immature neonatal brain. From observation of cortical thickness, possibility of high somatosensory system development replaced to the visual system was indicated. 3D visualization of brain structures in the atlas as well as the establishment of in vivo imaging would promote neuroimaging researches towards detection of novel characteristics of eusocial naked mole-rats. PMID:24391551

  6. Longitudinal measurements of postnatal rat brain mechanical properties in-vivo.

    PubMed

    Pong, Alice C; Jugé, Lauriane; Cheng, Shaokoon; Bilston, Lynne E

    2016-06-14

    Information on pediatric brain tissue mechanical properties and, more pertinently, how they change during postnatal development remains scarce despite its importance to investigate mechanisms of neural injury. The aim of this study is to determine whether brain mechanical properties change in-vivo during early postnatal development in a rat model. Rat brain viscoelastic properties were measured longitudinally in ten healthy Sprague Dawley rats at five different time points from postnatal week one to week six using magnetic resonance elastography at 800Hz. Myelination and cell density were assessed histologically at the same time points to understand how the underlying tissue microstructure may be associated with changes in mechanical properties at different brain regions. Longitudinal changes in each variable were assessed using a generalized linear model with pairwise comparisons of means between weeks. The brain shear modulus in the cortical gray matter at postnatal week one was 6.3±0.4kPa, and increased significantly from week one to week two (pairwise comparison, p<0.01), remained stable from week two to week four and decreased significantly by week six (pairwise comparison, p<0.001). In the deep gray matter, brain tissue stiffness at postnatal week one was 6.1±2.0kPa, and increased significantly from one to week four (pairwise comparison, p<0.05) before decreasing significantly by week six (pairwise comparison, p<0.001). Stiffness changes were not directly correlated to histological observations. These data suggest that brain tissue shear modulus initially increases during a period equivalent to early childhood, and then decreases during a period equivalent to adolescence. PMID:27126986

  7. Valine entry into rat brain after diet-induced changes in plasma amino acids

    SciTech Connect

    Tews, J.K.; Greenwood, J.; Pratt, O.E.; Harper, A.E.

    1987-01-01

    Passage of amino acids across the blood-brain barrier is assumed to be modified by amino acid composition of the blood. To gain a better understanding of the effects of protein intake on brain amino acid uptake, the authors examined associations among diet, plasma amino acid patterns, and the rate of entry of valine into the brain. Rats were fed diets containing 6, 18, or 50% casein before receiving one meal of a diet containing 0, 6, 18, or 50% casein. After 4-7 h, they were anesthetized and infused intravenously with (/sup 14/C)valine for 5 min before plasma and brain samples were taken for determination of radioactivity and content of individual amino acids. As protein content of the meal was increased from 0 to 50% casein, plasma and brain concentrations of valine and most other large neutral amino acid (LNAA) increased severalfold; also the ratio of (/sup 14/C)valine in brain to that in plasma decreased by >50%, and the rate of valine entry into the brain increased 3.5-fold. The increase in valine flux slowed as plasma levels of LNAA, competitors for valine transport, increased. The results were far more dependent on protein content of the final meal than on that of the adaptation diet; thus changes in protein intake, as reflected in altered plasma amino acid patterns, markedly altered valine entry into the brain.

  8. The androgen-binding protein gene is expressed in male and female rat brain.

    PubMed

    Wang, Y M; Bayliss, D A; Millhorn, D E; Petrusz, P; Joseph, D R

    1990-12-01

    Extracellular androgen-binding proteins (ABP) are thought to modulate the regulatory functions of androgens and the trans-acting nuclear androgen receptor. Testicular ABP and plasma sex hormone-binding globulin (SHBG), which is produced in liver, are encoded by the same gene. We have now found that the ABP-SHBG gene is also expressed in male and female rat brain. Immunoreactive ABP was found to be present in neuronal cell bodies throughout the brain as well as in fibers of the hypothalamic median eminence. The highest concentrations of immunoreactive cell bodies were located in the supraoptic and paraventricular nuclei. Likewise, ABP mRNA was present in all brain regions examined. Analysis of cDNA clones representing brain ABP mRNAs revealed amino acid sequence differences in brain and testicular ABPs. The protein encoded by an alternatively processed RNA has sequence characteristics suggesting that the protein could act as a competitior of ABP binding to cell surface receptors. These data and gene-sequencing experiments indicate that a specific ABP gene promoter is used for transcription initiation in brain. ABP may function in brain as an androgen carrier protein; however, in view of the widespread presence of ABP and ABP mRNA in brain, the protein may have a much broader, yet unknown, function. PMID:1701136

  9. Multicolor in vivo brain imaging with a microscope-coupled fiber-bundle microprobe

    NASA Astrophysics Data System (ADS)

    Doronina-Amitonova, Lyubov V.; Fedotov, Il'ya V.; Efimova, Olga; Chernysheva, Maria; Fedotov, Andrei B.; Anokhin, Konstantin V.; Zheltikov, Aleksei M.

    2012-12-01

    A fiber-bundle microprobe coupled to a confocal optical microscope is shown to enable multicolor in vivo fluorescence brain imaging. A bundle of several thousands of 2.4-μm-diameter optical fibers is employed to deliver multiwavelength laser excitation radiation and to transmit multicolor images from hippocampus tissues in living transgenic mice by picking up a multiplex fluorescent response from green fluorescent protein, nucleic acid counterstains, and neuron tracers.

  10. Astragaloside IV Alleviates Early Brain Injury Following Experimental Subarachnoid Hemorrhage in Rats

    PubMed Central

    Shao, Anwen; Guo, Songxue; Tu, Sheng; Ammar, Al-baadani; Tang, Junjia; Hong, Yuan; Wu, Haijian; Zhang, Jianmin

    2014-01-01

    Astragaloside IV, one of the main effective components isolated from Astragalus membranaceus, has multiple neuroprotective properties, while the effects of astragaloside IV on the attenuation of subarachnoid hemorrhage (SAH)-induced early brain injury (EBI) and its possible mechanisms are unknown. In the present study, we aimed to determine whether astragaloside IV could inhibit oxidative stress, reduce neuronal apoptosis, and improve neurological deficits after experimental SAH in rats. Rats (n=68) were randomly divided into the following groups: Sham group, SAH group, SAH+vehicle group, and SAH+astragaloside IV group. Astragaloside IV or an equal volume of vehicle was administered at 1 h and 6 h after SAH, all the rats were subsequently sacrificed at 24 h after SAH. Mortality, neurological scores, and brain edema were assessed, biochemical tests and histological studies were also performed at that point. SAH induced an increase in the malondialdehyde (MDA) level, neuronal apoptosis, cleaved caspase 3, brain edema and decreased activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). Astragaloside IV treatment reversed these changes and improved neurobehavioral outcomes of SAH rats. Our findings suggested that astragaloside IV may alleviate EBI after SAH through antioxidative and anti-apoptotic effects. PMID:25136262

  11. Curcumin Mediated Attenuation of Carbofuran Induced Oxidative Stress in Rat Brain

    PubMed Central

    Jaiswal, Sunil Kumar; Sharma, Ashish; Gupta, Vivek Kumar; Singh, Rakesh Kumar; Sharma, Bechan

    2016-01-01

    The indiscriminate use of carbofuran to improve crop productivity causes adverse effects in nontargets including mammalian systems. The objective of this study was to evaluate carbofuran induced oxidative stress in rat brain stem and its attenuation by curcumin, a herbal product. Out of 6 groups of rats, 2 groups received two different doses of carbofuran, that is, 15 and 30% of LD50, respectively, for 30 days. Out of these, 2 groups receiving same doses of carbofuran were pretreated with curcumin (100 mg/kg body weight). The levels of antioxidants, TBARS, GSH, SOD, catalase, and GST were determined in rat brain stem. The 2 remaining groups served as placebo and curcumin treated, respectively. The data suggested that carbofuran at different doses caused significant alterations in the levels of TBARS and GSH in dose dependent manner. The TBARS and GSH contents were elevated. The activities of SOD, catalase, and GST were significantly inhibited at both doses of carbofuran. The ratio of P/A was also found to be sharply increased. The pretreatment of curcumin exhibited significant protection from carbofuran induced toxicity. The results suggested that carbofuran at sublethal doses was able to induce oxidative stress in rat brain which could be attenuated by curcumin. PMID:27213055

  12. Melanin-concentrating hormone: unique peptide neuronal systems in the rat brain and pituitary gland

    SciTech Connect

    Zamir, N.; Skofitsch, G.; Bannon, M.J.; Jacobowitz, D.M.

    1986-03-01

    A unique neuronal system was detected in the rat central nervous system by immunohistochemistry and radioimmunoassay with antibodies to salmon melanin-concentrating hormone (MCH). MCH-like immunoreactive (MCH-LI) cell bodies were confined to the hypothalamus. MCH-LI fibers were found throughout the brain but were most prevalent in hypothalamus, mesencephalon, and pons-medulla regions. High concentrations of MCH-LI were measured in the hypothalamic medial forebrain bundle (MFB), posterior hypothalamic nucleus, and nucleus of the diagonal band. Reversed-phase high-performance liquid chromatography of MFB extracts from rat brain indicate that MCH-like peptide from the rat has a different retention time than that of the salmon MCH. An osmotic stimuls (2% NaCl as drinking water for 120 hr) caused a marked increase in MCH-LI concentrations in the lateral hypothalamus and neurointermediate lobe. The present studies establish the presence of MCH-like peptide in the rat brain. The MCH-LI neuronal system is well situated to coordinate complex functions such as regulation of water intake.

  13. Quantitative autoradiographic assessment of sup 55 Fe-RBC distribution in rat brain

    SciTech Connect

    Lin, S.Z.; Nakata, H.; Tajima, A.; Gruber, K.; Acuff, V.; Patlak, C.; Fenstermacher, J. )

    1990-11-01

    A simple in vivo technique of labeling erythrocytes (RBCs) with {sup 55}Fe was developed for quantitative autoradiography (QAR). This procedure involved injecting 5-6 ml of ({sup 55}Fe)ferrous citrate solution (1 mCi/ml) intraperitoneally into donor rats. The number of labeled RBCs reached a maximum at around 7 days and declined very slowly thereafter. Labeled RBCs were harvested from donor rats and used for RBC volume measurement in awake rats. Brain radioactivity was assayed by QAR, which yielded spatial resolution of greater than 50 microns. Tight nearly irreversible binding of {sup 55}Fe to RBCs was found in vivo and in vitro. More than 99.5% of the {sup 55}Fe in the blood of donor rats was bound to RBCs. Because of this, labeled blood can be taken from donors and injected into recipients without further preparation. The tissue absorption of {sup 55}Fe emissions was the same in gray and white matter. Microvascular RBC volumes measured with {sup 55}Fe-labeled RBCs agreed with those assayed with {sup 51}Cr-labeled RBCs for many, but not all, brain areas. In conclusion, {sup 55}Fe-RBCs can be readily prepared by this technique and accurately quantitated in brain tissue by QAR.

  14. Curcumin Mediated Attenuation of Carbofuran Induced Oxidative Stress in Rat Brain.

    PubMed

    Jaiswal, Sunil Kumar; Sharma, Ashish; Gupta, Vivek Kumar; Singh, Rakesh Kumar; Sharma, Bechan

    2016-01-01

    The indiscriminate use of carbofuran to improve crop productivity causes adverse effects in nontargets including mammalian systems. The objective of this study was to evaluate carbofuran induced oxidative stress in rat brain stem and its attenuation by curcumin, a herbal product. Out of 6 groups of rats, 2 groups received two different doses of carbofuran, that is, 15 and 30% of LD50, respectively, for 30 days. Out of these, 2 groups receiving same doses of carbofuran were pretreated with curcumin (100 mg/kg body weight). The levels of antioxidants, TBARS, GSH, SOD, catalase, and GST were determined in rat brain stem. The 2 remaining groups served as placebo and curcumin treated, respectively. The data suggested that carbofuran at different doses caused significant alterations in the levels of TBARS and GSH in dose dependent manner. The TBARS and GSH contents were elevated. The activities of SOD, catalase, and GST were significantly inhibited at both doses of carbofuran. The ratio of P/A was also found to be sharply increased. The pretreatment of curcumin exhibited significant protection from carbofuran induced toxicity. The results suggested that carbofuran at sublethal doses was able to induce oxidative stress in rat brain which could be attenuated by curcumin. PMID:27213055

  15. A Multidimensional Magnetic Resonance Histology Atlas of the Wistar Rat Brain

    PubMed Central

    Johnson, G. Allan; Calabrese, Evan; Badea, Alexandra; Paxinos, George; Watson, Charles

    2012-01-01

    We have produced a multidimensional atlas of the adult Wistar rat brain based on magnetic resonance histology (MRH). This MR atlas has been carefully aligned with the widely used Paxinos-Watson atlas based on optical sections to allow comparisons between histochemical and immuno-marker data, and the use of the Paxinos-Watson abbreviation set. Our MR atlas attempts to make a seamless connection with the advantageous features of the Paxinos-Watson atlas, and to extend the utility of the data through the unique capabilities of MR histology: a) ability to view the brain in the skull with limited distortion from shrinkage or sectioning; b) isotropic spatial resolution, which permits sectioning along any arbitrary axis without loss of detail; c) three-dimensional (3D) images preserving spatial relationships; and d) widely varied contrast dependent on the unique properties of water protons. 3D diffusion tensor images (DTI) at what we believe to be the highest resolution ever attained in the rat provide unique insight into white matter structures and connectivity. The 3D isotropic data allow registration of multiple data sets into a common reference space to provide average atlases not possible with conventional histology. The resulting multidimensional atlas that combines Paxinos-Watson with multidimensional MRH images from multiple specimens provides a new, comprehensive view of the neuroanatomy of the rat and offers a collaborative platform for future rat brain studies. PMID:22634863

  16. Rifaximin, but not growth factor 1, reduces brain edema in cirrhotic rats

    PubMed Central

    Òdena, Gemma; Miquel, Mireia; Serafín, Anna; Galan, Amparo; Morillas, Rosa; Planas, Ramon; Bartolí, Ramon

    2012-01-01

    AIM: To compare rifaximin and insulin-like growth factor (IGF)-1 treatment of hyperammonemia and brain edema in cirrhotic rats with portal occlusion. METHODS: Rats with CCl4-induced cirrhosis with ascites plus portal vein occlusion and controls were randomized into six groups: Cirrhosis; Cirrhosis + IGF-1; Cirrhosis + rifaximin; Controls; Controls + IGF-1; and Controls + rifaximin. An oral glutamine-challenge test was performed, and plasma and cerebral ammonia, glucose, bilirubin, transaminases, endotoxemia, brain water content and ileocecal cultures were measured and liver histology was assessed. RESULTS: Rifaximin treatment significantly reduced bacterial overgrowth and endotoxemia compared with cirrhosis groups, and improved some liver function parameters (bilirubin, alanine aminotransferase and aspartate aminotransferase). These effects were associated with a significant reduction in cerebral water content. Blood and cerebral ammonia levels, and area-under-the-curve values for oral glutamine-challenge tests were similar in rifaximin-treated cirrhotic rats and control group animals. By contrast, IGF-1 administration failed to improve most alterations observed in cirrhosis. CONCLUSION: By reducing gut bacterial overgrowth, only rifaximin was capable of normalizing plasma and brain ammonia and thereby abolishing low-grade brain edema, alterations associated with hepatic encephalopathy. PMID:22563196

  17. Wearable 3-D Photoacoustic Tomography for Functional Brain Imaging in Behaving Rats.

    PubMed

    Tang, Jianbo; Coleman, Jason E; Dai, Xianjin; Jiang, Huabei

    2016-01-01

    Understanding the relationship between brain function and behavior remains a major challenge in neuroscience. Photoacoustic tomography (PAT) is an emerging technique that allows for noninvasive in vivo brain imaging at micrometer-millisecond spatiotemporal resolution. In this article, a novel, miniaturized 3D wearable PAT (3D-wPAT) technique is described for brain imaging in behaving rats. 3D-wPAT has three layers of fully functional acoustic transducer arrays. Phantom imaging experiments revealed that the in-plane X-Y spatial resolutions were ~200 μm for each acoustic detection layer. The functional imaging capacity of 3D-wPAT was demonstrated by mapping the cerebral oxygen saturation via multi-wavelength irradiation in behaving hyperoxic rats. In addition, we demonstrated that 3D-wPAT could be used for monitoring sensory stimulus-evoked responses in behaving rats by measuring hemodynamic responses in the primary visual cortex during visual stimulation. Together, these results show the potential of 3D-wPAT for brain study in behaving rodents. PMID:27146026

  18. Transcranial MRI-guided FUS-induced BBB opening in the rat brain

    NASA Astrophysics Data System (ADS)

    Treat, Lisa H.; McDannold, Nathan J.; Hynynen, Kullervo

    2001-05-01

    The blood-brain barrier (BBB) has been a major limitation in treating diseases of the brain because therapeutic agents are either unable to penetrate or have dose-limiting side effects in diffuse opening of the BBB. A previous study demonstrated that focused ultrasound (FUS) can locally open the BBB in a rabbit model when a piece of skull is removed and that magnetic resonance imaging (MRI) can be used to guide and monitor the procedure. This study examined whether the same desired effect of local BBB disruption can be achieved by applying FUS through an intact skull in a rat model. Twenty-eight Sprague-Dawley rats were anesthetized, shaved, and sonicated at four focal locations in the brain, using a 1.5-MHz focused transducer. Contrast-enhanced MR images were obtained before and after sonication. The images indicated contrast agent penetration at the focal coordinates following Optison-enhanced sonication. This study demonstrated that the distortion of the ultrasound beam by the rat skull was not significant enough to inhibit focal BBB opening. Subsequent experiments using MRI-guided FUS to aid in targeted drug delivery to brain tumors in a rodent model could thus be performed more efficiently without cranial surgery. [Research funded by NIH Grant No. CA76550.

  19. Effect of a chronic GSM 900 MHz exposure on glia in the rat brain.

    PubMed

    Ammari, Mohamed; Brillaud, Elsa; Gamez, Christelle; Lecomte, Anthony; Sakly, Mohsen; Abdelmelek, Hafedh; de Seze, René

    2008-01-01

    Extension of the mobile phone technology raises concern about the health effects of 900 MHz microwaves on the central nervous system (CNS). In this study we measured GFAP expression using immunocytochemistry method, to evaluate glial evolution 10 days after a chronic exposure (5 days a week for 24 weeks) to GSM signal for 45 min/day at a brain-averaged specific absorption rate (SAR)=1.5 W/kg and for 15 min/day at a SAR=6 W/kg in the following rat brain areas: prefrontal cortex (PfCx), caudate putamen (Cpu), lateral globus pallidus of striatum (LGP), dentate gyrus of hippocampus (DG) and cerebellum cortex (CCx). In comparison to sham or cage control animals, rats exposed to chronic GSM signal at 6 W/kg have increased GFAP stained surface areas in the brain (p<0.05). But the chronic exposure to GSM at 1.5 W/kg did not increase GFAP expression. Our results indicated that chronic exposure to GSM 900 MHz microwaves (SAR=6 W/kg) may induce persistent astroglia activation in the rat brain (sign of a potential gliosis). PMID:18424058

  20. Protective Effect of Solanum nigrum Leaves Extract on Immobilization Stress Induced Changes in Rat's Brain

    PubMed Central

    Zaidi, Syed Kashif; Hoda, Md. Nasrul; Tabrez, Shams; Ansari, Shakeel Ahmed; Jafri, Mohammad Alam; Shahnawaz Khan, Mohd; Hasan, Shirin; Alqahtani, Mohammed H.; Mohammed Abuzenadah, Adel; Banu, Naheed

    2014-01-01

    The prophylactic or curative antioxidant efficacy of crude extract and the active constituent of S. nigrum leaves were evaluated in modulating inherent antioxidant system altered due to immobilization stress in rat brain tissues, in terms of measurement of glutathione (GSH), lipid peroxidation (thiobarbituric acid reactive substances, TBARS), and free radical scavenging enzymes activities. Rats were treated with single dose of crude extract of S. nigrum prior to and after 6 h of immobilization stress exposure. Exposure to immobilization stress resulted in a decrease in the brain levels of glutathione, SOD, GST, and catalase, with an increase in thiobarbituric acid reactive substances (TBARS) levels. Treatment of S. nigrum extract and its active constituents to both pre- and poststressed rats resulted in significant modulation in the above mentioned parameters towards their control values with a relative dominance by the latter. Brain is vulnerable to stress induced prooxidant insult due to high levels of fat content. Thus, as a safe herbal medication the S. nigrum leaves extract or its isolated constituents can be used as nutritional supplement for scavenging free radicals generated in the brain due to physical or psychological stress or any neuronal diseases per se. PMID:24665335

  1. MALDI Mass Spectrometric Imaging of Lipids in Rat Brain Injury Models

    NASA Astrophysics Data System (ADS)

    Hankin, Joseph A.; Farias, Santiago E.; Barkley, Robert M.; Heidenreich, Kim; Frey, Lauren C.; Hamazaki, Kei; Kim, Hee-Yong; Murphy, Robert C.

    2011-06-01

    Matrix-assisted laser desorption ionization/ionization imaging mass spectrometry (MALDI IMS) with a time-of-flight analyzer was used to characterize the distribution of lipid molecular species in the brain of rats in two injury models. Ischemia/reperfusion injury of the rat brain after bilateral occlusion of the carotid artery altered appearance of the phospholipids present in the hippocampal region, specifically the CA1 region. These brain regions also had a large increase in the ion abundance at m/z 548.5 and collisional activation supported identification of this ion as arising from ceramide (d18:1/18:0), a lipid known to be associated with cellular apoptosis. Traumatic brain injury model in the rat was examined by MALDI IMS and the area of damage also showed an increase in ceramide (d18:1/18:0) and a remarkable loss of signal for the potassium adduct of the most abundant phosphocholine molecular species 16:0/18:1 (PC) with a corresponding increase in the sodium adduct ion. This change in PC alkali attachment ion was suggested to be a result of edema and influx of extracellular fluid likely through a loss of Na/K-ATPase caused by the injury. These studies reveal the value of MALDI IMS to examine tissues for changes in lipid biochemistry and will provide data needed to eventually understand the biochemical mechanisms relevant to tissue injury.

  2. PDE5 Inhibitors Enhance Tumor Permeability and Efficacy of Chemotherapy in a Rat Brain Tumor Model

    PubMed Central

    Black, Keith L.; Yin, Dali; Ong, John M.; Hu, Jinwei; Konda, Bindu M.; Wang, Xiao; Ko, MinHee K.; Bayan, Jennifer-Ann; Sacapano, Manuel R.; Espinoza, Andreas; Morris-Irvin, Dwain K; Shu, Yan

    2008-01-01

    The blood-brain tumor barrier (BTB) significantly limits delivery of therapeutic concentrations of chemotherapy to brain tumors. A novel approach to selectively increase drug delivery is pharmacologic modulation of signaling molecules that regulate BTB permeability, such as those in cGMP signaling. Here we show that oral administration of sildenafil (Viagra) and vardenafil (Levitra), inhibitors of cGMP-specific PDE5, selectively increased tumor capillary permeability in 9L gliosarcoma-bearing rats with no significant increase in normal brain capillaries. Tumor-bearing rats treated with the chemotherapy agent, adriamycin, in combination with vardenafil survived significantly longer than rats treated with adriamycin alone. The selective increase in tumor capillary permeability appears to be mediated by a selective increase in tumor cGMP levels and increased vesicular transport through tumor capillaries, and could be attenuated by iberiotoxin, a selective inhibitor for calcium-dependent potassium (KCa) channels, that are effectors in cGMP signaling. The effect by sildenafil could be further increased by simultaneously using another BTB “opener”, bradykinin. Collectively, this data demonstrates that oral administration of PDE5 inhibitors selectively increases BTB permeability and enhance anti-tumor efficacy for a chemotherapeutic agent. These findings have significant implications for improving delivery of anti-tumor agents to brain tumors. PMID:18674521

  3. Wearable 3-D Photoacoustic Tomography for Functional Brain Imaging in Behaving Rats

    PubMed Central

    Tang, Jianbo; Coleman, Jason E.; Dai, Xianjin; Jiang, Huabei

    2016-01-01

    Understanding the relationship between brain function and behavior remains a major challenge in neuroscience. Photoacoustic tomography (PAT) is an emerging technique that allows for noninvasive in vivo brain imaging at micrometer-millisecond spatiotemporal resolution. In this article, a novel, miniaturized 3D wearable PAT (3D-wPAT) technique is described for brain imaging in behaving rats. 3D-wPAT has three layers of fully functional acoustic transducer arrays. Phantom imaging experiments revealed that the in-plane X-Y spatial resolutions were ~200 μm for each acoustic detection layer. The functional imaging capacity of 3D-wPAT was demonstrated by mapping the cerebral oxygen saturation via multi-wavelength irradiation in behaving hyperoxic rats. In addition, we demonstrated that 3D-wPAT could be used for monitoring sensory stimulus-evoked responses in behaving rats by measuring hemodynamic responses in the primary visual cortex during visual stimulation. Together, these results show the potential of 3D-wPAT for brain study in behaving rodents. PMID:27146026

  4. Characterization of angiotensin-binding sites in the bovine adrenal and the rat brain

    SciTech Connect

    Rogulja, I.

    1989-01-01

    The first study was designed to determine whether systemically administered MSG affects neurons in the CVOs that are potentially important in mediating angiotensin-dependent responses. Rats were pretreated with MSG and the receptors for angiotensin II were assayed by radioligand binding in brain homogenates from the septum anteroventral third ventricular region (AV3V) and the thalamus/hypothalamus region using {sup 125}I-angiotensin II as the radioligand. The results of this experiment indicate that systematically administered MSG in the rat significantly reduced the number (Bmax) of Ang II receptors in a tissue sample which contained both extra blood-brain barrier organs as well as tissue within the blood-brain barrier with no change in the affinity (Kd) of the binding sites. The second chapter reports the successful solubilization of bovine adrenal {sup 125}I Ang II and {sup 125}I Sar{sup 1},Ile{sup 8}-Ang II binding sites with the detergent CHAPS. The results of our studies indicate the presence of two angiotensin binding sites. The one site is specific for naturally occurring angiotensins as well as sarcosine-1 substituted angiotensin analogues. The other site which can be optimally stabilized be re-addition of 0.3% CHAPS into the incubation assay binds sarcosine-1 substituted angiotensins exclusively. Hydrophobic interaction chromatography experiments suggest that these sites, possibly, represent distinct proteins. The third chapter discusses the successful solubilization and partial characterization of the rat brain angiotensin receptor.

  5. Distribution of kappa opioid receptors in the brain of young and old male rats

    SciTech Connect

    Maggi, R.; Limonta, P.; Dondi, D.; Martini, L.; Piva, F. )

    1989-01-01

    The experiments to be described have been designed in order to: (a) provide new information on the concentrations of opioid kappa receptors in different regions of the brain of the male rats; and (b) to analyze whether the density of brain kappa receptors might be modified by the process of aging. The concentration of kappa receptors was investigated in the hypothalamus, amygdala, mesencephalon, corpus striatum, hippocampus, thalamus, frontal poles, anterior and posterior cortex collected from male rats of 2 and 19 months of age. {sup 3}H-bremazocine (BRZ) was used as the ligand of kappa receptors, after protection of mu and delta receptors respectively with dihydromorphine and d-ala-d-leu-enkephalin. The results obtained show that: (1) in young male rats, the number of kappa opioid receptors is different in the various brain areas examined. (2) Aging exerts little influence on the number of kappa receptors in the majority of the brain structures considered. However in the amygdala and in the thalamus the number of kappa receptors was increased in old animals.

  6. Role of 5-hydroxytryptamine in the regulation of brain neuropeptides in normal and diabetic rat

    NASA Technical Reports Server (NTRS)

    Kolta, Malak G.; Williams, Byron B.; Soliman, Karam F. A.

    1986-01-01

    The effect of 5-hydroxytryptamine (5-HT) alteration on brain dopamine (DA), norepinephrine (NE), beta-endorphin (beta-E), and immunoreactive insulin was studied in Sprague-Dawley diabetic and control rats. Diabetes was induced using alloxan (45 mg/kg), 15 days prior to sacrificing. Both control and diabetic animals were treated with either p-chlorophenylalanine (PCPA, 300 mg/kg) three days prior to sacrificing or fluoxetine (10 mg/kg) twice daily for three days. PCPA treatment significantly decreased brain content of 5-HT and 5-hydroxyindolel acetic acid, while it caused significant increase and decrease in brain beta-E and insulin levels, respectively, in both normal and diabetic rat. Meanwhile, the administration of fluoxetine resulted in significant increase in brain content of 5-HT, DA, NE and insulin but significant decline of beta-E in diabetic and saline control rats. The results of this experiment indicate that 5-HT may be regulating both beta-E and insulin regardless of the availability of pancreatic insulin.

  7. Effects of long-term treatment with methyl mercury on the developing rat brain

    SciTech Connect

    Lindstroem, H.; Luthman, J.; Olson, L. ); Oskarsson, A.; Sundberg, J. )

    1991-12-01

    Sprague-Dawley rats were exposed to low doses of methyl mercury (3.9 mg mercury/kg diet), via their dams during gestation and lactation and directly via their diet until sacrifice at 50 days postpartum, in order to study possible detrimental effects on CNS development. The methyl mercury exposure of the rats resulted in a brain concentration of 1.45 {plus minus} 0.06 mg mercury/kg wet weight (mean {plus minus} SEM). No general toxic effects were observed; body weight was not affected, brain weight was only slightly increased. No discernible general morphological alterations were seen in the brain as evaluated using cresyl violet histology. Furthermore, no effects on GFA-positive astrocytes in brain sections were observed and computerized morphometry of smeared astrocytes from frontal cortex, hippocampus, and cerebellum did not reveal any effects of the methyl mercury treatment. The noradrenaline (NA) and dopamine (DA) systems were also studied. In cerebellum the NA levels were increased whereas in other regions analyzed NA and DA levels were unchanged. Thus, long-term low-dosage exposure of methyl mercury in rats during development does not appear to exert any major effects on the morphological maturation of neurons and astrocytes. However, the results indicate the effects may occur in specific transmitter-identified systems, such as the NA input to cerebellum.

  8. Large-Scale Brain Network Coupling Predicts Total Sleep Deprivation Effects on Cognitive Capacity

    PubMed Central

    Wang, Lubin; Zhai, Tianye; Zou, Feng; Ye, Enmao; Jin, Xiao; Li, Wuju; Qi, Jianlin; Yang, Zheng

    2015-01-01

    Interactions between large-scale brain networks have received most attention in the study of cognitive dysfunction of human brain. In this paper, we aimed to test the hypothesis that the coupling strength of large-scale brain networks will reflect the pressure for sleep and will predict cognitive performance, referred to as sleep pressure index (SPI). Fourteen healthy subjects underwent this within-subject functional magnetic resonance imaging (fMRI) study during rested wakefulness (RW) and after 36 h of total sleep deprivation (TSD). Self-reported scores of sleepiness were higher for TSD than for RW. A subsequent working memory (WM) task showed that WM performance was lower after 36 h of TSD. Moreover, SPI was developed based on the coupling strength of salience network (SN) and default mode network (DMN). Significant increase of SPI was observed after 36 h of TSD, suggesting stronger pressure for sleep. In addition, SPI was significantly correlated with both the visual analogue scale score of sleepiness and the WM performance. These results showed that alterations in SN-DMN coupling might be critical in cognitive alterations that underlie the lapse after TSD. Further studies may validate the SPI as a potential clinical biomarker to assess the impact of sleep deprivation. PMID:26218521

  9. Brain Uptake of the Drug of Abuse γ-Hydroxybutyric Acid in Rats

    PubMed Central

    Roiko, Samuel A.; Felmlee, Melanie A.

    2012-01-01

    γ-Hydroxybutyric acid (GHB) is an endogenous compound and a substrate for the ubiquitous monocarboxylate transporter (MCT) family. GHB is also a drug of abuse due to its sedative/hypnotic and euphoric effects, with overdoses resulting in toxicity and death. The goal of this study was to characterize the distribution of GHB into the brain using in vivo microdialysis and in vitro uptake studies and to determine concentration-effect relationships for GHB in a rat animal model. GHB was administered to rats (400, 600, and 800 mg/kg i.v.), and blood, dialysate, and urine were collected for 6 h post-GHB administration. The GHB plasma and extracellular fluid (ECF) concentration-time profiles revealed that GHB concentrations in ECF closely followed plasma GHB concentrations. Sleep time increased in a dose-dependent manner (91 ± 18, 134 ± 11, and 168 ± 13 min, for GHB 400, 600, and 800 mg/kg, respectively). GHB partitioning into brain ECF was not significantly different at 400, 600, and 800 mg/kg. GHB uptake in rat and human brain endothelial cells exhibited concentration dependence. The concentration-dependent uptake of GHB at pH 7.4 was best-fit to a single-transporter model [Km = 18.1 mM (human), 23.3 mM (rat), Vmax = 248 and 258 pmol · mg−1 · min−1 for human and rat, respectively]. These findings indicate that although GHB distribution into the brain is mediated via MCT transporters, it is not capacity-limited over the range of doses studied in this investigation. PMID:22019629

  10. Region-specific changes in presynaptic agmatine and glutamate levels in the aged rat brain.

    PubMed

    Jing, Y; Liu, P; Leitch, B

    2016-01-15

    During the normal aging process, the brain undergoes a range of biochemical and structural alterations, which may contribute to deterioration of sensory and cognitive functions. Age-related deficits are associated with altered efficacy of synaptic neurotransmission. Emerging evidence indicates that levels of agmatine, a putative neurotransmitter in the mammalian brain, are altered in a region-specific manner during the aging process. The gross tissue content of agmatine in the prefrontal cortex (PFC) of aged rat brains is decreased whereas levels in the temporal cortex (TE) are increased. However, it is not known whether these changes in gross tissue levels are also mirrored by changes in agmatine levels at synapses and thus could potentially contribute to altered synaptic function with age. In the present study, agmatine levels in presynaptic terminals in the PFC and TE regions (300 terminals/region) of young (3month; n=3) and aged (24month; n=3) brains of male Sprague-Dawley rats were compared using quantitative post-embedding immunogold electron-microscopy. Presynaptic levels of agmatine were significantly increased in the TE region (60%; p<0.001) of aged rats compared to young rats, however no significant differences were detected in synaptic levels in the PFC region. Double immunogold labeling indicated that agmatine and glutamate were co-localized in the same synaptic terminals, and quantitative analyses revealed significantly reduced glutamate levels in agmatine-immunopositive synaptic terminals in both regions in aged rats compared to young animals. This study, for the first time, demonstrates differential effects of aging on agmatine and glutamate in the presynaptic terminals of PFC and TE. Future research is required to understand the functional significance of these changes and the underlying mechanisms. PMID:26548412

  11. [Effect of antenatal hypoxia on homocarnosine levels in the brain and blood of rats of various ages].

    PubMed

    Bondarenko, T I; Kondrashova, I N

    1988-01-01

    Content of homocarnosine was studied in brain and blood of 14, 30 and 70 days old rats, mothers of which were subjected to hypoxia, corresponding to the height 9,000 m within 1 hr, during 2 week pregnancy. In 14 days old animals content of homocarnosine was increased by 43% in brain and 2-fold in blood, in 30 days old animals it was decreased by 13% in brain and increased 5-fold in blood after the antenatal hypoxia as compared with controls. Content of homocarnosine was similar to control values in brain and blood of 70 days old rats with antenatal hypoxia. PMID:3195129

  12. Magnetic-field-induced DNA strand breaks in brain cells of the rat.

    PubMed Central

    Lai, Henry; Singh, Narendra P

    2004-01-01

    In previous research, we found that rats acutely (2 hr) exposed to a 60-Hz sinusoidal magnetic field at intensities of 0.1-0.5 millitesla (mT) showed increases in DNA single- and double-strand breaks in their brain cells. Further research showed that these effects could be blocked by pretreating the rats with the free radical scavengers melatonin and N-tert-butyl-alpha-phenylnitrone, suggesting the involvement of free radicals. In the present study, effects of magnetic field exposure on brain cell DNA in the rat were further investigated. Exposure to a 60-Hz magnetic field at 0.01 mT for 24 hr caused a significant increase in DNA single- and double-strand breaks. Prolonging the exposure to 48 hr caused a larger increase. This indicates that the effect is cumulative. In addition, treatment with Trolox (a vitamin E analog) or 7-nitroindazole (a nitric oxide synthase inhibitor) blocked magnetic-field-induced DNA strand breaks. These data further support a role of free radicals on the effects of magnetic fields. Treatment with the iron chelator deferiprone also blocked the effects of magnetic fields on brain cell DNA, suggesting the involvement of iron. Acute magnetic field exposure increased apoptosis and necrosis of brain cells in the rat. We hypothesize that exposure to a 60-Hz magnetic field initiates an iron-mediated process (e.g., the Fenton reaction) that increases free radical formation in brain cells, leading to DNA strand breaks and cell death. This hypothesis could have an important implication for the possible health effects associated with exposure to extremely low-frequency magnetic fields in the public and occupational environments. PMID:15121512

  13. Sub-chronic iron overload triggers oxidative stress development in rat brain: implications for cell protection.

    PubMed

    Piloni, Natacha E; Perazzo, Juan C; Fernandez, Virginia; Videla, Luis A; Puntarulo, Susana

    2016-02-01

    This work was aimed to test the hypothesis that sub-chronic administration of iron-dextran (Fe-dextran) (six doses of 50 mg Fe-dextran/kg) to rats triggers a transient oxidative stress in brain and mechanisms of cellular antioxidant defence. After 2 h of administration of the 6th dose, a significant increase of total Fe, the labile Fe pool (LIP), the lipid radical (LR(•))/α-tocopherol (α-T) content ratio were observed, as compared to values in control brain homogenates. The ascorbyl radical (A(•))/ascorbate (AH(-)) content ratio and the oxidation rate of 2',7'-dichlorodihidrofluorescein (DCFH-DA) were significantly higher in Fe-dextran treated rats, as compared to values in brain from control rats after 4 h treatment. An increase in both catalase (CAT) and superoxide dismutase (SOD) activity was observed at 8 and 1-2 h, respectively. No significant changes were detected in the nuclear factor-κB (NF-κB) levels in nuclear extracts from rat brains after 1-8 h of Fe-dextran administration. After 2 h of Fe administration Fe concentration in cortex, striatum and hippocampus was significantly increased as compared to the same areas from control animals. Both, CAT and SOD activities were significantly increased in cortex after Fe administration over control values, without changes in striatum and hippocampus. Taken as a whole, sub-chronic Fe administration enhances the steady state concentration of Fe in the brain LIP that favors the settlement of an initial oxidative stress condition, both at hydrophilic and lipophilic compartments, resulting in cellular protection evidenced by antioxidant enzyme upregulation. PMID:26677163

  14. Oxygen toxicity is reduced by acetylcholinesterase inhibition in the developing rat brain.

    PubMed

    Sifringer, Marco; Bendix, Ivo; von Haefen, Clarissa; Endesfelder, Stefanie; Kalb, Alexander; Bührer, Christoph; Felderhoff-Mueser, Ursula; Spies, Claudia D

    2013-01-01

    The cholinergic anti-inflammatory pathway is a neural mechanism that suppresses the innate inflammatory response and controls inflammation employing acetylcholine as the key endogenous mediator. In this study, we investigated the effects of the cholinergic agonists, physostigmine and donepezil, on neurodegeneration, inflammation and oxidative stress during oxygen toxicity in the developing rat brain. The aim of this study was to investigate the level of neurodegeneration, expression of proinflammatory cytokines, glutathione and lipid peroxidation after hyperoxia and treatment with the acetylcholinesterase (AChE) inhibitors, physostigmine and donepezil in the brain of neonatal rats. Six-day-old Wistar rats were exposed to 80% oxygen for 12-24 h and received 100 μg/kg physostigmine or 200 μg/kg donepezil intraperitoneally. Sex-matched littermates kept in room air and injected with normal saline, physostigmine or donepezil served as controls. Treatment with both inhibitors significantly reduced hyperoxia-triggered activity of AChE, neural cell death and the upregulation of the proinflammatory cytokines IL-1β and TNF-α in the immature rat brain on the mRNA and protein level. In parallel, hyperoxia-induced oxidative stress was reduced by concomitant physostigmine and donepezil administration, as shown by an increased reduced/oxidized glutathione ratio and attenuated malondialdehyde levels, as a sign of lipid peroxidation. Our results suggest that a single treatment with AChE inhibitors at the beginning of hyperoxia attenuated the detrimental effects of oxygen toxicity in the developing brain and may pave the way for AChE inhibitors, which are currently used for the treatment of Alzheimer's disease, as potential candidates for adjunctive neuroprotective therapies to the immature brain. PMID:23445753

  15. Preconditioning with a novel metallopharmaceutical NO donor in anesthetized rats subjected to brain ischemia/reperfusion.

    PubMed

    Campelo, Marcio Wilker Soares; Oriá, Reinaldo Barreto; Lopes, Luiz Gonzaga de França; Brito, Gerly Anne de Castro; Santos, Armenio Aguiar dos; Vasconcelos, Raquel Cavalcante de; Silva, Francisco Ordelei Nascimento da; Nobrega, Beatrice Nuto; Bento-Silva, Moisés Tolentino; Vasconcelos, Paulo Roberto Leitão de

    2012-04-01

    Rut-bpy is a novel nitrosyl-ruthenium complex releasing NO into the vascular system. We evaluated the effect of Rut-bpy (100 mg/kg) on a rat model of brain stroke. Forty rats were assigned to four groups (Saline solution [SS], Rut-bpy, SS+ischemia-reperfusion [SS+I/R] and Rut-bpy+ischemia-reperfusion [Rut-bpy+I/R]) with their mean arterial pressure (MAP) continuously monitored. The groups were submitted (SS+I/R and Rut-bpy+I/R) or not (SS and Rut-bpy) to incomplete global brain ischemia by occlusion of the common bilateral carotid arteries during 30 min followed by reperfusion for further 60 min. Thirty minutes before ischemia, rats were treated pairwise by intraperitoneal injection of saline solution or Rut-bpy. At the end of experiments, brain was removed for triphenyltetrazolium chloride staining in order to quantify the total ischemic area. In a subset of rats, hippocampus was obtained for histopathology scoring, nitrate and nitrite measurements, immunostaining and western blotting of the nuclear factor- κB (NF-κB). Rut-bpy pre-treatment decreased MAP variations during the transition from brain ischemia to reperfusion and decreased the fractional injury area. Rut-bpy pre-treatment reduced NF-κB hippocampal immunostaining and protein expression with improved histopathology scoring as compared to the untreated operated control. In conclusion, Rut-bpy improved the total brain infarction area and hippocampal neuronal viability in part by inhibiting NF-κB signaling and helped to stabilize the blood pressure during the transition from ischemia to reperfusion. PMID:22160748

  16. The effect of diet on the fatty acid compositions of serum, brain, brain mitochondria and myelin in the rat

    PubMed Central

    Rathbone, L.

    1965-01-01

    1. Three groups of female rats (8–12 weeks old) were maintained respectively on a linoleic acid-rich diet, a linoleic acid-poor predominantly saturated-fatty acid diet and a normal diet. Changes in the fatty acid compositions of serum, brain, brain mitochondria-rich fraction and myelin were observed. 2. Of the serum fatty acids, linoleic acid showed the greatest change in the percentage of the total acids in response to diet; the change in the proportion of oleic acid was considerable. The percentages of arachidonic acid in serum fatty acids in the groups on the linoleic acid-rich and linoleic acid-poor diets were similar, but higher than those in the normal group. 3. Changes in the proportions of linoleic acid, arachidonic acid and docosahexaenoic acid occurred in brain fatty acids that to some extent paralleled those occurring in the serum. Changes in the proportions of most other acids in the serum fatty acids were not accompanied by corresponding changes in the brain fatty acids. 4. The percentage fatty acid compositions of a mitochondria-rich fraction and myelin are given, and changes in the relative proportions of linoleic acid, arachidonic acid and possibly some docosapolyenoic acids were demonstrated to occur as a result of diet. 5. The results are discussed in relation to the possible aetiology of multiple sclerosis. PMID:5881652

  17. Liver irradiation causes distal bystander effects in the rat brain and affects animal behaviour

    PubMed Central

    Kovalchuk, Anna; Mychasiuk, Richelle; Muhammad, Arif; Hossain, Shakhawat; Ilnytskyy, Slava; Ghose, Abhijit; Kirkby, Charles; Ghasroddashti, Esmaeel; Kovalchuk, Olga; Kolb, Bryan

    2016-01-01

    Radiation therapy can not only produce effects on targeted organs, but can also influence shielded bystander organs, such as the brain in targeted liver irradiation. The brain is sensitive to radiation exposure, and irradiation causes significant neuro-cognitive deficits, including deficits in attention, concentration, memory, and executive and visuospatial functions. The mechanisms of their occurrence are not understood, although they may be related to the bystander effects. We analyzed the induction, mechanisms, and behavioural repercussions of bystander effects in the brain upon liver irradiation in a well-established rat model. Here, we show for the first time that bystander effects occur in the prefrontal cortex and hippocampus regions upon liver irradiation, where they manifest as altered gene expression and somewhat increased levels of γH2AX. We also report that bystander effects in the brain are associated with neuroanatomical and behavioural changes, and are more pronounced in females than in males. PMID:26678032

  18. Beneficial effects of hyperbaric oxygen on edema in rat hippocampus following traumatic brain injury.

    PubMed

    Liu, Su; Liu, Ying; Deng, Shukun; Guo, Aisong; Wang, Xiubing; Shen, Guangyu

    2015-12-01

    Hyperbaric oxygen (HBO) therapy helps alleviate secondary injury following brain trauma [traumatic brain injury (TBI)], although the mechanisms remain unclear. In this study, we assessed recovery of post-TBI spatial learning and memory in rats using the Morris water maze (MWM) and measured changes in apparent diffusion coefficient in the hippocampus by diffusion-weighted imaging (DWI) to evaluate possible therapeutic effects of HBO on TBI-associated brain edema. DWIs were obtained 8, 24, 48 h, 7 days, and 14 days post-TBI. Daily HBO therapy significantly improved post-TBI MWM performance and reduced edema in the ipsilateral hippocampus, suggesting that the therapeutic efficacy of HBO is mediated, at least in part, by a reduction in brain edema. PMID:26267487

  19. Cypermethrin alters Glial Fibrillary Acidic Protein levels in the rat brain.

    PubMed

    Malkiewicz, Katarzyna; Koteras, Marcin; Folkesson, Ronnie; Brzezinski, Jacek; Winblad, Bengt; Szutowski, Miroslaw; Benedikz, Eirikur

    2006-01-01

    Pyrethroids, widely used insecticides, are biologically active in neurons. Whether they act on the non-neuronal brain cells remains an open question. Thus, the aim of this study was to examine whether Cypermethrin intoxication affects astroglial cells in the rat brain. The levels of Glial Fibrillary Acidic Protein (GFAP) in different brain regions were measured by ELISA following oral treatment with 5 or 10% of LD(50) of Cypermethrin per day for 6 days. A significant decrease of GFAP was observed in different brain regions of treated animals. The cerebral cortex showed the most pronounced effect with GFAP levels reduced to 81% of the controls 2 days after treatment and 77% 21 days after treatment. Although we did not find profound changes in the morphology of astrocytes in Cypermethrin treated animals, the decrease in GFAP suggests that astrocytes were affected by low doses of pyrethroids. The possible consequences were discussed. PMID:21783638

  20. C-peptide-like material in rat brain: response to fasting and glucose ingestion.

    PubMed

    Jezová, D; Vigas, M; Sadlon, J

    1985-12-01

    Because of controversial data on the presence of insulin in the central nervous system, the presence of C-peptide immunoreactivity was followed in acid/ethanol extracts of the rat brain. C-peptide-like material was detected in whole brain extracts as well as in several brain fragments. Immunoreactive C-peptide concentrations were significantly higher in hypothalamus and olfactory bulb as compared to those in other brain regions sampled. Fasting for 72 h resulted in a decrease and oral glucose administration (0.75-1.5 g given in form of 25% water solution 30 min before sacrifice) was followed by an increase of C-peptide-like immunoreactivity in both plasma and hypothalamus. PMID:3878779

  1. In vivo and in vitro effects of fructose on rat brain acetylcholinesterase activity: an ontogenetic study.

    PubMed

    Guimarães, Carine A; Biella, Mairis S; Lopes, Abigail; Deroza, Pedro F; Oliveira, Mariana B; Macan, Tamires P; Streck, Emilio L; Ferreira, Gustavo C; Zugno, Alexandra I; Schuck, Patrícia F

    2014-12-01

    Increased fructose concentrations are the biochemical hallmark of fructosemia, a group of inherited disorders on the metabolic pathway of this sugar. The main clinical findings observed in patients affected by fructosemia include neurological abnormalities with developmental delay, whose pathophysiology is still undefined. In the present work we investigated the in vitro and in vivo effects of fructose on acetylcholinesterase (AchE) activity in brain structures of developing rats. For the in vitro experiments, fructose was added at increasing concentrations to the incubation medium. It was observed that fructose provoked an inhibition of acetylcholinesterase activity in cerebral cortex of 30-day-old-rats, even at low concentrations (0.1 mM). For the in vivo experiments, rats were killed 1 h after a single fructose administration (5 µmol/g). Control group received the same volume of saline solution. We found that AchE activity was increased in cerebral cortex of 30- and 60-day-old rats receiving fructose administration. Finally, we observed that AchE activity was unaffected by acute fructose administration in cerebral cortex, striatum or hippocampus of 15- and 90-day-old rats. The present data suggest that a disruption in cholinergic homeostasis may be involved in the pathophysiology of brain damage observed in young patients affected by fructosemia. PMID:25590728

  2. Protective effects of tetrandrine on brain cells in phenobarbital-dependent and -withdrawn rats.

    PubMed

    Han, Bin; Fu, Ping; Ye, Yun; Zhang, Hong; Wang, Guojun

    2015-03-01

    The aim of this study was to investigate the effects of tetrandrine (Tet) on the brain cells of phenobarbital‑dependant and ‑withdrawn rats, and to explore the underlying mechanisms. A total of 100 rats were randomly divided into five groups: The control group, the phenobarbital‑dependent model group, and Tet‑treated groups of low‑, mid‑ and high‑dosages. Following drug withdrawl, the morphological changes of the frontal lobe cells were examined by hematoxylin and eosin (H&E) staining. Immunohistochemical staining was applied to detect the expression of apoptosis‑related proteins Bcl‑2 and Bax. Reverse transcription‑polymerase chain reaction (RT‑PCR) and western blotting methods were applied to detect the mRNA and protein expression levels of Bcl‑2 and Bax, respectively, in the frontal lobe. The results indicated that Tet effectively reduced the withdrawal symptoms, particularly the weight loss, in phenobarbital‑dependent and ‑withdrawn rats. H&E staining revealed that Tet significantly restored the histopathological changes in the addicted rats in a dose‑dependent manner. The immunohistochemical, RT‑PCR, and western blot analyses indicated that Tet treatment significantly increased the Bcl‑2+ brain cells and the mRNA and protein expression levels of Bcl‑2, and decreased the Bax+ cells and the mRNA and protein expression levels of Bax, as well as elevated the ratio of Bcl‑2/Bax, in phenobarbital‑dependent and ‑withdrawn rats. Tet may inhibit apoptosis in these addicted rats, in a dose‑dependent manner. Tet alleviates the phenobarbital withdrawal symptoms and protects the brain cells against apoptosis, which may be a result of the regulation of the mRNA and protein expression levels of Bcl‑2 and Bax. PMID:25434925

  3. Impaired baroreflex gain during pregnancy in conscious rats: role of brain insulin.

    PubMed

    Azar, Afaf S; Brooks, Virginia L

    2011-02-01

    Pregnancy impairs baroreflex gain, but the mechanism is incompletely understood. To test the hypothesis that reductions in brain insulin contribute, we determined whether pregnant rats exhibit lower cerebrospinal fluid (CSF) insulin concentrations and whether intracerebroventricular infusion of insulin normalizes gain of baroreflex control of heart rate in conscious pregnant rats. CSF insulin was lower in pregnant (68 ± 21 pg/mL) compared to virgin (169 ± 25 pg/mL) rats (P < 0.05). Pregnancy reduced baroreflex gain (pregnant 2.4 ± 0.2 bpm/mm Hg, virgin 4.6 ± 0.3 bpm/mm Hg; P < 0.0001) and the maximum heart rate elicited by hypotension (pregnant 455 ± 15 bpm, virgin 507 ± 12 bpm; P = 0.01). Infusion of insulin (100 μU/min) intracerebroventricularly increased baroreflex gain in pregnant (2.4 ± 0.4 to 3.9 ± 0.5 bpm/mm Hg; P < 0.01) but not virgin (4.6 ± 0.4 to 4.2 ± 0.4 bpm/mm Hg; NS) rats. Maximum heart rate was not altered by intracerebroventricular insulin in either group. Interestingly, while in pregnant rats the baroreflex was unchanged by intracerebroventricular infusion of the artificial CSF vehicle, in virgin rats, vehicle infusion lowered baroreflex gain (4.7 ± 0.3 to 3.9 ± 0.3 bpm/mm Hg; P < 0.05) and the maximum baroreflex heart rate (495 ± 19 to 444 ± 21 bpm; P < 0.05). These data support the hypothesis that brain insulin is required to support optimal baroreflex function and that a decrease in brain insulin contributes to the fall in baroreflex gain during pregnancy. PMID:21149828

  4. Oxidative stress induces the decline of brain EPO expression in aging rats.

    PubMed

    Li, Xu; Chen, Yubao; Shao, Siying; Tang, Qing; Chen, Weihai; Chen, Yi; Xu, Xiaoyu

    2016-10-01

    Brain Erythropoietin (EPO), an important neurotrophic factor and neuroprotective factor, was found to be associated with aging. Studies found EPO expression was significantly decreased in the hippocampus of aging rat compared with that of the youth. But mechanisms of the decline of the brain EPO during aging remain unclear. The present study utilized a d-galactose (d-gal)-induced aging model in which the inducement of aging was mainly oxidative injury, to explore underlying mechanisms for the decline of brain EPO in aging rats. d-gal-induced aging rats (2months) were simulated by subcutaneously injecting with d-gal at doses of 50mg·kg(-1), 150mg·kg(-1) and 250mg·kg(-1) daily for 8weeks while the control group received vehicle only. These groups were all compared with the aging rats (24months) which had received no other treatment. The cognitive impairment was assessed using Morris water maze (MWM) in the prepared models, and the amount of β-galactosidase, the lipid peroxidation product malondialdehyde (MDA) level and the superoxide dismutase (SOD) activity in the hippocampus was examined by assay kits. The levels of EPO, EPOR, p-JAK2 and hypoxia-inducible factor-2α (HIF-2α) in the hippocampus were detected by western blot. Additionally, the correlation coefficient between EPO/EPOR expression and MDA level was analyzed. The MWM test showed that compared to control group, the escape latency was significantly extended and the times of crossing the platform was decreased at the doses of 150mg·kg(-1) and 250mg·kg(-1) (p<0.05). Also, the amount of β-galactosidase and the MDA level in the hippocampus were significantly increased but the SOD activity was significantly decreased (p<0.05, 0.01 and 0.01, respectively). Similar to aging rats, the expressions of EPO, EPOR, p-JAK2, and HIF-2αin the brain of d-gal-treated rats were significantly decreased (p<0.05) at 150mg·kg(-1) and 250mg·kg(-1). Interestingly, negative correlations were found between EPOR (r=-0

  5. Conditioned feeding suppression in rats produced by cross-coupled and simple motions

    NASA Technical Reports Server (NTRS)

    Fox, R. A.; Daunton, N. G.

    1982-01-01

    Results are presented of an experiment on the induction of motion sickness in rats by the use of cross-coupled accelerations of magnitudes similar to those used in human experiments. Accelerations were produced in a seesaw apparatus with rotating disks supporting the animal cages mounted on each seesaw arm, and motion sickness was assessed according to the consumption of a sweet food previously offered to the animals immediately before the motion treatment. During a 1-hour test session 72 h after motion treatment and after a 24-h fast, rats having undergone cross-coupled vertical sinusoidal and rotational motion are observed to consume less food than those having experienced either type of motion alone, or no motion. The ordering of the conditioned suppressive feeding effects is consistent with the amounts of vestibular stimulation produced by the respective motions. The results support the existence of motion sickness effects in rats, even though they are unable to vomit.

  6. Paradoxical augmented relapse in alcohol-dependent rats during deep-brain stimulation in the nucleus accumbens

    PubMed Central

    Hadar, R; Vengeliene, V; Barroeta Hlusicke, E; Canals, S; Noori, H R; Wieske, F; Rummel, J; Harnack, D; Heinz, A; Spanagel, R; Winter, C

    2016-01-01

    Case reports indicate that deep-brain stimulation in the nucleus accumbens may be beneficial to alcohol-dependent patients. The lack of clinical trials and our limited knowledge of deep-brain stimulation call for translational experiments to validate these reports. To mimic the human situation, we used a chronic-continuous brain-stimulation paradigm targeting the nucleus accumbens and other brain sites in alcohol-dependent rats. To determine the network effects of deep-brain stimulation in alcohol-dependent rats, we combined electrical stimulation of the nucleus accumbens with functional magnetic resonance imaging (fMRI), and studied neurotransmitter levels in nucleus accumbens-stimulated versus sham-stimulated rats. Surprisingly, we report here that electrical stimulation of the nucleus accumbens led to augmented relapse behavior in alcohol-dependent rats. Our associated fMRI data revealed some activated areas, including the medial prefrontal cortex and caudate putamen. However, when we applied stimulation to these areas, relapse behavior was not affected, confirming that the nucleus accumbens is critical for generating this paradoxical effect. Neurochemical analysis of the major activated brain sites of the network revealed that the effect of stimulation may depend on accumbal dopamine levels. This was supported by the finding that brain-stimulation-treated rats exhibited augmented alcohol-induced dopamine release compared with sham-stimulated animals. Our data suggest that deep-brain stimulation in the nucleus accumbens enhances alcohol-liking probably via augmented dopamine release and can thereby promote relapse. PMID:27327255

  7. Paradoxical augmented relapse in alcohol-dependent rats during deep-brain stimulation in the nucleus accumbens.

    PubMed

    Hadar, R; Vengeliene, V; Barroeta Hlusicke, E; Canals, S; Noori, H R; Wieske, F; Rummel, J; Harnack, D; Heinz, A; Spanagel, R; Winter, C

    2016-01-01

    Case reports indicate that deep-brain stimulation in the nucleus accumbens may be beneficial to alcohol-dependent patients. The lack of clinical trials and our limited knowledge of deep-brain stimulation call for translational experiments to validate these reports. To mimic the human situation, we used a chronic-continuous brain-stimulation paradigm targeting the nucleus accumbens and other brain sites in alcohol-dependent rats. To determine the network effects of deep-brain stimulation in alcohol-dependent rats, we combined electrical stimulation of the nucleus accumbens with functional magnetic resonance imaging (fMRI), and studied neurotransmitter levels in nucleus accumbens-stimulated versus sham-stimulated rats. Surprisingly, we report here that electrical stimulation of the nucleus accumbens led to augmented relapse behavior in alcohol-dependent rats. Our associated fMRI data revealed some activated areas, including the medial prefrontal cortex and caudate putamen. However, when we applied stimulation to these areas, relapse behavior was not affected, confirming that the nucleus accumbens is critical for generating this paradoxical effect. Neurochemical analysis of the major activated brain sites of the network revealed that the effect of stimulation may depend on accumbal dopamine levels. This was supported by the finding that brain-stimulation-treated rats exhibited augmented alcohol-induced dopamine release compared with sham-stimulated animals. Our data suggest that deep-brain stimulation in the nucleus accumbens enhances alcohol-liking probably via augmented dopamine release and can thereby promote relapse. PMID:27327255

  8. Kinetics of creatine in blood and brain after intraperitoneal injection in the rat.

    PubMed

    Perasso, Luisa; Cupello, Aroldo; Lunardi, Gian Luigi; Principato, Cristina; Gandolfo, Carlo; Balestrino, Maurizio

    2003-06-01

    Creatine has in recent years raised the interest of the neurologist, because it has been used in children with hereditary disorders of creatine metabolism and because experimental data suggest that it may exert a protective effect against various neurological diseases including stroke. Moreover, it is widely used as a nutritional supplement. It is well known that creatine crosses the blood-brain barrier with difficulty, however its accumulation into the brain after systemic administration is still not completely known. In the present experiments we studied its accumulation into rat brain tissue after intraperitoneal (i.p.) single or repeated injections. After a single injection of 160 mg/kg, radioactively labelled creatine (14C-creatine) entered the brain to a limited extent. It reached a plateau value of around 70 microM above baseline, that remained stable for at least 9 h. This amount of exogenous creatine obviously added to the endogenous creatine store. This increase is a minor one, since endogenous creatine has a brain concentration of about 10 mM. In accordance with this conclusion, when single or repeated injections of unlabelled ('cold') creatine were administered to rats, no sizable increase could be measured with high-performance liquid chromatography in the brain levels of either this compound or its phosphorylated derivative, phosphocreatine. Although our data clearly show some passage of serum creatine into the brain, other strategies are needed to improve passage of creatine across the blood-brain barrier in a way that it may be suitable to treat acute conditions like stroke. PMID:12742622

  9. Changes in Met- and Leu-enkephalin concentrations in brain structures of rats with burn shock

    SciTech Connect

    Zaets, T.L.; Borodulin, A.G.; Maizelis, M.Ya.; Shikhov, S.N.; Sologub, V.K.; Zabludovskii, A.L.

    1986-06-01

    This paper studies concentrations of Met- and Leu-enkephalins in brain structurers of rats with severe thermal burns in order to elucidate the role of the endogeneous antinociceptive system in the pathogenesis of burn shock. Concentrations of Met- and Leu-enkephalins in the cerebral cortex and hypothalamus were investigated by radioimmunoasay immediattely after burning and 30 min and 2 h later. The hypothalamus of intact rats contained significantly more Metand Leu-enkephalins than the cerebral cortex, but immediately before burning there was a tendency for the Leu-enkephalin concentration in the hypothalamus to rise.

  10. Dopamine release in rat striatum - Physiological coupling to tyrosine supply

    NASA Technical Reports Server (NTRS)

    During, Matthew J.; Acworth, Ian N.; Wurtman, Richard J.

    1989-01-01

    Intracerebral microdialysis was used to monitor dopamine release in rat striatal extracellular fluid following the intraperitoneal administration of dopamine's precursor amino acid, L-tyrosine. Dopamine concentrations in dialysates increased transiently after tyrosine (50-100 mg/kg) administration. Pretreatment with haloperidol or the partial lesioning of nigrostriatal neurons enhanced the effect of tyrosine on dopamine release, and haloperidol also prolonged this effect. These data suggest that nigrostriatal dopaminergic neurons are responsive to changes in precursor availability under basal conditions, but that receptor-mediated feedback mechanisms limit the magnitude and duration of this effect.

  11. Regional differences in endothelin converting enzyme activity in rat brain: inhibition by phosphoramidon and EDTA.

    PubMed Central

    Warner, T. D.; Budzik, G. P.; Matsumoto, T.; Mitchell, J. A.; Förstermann, U.; Murad, F.

    1992-01-01

    1. It has been demonstrated previously that conversion of big endothelin-1 (bET-1) to endothelin-1 (ET-1) is inhibited in vitro and in vivo by phosphoramidon. In addition, ET-1 binding sites and mRNA have been shown within the brain. Here we expand upon our previous observation that rat brain contains phosphoramidon-inhibitable endothelin converting enzyme (ECE) and show that this activity is not uniformly distributed throughout the brain. 2. ECE activity was detected by a bioassay which depended upon the 10,000 fold difference in potency between bET-1 and ET-1 as stimulants of guanosine 3':5'-cyclic monophosphate (cyclic GMP) accumulation in kidney epithelial (PK1) cells of the pig. Data were confirmed by specific enzyme-linked immunosorbent assay (ELISA) employing antibody directed against ET-1/3(17-21). 3. Following homogenization of the whole brain and ultracentrifugation the 100,000 g pellet contained greater than 4 times more ECE activity than the cytosol. Washing of the pellet with KCl (1 M) and extraction with the detergent CHAPS (20 mM) revealed a phosphoramidon-inhibitable ECE within the residual particulate fraction (nominally classified as the cytoskeletal fraction). Phosphoramidon (IC50, approx. 5 microM) or EDTA inhibited the conversion of bET-1 to ET-1 by the cytoskeletal fraction of rat brain by more than 60%.2+ 4. Following dissection of rat brain into olfactory bulb, cerebral cortex, striatum, hippocampus, cerebellum, midbrain (including thalamus), hypothalamus and medulla oblongata (including pons) the greatest ECE was detected in the hypothalamus and medulla oblongata.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1393292

  12. Use of cassette dosing to enhance the throughput of rat brain microdialysis studies.

    PubMed

    Deshmukh, Gauri; Sun, Kefeng; Liederer, Bianca M; Ding, Xiao; Liu, Xingrong

    2015-07-01

    This study was designed to increase the throughput of rat brain microdialysis studies by administration of compounds as a cassette as opposed to discrete study. Eight compounds (carbamazepine, citalopram, desmethylclozapine, diphenhydramine, gabapentin, metoclopramide, naltrexone, and stavudine) were selected and administered as an intravenous bolus dose at 0.5-3.3 mg/kg each followed by an intravenous infusion at 1 mg/kg per hour for 6 hours in rats in a cassette or discrete dosing. The dialysate, plasma, brain, and cerebrospinal fluid were collected and analyzed using liquid chromatography-tandem mass spectrometry. The microdialysis probe recovery was determined by an in vitro gain method. The recovery between the cassette and discrete dosing was similar, with an average of 1.0 ± 0.10-fold difference. The stavudine interstitial fluid (ISF) concentration, as measured by brain microdialysis, was below the low limit of quantitation and was excluded from the analyses. The ratios of ISF concentration to unbound plasma concentration were within 2-fold for six of the remaining seven compounds, with an average of 0.92 ± 0.51-fold difference between the cassette and discrete methods. The ratios of ISF concentration to unbound brain concentration, as measured by the brain homogenate method, were also similar, with a 1.1 ± 0.7-fold difference. In addition, the ratios of ISF to cerebrospinal fluid concentrations were similar, with a 1.5 ± 0.6-fold difference. The results from this study support the use of a cassette dosing approach to enhance the throughput of rat brain microdialysis studies in drug discovery. PMID:25943358

  13. Insights into the role of iron in immature rat model of hypoxic-ischemic brain injury

    PubMed Central

    Wang, Zi-Wei; Yang, Li-Jun; Ding, Ying-Xue; Chang, Yan-Zhong; Cui, Hong

    2016-01-01

    This study aimed to investigate the role of iron in the occurrence and development of hypoxic-ischemic brain injury (HIBI) in immature rat models using 3-day-old Sprague Dawley rats. Normal control (NC), hypoxic-ischemic (HI), anemia, HI + ischemia, early iron treatment and late iron treatment groups were established. Rat brain tissue sections were stained with hematoxylin and eosin and pathologically evaluated. Iron content and mRNA expression levels of iron regulatory protein 2 (IRP2) and transferrin receptor in the brain tissues were measured. Ultrastructural changes in the actin, microtubules, myelin and mitochondria of oligodendrocytes and axons were examined by electron microscopy. Numbers of viable myelin sheaths and oligodendrocytes in the periventricular area were also observed. Pathological damage of brain tissue in the HI group was markedly increased compared with that in the NC group. Furthermore, there was a higher iron content and reduced number of viable oligodendrocytes in the periventricular area of the HI group compared with the NC group. No significant difference in iron content was observed between the HI + anemia and NC groups. The number of viable oligodendrocytes in the HI + anemia group was increased compared with that in the HI group, and the number in the HI + anemia group with late iron treatment was lower compared with that in the NC group and increased compared with that in the HI + anemia group. Electron microscopy revealed a significantly higher number of myelin sheaths in the HI + anemia group than in the HI group. IRP2 mRNA expression levels in the brain tissues were significantly decreased in the HI + anemia group compared with the HI group. The results suggest that anemia may reduce the rate of increase of iron content of the brain following HI. However, the early occurrence of anemia may protect against HIBI. PMID:27602087

  14. Capparis ovata modulates brain oxidative toxicity and epileptic seizures in pentylentetrazol-induced epileptic rats.

    PubMed

    Nazıroğlu, Mustafa; Akay, Mehmet Berk; Çelik, Ömer; Yıldırım, Muhammed İkbal; Balcı, Erdinç; Yürekli, Vedat Ali

    2013-04-01

    It has been widely suggested that oxidative stress products play an important role in the pathophysiology of epilepsy. Capparis ovata (C. ovata) may useful treatment of epilepsy because it contains antioxidant flavonoids. The current study was designed to determine the effects of C. ovata on lipid peroxidation, antioxidant levels and electroencephalography (EEG) records in pentylentetrazol (PTZ)-induced epileptic rats. Thirty-two rats were randomly divided into four groups. First group was used as control although second group was PTZ group. Oral 100 and 200 mg/kg C. ovata were given to rats constituting the third and fourth groups for 7 days before PTZ administration. Second, third and forth groups received 60 mg/kg PTZ for induction of epilepsy. Three hours after administration of PTZ, EEG records, brain cortex and blood samples were taken all groups. The lipid peroxidation levels of the brain cortex, number of spikes and epileptiform discharges of EEG were higher in PTZ group than in control and C. ovata group whereas they were decreased by C. ovata administration. Vitamin A, vitamin C, vitamin E and β-carotene concentrations of brain cortex and latency to first spike of EEG were decreased by the PTZ administration although the brain cortex and plasma vitamin concentrations, and brain cortex and erythrocyte glutathione and glutathione peroxidase values were increased in PTZ + 100 and PTZ + 200 mg C. ovata groups. In conclusion, C. ovata administration caused protection against the PTZ-induced brain oxidative toxicity by inhibiting free radical and epileptic seizures, and supporting antioxidant redox system. PMID:23389657

  15. Human and rat glioma growth, invasion, and vascularization in a novel chick embryo brain tumor model.

    PubMed

    Cretu, Alexandra; Fotos, Joseph S; Little, Brian W; Galileo, Deni S

    2005-01-01

    The mechanisms that control the insidiously invasive nature of malignant gliomas are poorly understood, and their study would be facilitated by an in vivo model that is easy to manipulate and inexpensive. The developing chick embryo brain was assessed as a new xenograft model for the production, growth, and study of human and rat glioma cell lines. Three established glioma lines (U-87 MG, C6, and 9L) were injected into chick embryo brain ventricles on embryonic day (E) 5 and brains were examined after several days to two weeks after injection. All glioma lines survived, produced vascularized intraventricular tumors, and invaded the brain in a manner similar to that in rodents. Rat C6 glioma cells spread along vasculature and also invaded the neural tissue. Human U-87 glioma cells migrated along vasculature and exhibited slight invasion of neural tissue. Rat 9L gliosarcoma cells were highly motile, but migrated only along the vasculature. A derivative of 9L cells that stably expressed the cell surface adhesion molecule NgCAM/L1 was produced and also injected into chick embryo brain ventricles to see if this protein could facilitate tumor cell migration away from the vasculature into areas such as axonal tracts. 9L/NgCAM cells, however, did not migrate away from the vasculature and, thus, this protein alone cannot be responsible for diffuse invasiveness of some gliomas. 9L/NgCAM cell motility was assessed in vitro using sophisticated time-lapse microscopy and quantitative analysis, and was significantly altered compared to parental 9L cells. These studies demonstrate that the chick embryo brain is a successful and novel xenograft model for mammalian gliomas and demonstrate the potential usefulness of this new model for studying glioma tumor cell growth, vascularization, and invasiveness. PMID:16158250

  16. Sexually dimorphic alterations of brain cortical dominance in rats prenatally exposed to TCDD.

    PubMed

    Zareba, Grazyna; Hojo, Rieko; Zareba, Karolina M; Watanabe, Chiho; Markowski, Vincent P; Baggs, Raymond B; Weiss, Bernard

    2002-01-01

    Sexually dimorphic patterns of cortical lateralization are documented extensively in both human and animal brains. Male rats tend to exhibit pronounced right hemisphere dominance compared with females, whereas females typically exhibit more diffuse lateralization patterns and greater left hemisphere bias compared with males. Prenatal TCDD (2,3,7,8 tetrachlorodibenzo-p-dioxin) exposure produces demasculinization of male offspring sexual behavior. In previous studies, we showed a reversal of cortical dominance in rats after prenatal TCDD exposure on gestational day 18 (GD 18). The current study aimed to determine the nature of changes observed in rats exposed to TCDD on GD 8. In addition, locomotor activity was measured in male and female offspring on postnatal day (PND) 30, 60 and 90. Pregnant females were given, via gavage, a single dose of 0, 20, 60 or 180 ng kg(-1) TCDD on GD 8. Cortical depth measurements were taken in selected brain regions in offspring 3 months old that had been exposed to the 180 ng kg(-1) dose. Areas 2, 3, 17, 18a and 39 at bregmas -1.8, -3.8 and -5.8 were analyzed by quantifying digitized, enhanced images produced by a photomicroscope fitted with a special color camera. In both male and female offspring, cortical thicknesses in control brains exceeded those of exposed brains. In several brain areas of male offspring exposed to TCDD, right hemispheric dominance reversed to left hemispheric dominance. Female offspring brains showed a contrary move towards right hemisphere dominance. Motor activity in juvenile and mature animals did not differ among dose groups. These data demonstrate that prenatal exposure to TCDD reduces cortical thickness and alters the normal pattern of cortical asymmetry, a finding consistent with the sexually dimorphic behavioral effects induced by this agent. PMID:11920938

  17. Spatial properties of astrocyte gap junction coupling in the rat hippocampus

    PubMed Central

    Anders, Stefanie; Minge, Daniel; Griemsmann, Stephanie; Herde, Michel K.; Steinhäuser, Christian; Henneberger, Christian

    2014-01-01

    Gap junction coupling enables astrocytes to form large networks. Its strength determines how easily a signalling molecule diffuses through the network and how far a locally initiated signal can spread. Changes of coupling strength are well-documented during development and in response to various stimuli. Precise quantification of coupling is needed for studying such modifications and their functional consequences. We therefore explored spatial properties of astrocyte coupling in a model simulating dye loading of single astrocytes. Dye spread into the astrocyte network could be characterized by a coupling length constant and coupling anisotropy. In experiments, the fluorescent marker Alexa Fluor 594 was used to measure these parameters in CA1 and dentate gyrus of the rat hippocampus. Coupling did not differ between regions but showed a temperature-dependence, partially owing to changes of intracellular diffusivity, detected by measuring coupling length constants but not the more variable cell counts of dye-coupled astrocytes. We further found that coupling is anisotropic depending on distance to the pyramidal cell layer, which correlated with regional differences of astrocyte morphology. This demonstrates that applying these new analytical approaches provides useful quantitative information on gap junction coupling and its heterogeneity. PMID:25225094

  18. Spatial properties of astrocyte gap junction coupling in the rat hippocampus.

    PubMed

    Anders, Stefanie; Minge, Daniel; Griemsmann, Stephanie; Herde, Michel K; Steinhäuser, Christian; Henneberger, Christian

    2014-10-19

    Gap junction coupling enables astrocytes to form large networks. Its strength determines how easily a signalling molecule diffuses through the network and how far a locally initiated signal can spread. Changes of coupling strength are well-documented during development and in response to various stimuli. Precise quantification of coupling is needed for studying such modifications and their functional consequences. We therefore explored spatial properties of astrocyte coupling in a model simulating dye loading of single astrocytes. Dye spread into the astrocyte network could be characterized by a coupling length constant and coupling anisotropy. In experiments, the fluorescent marker Alexa Fluor 594 was used to measure these parameters in CA1 and dentate gyrus of the rat hippocampus. Coupling did not differ between regions but showed a temperature-dependence, partially owing to changes of intracellular diffusivity, detected by measuring coupling length constants but not the more variable cell counts of dye-coupled astrocytes. We further found that coupling is anisotropic depending on distance to the pyramidal cell layer, which correlated with regional differences of astrocyte morphology. This demonstrates that applying these new analytical approaches provides useful quantitative information on gap junction coupling and its heterogeneity. PMID:25225094

  19. Nonlinear accumulation in the brain of the new taxoid TXD258 following saturation of P-glycoprotein at the blood–brain barrier in mice and rats

    PubMed Central

    Cisternino, Salvatore; Bourasset, Fanchon; Archimbaud, Yves; Sémiond, Dorothée; Sanderink, Gérard; Scherrmann, Jean-Michel

    2003-01-01

    TXD258, a new taxoid antitumor agent, is a poor substrate for the P-glycoprotein (P-gp) in Caco-2 cells. In this study, we investigated the amount of drug accumulating in the brains of rats and mice under a variety of conditions (dose and infusion time, species and plasma concentration) using conventional in vivo pharmacokinetic techniques and in situ brain perfusion. Mice were infused with radiolabeled TXD258 at 15, 30, 45 and 90 mg m−2 for 45 s or 1 h and rats were infused with 15 and 60 mg m−2 over 2.3 min. The radioactivity in the plasma and brains was measured. The brain concentrations of TXD258 in mice and rats were maximal from 2 min to 1 h postinfusion and radioactivity was still detectable at 168 h. While the plasma concentration of TXD258 increased linearly in mice with the infused dose, the brain content increased more than proportionally with the dose between 15 and 90 mg m−2. This nonlinear uptake of TXD258 also occurred in the plasma and brain of the rat. These findings suggest that the protein-mediated efflux across the blood–brain barrier (BBB) becomes saturated. In situ brain perfusion studies confirmed that TXD258 is a P-gp substrate at the BBB of mice and rats. The P-gp of both species was saturated at the half-inhibitory concentration (∼13 μM) produced by i.v. infusion. Thus, the observed nonlinear accumulation of TXD258 in the brain seems to occur by saturation of the P-gp at the rodent BBB. This saturation could have several advantages, such as overcoming a P-gp-mediated efflux, but the nonlinear pharmacokinetics could increase the risk of toxicity. PMID:12711638

  20. Physical training decreases susceptibility to pilocarpine-induced seizures in the injured rat brain.

    PubMed

    Setkowicz, Zuzanna; Kosonowska, Emilia; Kaczyńska, Małgorzata; Gzieło-Jurek, Kinga; Janeczko, Krzysztof

    2016-07-01

    There is growing evidence that physical activity ameliorates the course of epilepsy in animal models as well as in clinical conditions. Since traumatic brain injury is one of the strongest determinants of epileptogenesis, the present study focuses on the question whether a moderate long-term physical training can decrease susceptibility to seizures evoked following brain damage. Wistar rats received a mechanical brain injury and were subjected to daily running sessions on a treadmill for 21 days. Thereafter, seizures were induced by pilocarpine injections in trained and non-trained, control groups. During the acute period of status epilepticus, the intensity of seizures was assessed within the six-hour observation period. The trained rats showed considerable amelioration of pilocarpine-induced motor symptoms when compared with their non-trained counterparts. Histological investigations of effects of the brain injury and of physical training detected significant quantitative changes in parvalbumin-, calretinin- and NPY-immunopositive neuronal populations. Some of the injury-induced changes, especially those shoved by parvalbumin-immunopositive neurons, were abolished by the subsequent physical training procedure and could, therefore, be considered as neuronal correlates of the observed functional amelioration of the injured brain. PMID:26972533

  1. Unilateral Opening of Rat Blood-Brain Barrier Assisted by Diagnostic Ultrasound Targeted Microbubbles Destruction.

    PubMed

    Xu, Yali; Cui, Hai; Zhu, Qiong; Hua, Xing; Xia, Hongmei; Tan, Kaibin; Gao, Yunhua; Zhao, Jing; Liu, Zheng

    2016-01-01

    Objective. Blood-brain barrier (BBB) is a key obstacle that prevents the medication from blood to the brain. Microbubble-enhanced cavitation by focused ultrasound can open the BBB and proves to be valuable in the brain drug delivery. The study aimed to explore the feasibility, efficacy, and safety of unilateral opening of BBB using diagnostic ultrasound targeted microbubbles destruction in rats. Methods. A transtemporal bone irradiation of diagnostic ultrasound and intravenous injection of lipid-coated microbubbles were performed at unilateral hemisphere. Pathological changes were monitored. Evans Blue extravasation grades, extraction from brain tissue, and fluorescence optical density were quantified. Lanthanum nitrate was traced by transmission electron microscopy. Results. After diagnostic ultrasound mediated microbubbles destruction, Evans Blue extravasation and fluorescence integrated optical density were significantly higher in the irradiated hemisphere than the contralateral side (all p < 0.01). Erythrocytes extravasations were demonstrated in the ultrasound-exposed hemisphere (4 ± 1, grade 2) while being invisible in the control side. Lanthanum nitrate tracers leaked through interendothelial cleft and spread to the nerve fiber existed in the irradiation side. Conclusions. Transtemporal bone irradiation under DUS mediated microbubble destruction provides us with a more accessible, safer, and higher selective BBB opening approach in rats, which is advantageous in brain targeted drugs delivery. PMID:27579317

  2. Dexamethasone and betamethasone protect against LPS-induced brain damage in the neonatal rats

    PubMed Central

    Pang, Yi; Fan, Lir-Wan; Zheng, Baoying; Campbell, Leigh R.; Cai, Zhengwei; Rhodes, Philip G.

    2013-01-01

    The aim of this study is to test whether dexamethasone (Dex) and betamethasone (Beta), two of the most commonly used corticosteroids, protect against lipopolysaccharide (LPS)-induced white matter damage and neurobehavioral dysfunction. LPS or sterile saline was injected into the brain white matter of rat pups at postnatal day 5 (P5) and Dex or Beta was given intraperitoneally to the rat pups 1 h before the LPS microinjection. Brain inflammatory response, brain damage, and myelination were examined at P6, P8 and P14. Neurobehavioral tests were performed from P3 through P22. Our results demonstrate that Dex and Beta markedly diminish the LPS-induced brain inflammatory response, restore myelin basic protein (MBP) expression and alleviate lateral ventricle dilation. Both corticosteroids demonstrate significant protection against most of LPS-induced behavioral deficits, including those in rearing, vibrissa-elicited forelimb-placing, beam walking, learning and elevated plus-maze test. Notably, only Beta improved the locomotion and stereotype dysfunction. In contrast to their beneficial effects, neither drug prevented LPS-induced delay in body weight gain from P6 through P21. Our study suggests that if their adverse effects are minimized, corticosteroids may be the potential candidate drugs to prevent brain damage in premature infants. PMID:22314662

  3. Cerebral and extracerebral vulnerability to hypoxic insults after diffuse traumatic brain injury in rats.

    PubMed

    Mrozek, Ségolène; Luzi, Aymeric; Gonzalez, Leslie; Kerhuel, Lionel; Fourcade, Olivier; Geeraerts, Thomas

    2016-09-01

    The post-traumatic brain vulnerability suggests that after traumatic brain injury (TBI), the brain may be more susceptible to posttraumatic hypoxic insults. This concept could be extended to 'peripheral' organs, as non-neurologic organ failure is common after TBI. This study aims to characterize and quantify cerebral and extracerebral tissue hypoxia with pimonidazole resulting from a standardized hypoxia-hypotension (HH) phase occurring after a diffuse experimental TBI in rats. Rats were allocated to Sham (n=5), TBI (n=7), HH (n=7) and TBI+HH (n=7) groups. Then, pimonidazole was injected and brain, liver, heart and kidneys were analysed. In the cerebral cortex, post-treatment hypoxia was higher in TBI+HH group than Sham group (p=0.003), HH group (p=0.003) and TBI group (p=0.002). Large trends in thalamus, hippocampus and striatum for the TBI+HH group compared to the other groups were observed. For the heart and liver, the 4 groups were comparable. For the kidneys, post-treatment hypoxia was higher in the TBI group compared to the Sham and HH groups, but not more than TBI+HH group. This study reveals that a posttraumatic hypoxic insult occurring after a severe TBI has major hypoxic consequences on brain structures. However, TBI by itself appears to induce renal hypoxia that is not enhanced by posttraumatic hypoxic insult. PMID:27302136

  4. Unilateral Opening of Rat Blood-Brain Barrier Assisted by Diagnostic Ultrasound Targeted Microbubbles Destruction

    PubMed Central

    Cui, Hai; Zhu, Qiong; Hua, Xing; Xia, Hongmei; Tan, Kaibin; Gao, Yunhua; Zhao, Jing

    2016-01-01

    Objective. Blood-brain barrier (BBB) is a key obstacle that prevents the medication from blood to the brain. Microbubble-enhanced cavitation by focused ultrasound can open the BBB and proves to be valuable in the brain drug delivery. The study aimed to explore the feasibility, efficacy, and safety of unilateral opening of BBB using diagnostic ultrasound targeted microbubbles destruction in rats. Methods. A transtemporal bone irradiation of diagnostic ultrasound and intravenous injection of lipid-coated microbubbles were performed at unilateral hemisphere. Pathological changes were monitored. Evans Blue extravasation grades, extraction from brain tissue, and fluorescence optical density were quantified. Lanthanum nitrate was traced by transmission electron microscopy. Results. After diagnostic ultrasound mediated microbubbles destruction, Evans Blue extravasation and fluorescence integrated optical density were significantly higher in the irradiated hemisphere than the contralateral side (all p < 0.01). Erythrocytes extravasations were demonstrated in the ultrasound-exposed hemisphere (4 ± 1, grade 2) while being invisible in the control side. Lanthanum nitrate tracers leaked through interendothelial cleft and spread to the nerve fiber existed in the irradiation side. Conclusions. Transtemporal bone irradiation under DUS mediated microbubble destruction provides us with a more accessible, safer, and higher selective BBB opening approach in rats, which is advantageous in brain targeted drugs delivery. PMID:27579317

  5. C/EBPβ Isoforms Expression in the Rat Brain during the Estrous Cycle

    PubMed Central

    Hansberg-Pastor, Valeria; Piña-Medina, Ana Gabriela; González-Arenas, Aliesha; Camacho-Arroyo, Ignacio

    2015-01-01

    The CCAAT/enhancer-binding protein beta (C/EBPβ) is a transcription factor expressed in different areas of the brain that regulates the expression of several genes involved in cell differentiation and proliferation. This protein has three isoforms (LAP1, LAP2, and LIP) with different transcription activation potential. The role of female sex hormones in the expression pattern of C/EBPβ isoforms in the rat brain has not yet been described. In this study we demonstrate by western blot that the expression of the three C/EBPβ isoforms changes in different brain areas during the estrous cycle. In the cerebellum, LAP2 content diminished on diestrus and proestrus and LIP content diminished on proestrus and estrus days. In the prefrontal cortex, LIP content was higher on proestrus and estrus days. In the hippocampus, LAP isoforms presented a switch on diestrus day, since LAP1 content was the highest while that of LAP2 was the lowest. The LAP2 isoform was the most abundant one in all the three brain areas. The LAP/LIP ratio changed throughout the cycle and was tissue specific. These results suggest that C/EBPβ isoforms expression changes in a tissue-specific manner in the rat brain due to the changes in sex steroid hormone levels presented during the estrous cycle. PMID:26064112

  6. Treatment of penetrating brain injury in a rat model using collagen scaffolds incorporating soluble Nogo receptor.

    PubMed

    Elias, Paul Z; Spector, Myron

    2015-02-01

    Injuries and diseases of the central nervous system (CNS) have the potential to cause permanent loss of brain parenchyma, with severe neurological consequences. Cavitary defects in the brain may afford the possibility of treatment with biomaterials that fill the lesion site while delivering therapeutic agents. This study examined the treatment of penetrating brain injury (PBI) in a rat model with collagen biomaterials and a soluble Nogo receptor (sNgR) molecule. sNgR was aimed at neutralizing myelin proteins that hinder axon regeneration by inducing growth cone collapse. Scaffolds containing sNgR were implanted in the brains of adult rats 1 week after injury and analysed 4 weeks or 8 weeks later. Histological analysis revealed that the scaffolds filled the lesion sites, remained intact with open pores and were infiltrated with cells and extracellular matrix. Immunohistochemical staining demonstrated the composition of the cellular infiltrate to include macrophages, astrocytes and vascular endothelial cells. Isolated regions of the scaffold borders showed integration with surrounding viable brain tissue that included neurons and oligodendrocytes. While axon regeneration was not detected in the scaffolds, the cellular infiltration and vascularization of the lesion site demonstrated a modification of the injury environment with implications for regenerative strategies. PMID:23038669

  7. Effects of the administration routes and chemical forms of aluminum on aluminum accumulation in rat brain.

    PubMed

    Ogasawara, Yuki; Sakamoto, Takashi; Ishii, Kazuyuki; Takahashi, Hidenobu; Tanabe, Shinzo

    2002-06-01

    An experimental rat model of aluminum accumulation in the brain was developed to aid in determining neurotoxity of aluminum (Al). Al was administered orally, intravenously, and intraperitoneally, in the absence or presence of citric acid or maltol. Oral administration of Al hydroxide [Al (OH)3] or aluminum chloride (AlC13) with citric acid for 7 wk was not found to increase brain Al levels. Similarly, a single intravenous injection of AlCl3 in the presence or absence of either citric acid or maltol did not alter brain Al levels after 48 h. Only daily intraperitoneal injections of AlC13 (8 mg Al/kg body weight) and an equimolar amount of maltol over a 14-d period enhanced accumulation of Al in rat brain. No significant increases were observed for the experimental groups receiving intraperitoneal AlCl3 alone or with citric acid. This result suggests that the chemical form of Al strongly influences its bioavailability and that intraperitoneal administration of the Al-maltol complex appears to be useful in creating subacute model of Al accumulation in brain tissue. PMID:12019523

  8. Early embryonic brain development in rats requires the trophic influence of cerebrospinal fluid.

    PubMed

    Martin, C; Alonso, M I; Santiago, C; Moro, J A; De la Mano, A; Carretero, R; Gato, A

    2009-11-01

    Cerebrospinal fluid has shown itself to be an essential brain component during development. This is particularly evident at the earliest stages of development where a lot of research, performed mainly in chick embryos, supports the evidence that cerebrospinal fluid is involved in different mechanisms controlling brain growth and morphogenesis, by exerting a trophic effect on neuroepithelial precursor cells (NPC) involved in controlling the behaviour of these cells. Despite it being known that cerebrospinal fluid in mammals is directly involved in corticogenesis at fetal stages, the influence of cerebrospinal fluid on the activity of NPC at the earliest stages of brain development has not been demonstrated. Here, using "in vitro" organotypic cultures of rat embryo brain neuroepithelium in order to expose NPC to or deprive them of cerebrospinal fluid, we show that the neuroepithelium needs the trophic influence of cerebrospinal fluid to undergo normal rates of cell survival, replication and neurogenesis, suggesting that NPC are not self-sufficient to induce their normal activity. This data shows that cerebrospinal fluid is an essential component in chick and rat early brain development, suggesting that its influence could be constant in higher vertebrates. PMID:19540909

  9. Decreased Resting Functional Connectivity after Traumatic Brain Injury in the Rat

    PubMed Central

    Mishra, Asht Mangal; Bai, Xiaoxiao; Sanganahalli, Basavaraju G.; Waxman, Stephen G.; Shatillo, Olena; Grohn, Olli; Hyder, Fahmeed; Pitkänen, Asla; Blumenfeld, Hal

    2014-01-01

    Traumatic brain injury (TBI) contributes to about 10% of acquired epilepsy. Even though the mechanisms of post-traumatic epileptogenesis are poorly known, a disruption of neuronal networks predisposing to altered neuronal synchrony remains a viable candidate mechanism. We tested a hypothesis that resting state BOLD-fMRI functional connectivity can reveal network abnormalities in brain regions that are connected to the lesioned cortex, and that these changes associate with functional impairment, particularly epileptogenesis. TBI was induced using lateral fluid-percussion injury in seven adult male Sprague-Dawley rats followed by functional imaging at 9.4T 4 months later. As controls we used six sham-operated animals that underwent all surgical operations but were not injured. Electroencephalogram (EEG)-functional magnetic resonance imaging (fMRI) was performed to measure resting functional connectivity. A week after functional imaging, rats were implanted with bipolar skull electrodes. After recovery, rats underwent pentyleneterazol (PTZ) seizure-susceptibility test under EEG. For image analysis, four pairs of regions of interests were analyzed in each hemisphere: ipsilateral and contralateral frontal and parietal cortex, hippocampus, and thalamus. High-pass and low-pass filters were applied to functional imaging data. Group statistics comparing injured and sham-operated rats and correlations over time between each region were calculated. In the end, rats were perfused for histology. None of the rats had epileptiform discharges during functional imaging. PTZ-test, however revealed increased seizure susceptibility in injured rats as compared to controls. Group statistics revealed decreased connectivity between the ipsilateral and contralateral parietal cortex and between the parietal cortex and hippocampus on the side of injury as compared to sham-operated animals. Injured animals also had abnormal negative connectivity between the ipsilateral and contralateral

  10. Chloride permeability of rat brain membrane vesicles correlates with thiamine triphosphate content.

    PubMed

    Bettendorff, L; Hennuy, B; De Clerck, A; Wins, P

    1994-07-25

    Incubation of rat brain homogenates with thiamine or thiamine diphosphate (TDP) leads to a synthesis of thiamine triphosphate (TTP). In membrane vesicles subsequently prepared from the homogenates, increased TTP content correlates with increased 36Cl- uptake. A hyperbolic relationship was obtained with a K0.5 of 0.27 nmol TTP/mg protein. In crude mitochondrial fractions from the brains of animals previously treated with thiamine or sulbutiamine, a positive correlation between 36Cl- uptake and TTP content was found. These results, together with other results previously obtained with the patch-clamp technique, suggest that TTP is an activator of chloride channels having a large unit conductance. PMID:7953714

  11. Simulated ischaemia-reperfusion conditions increase xanthine dehydrogenase and oxidase activities in rat brain slices.

    PubMed

    Battelli, M G; Buonamici, L; Virgili, M; Abbondanza, A; Contestabile, A

    1998-01-01

    Xanthine dehydrogenase and oxidase activities increased by 87% in rat brain slices after 30 min in vitro ischaemia. A further 41% increase was induced by 30 min simulated reperfusion of ischaemic slices. No conversion from the dehydrogenase to the oxidase activity was observed. The increment of enzyme activity was not due to neosynthesis of the enzyme, since it was not affected by the addition of cycloheximide during the ischaemic incubation. The increased oxygen-dependent form of the enzyme could aggravate the ischaemic brain injury by free radicals production, in particular after reperfusion. PMID:9460697

  12. Effects on operant learning and brain acetylcholine esterase activity in rats following chronic inorganic arsenic intake.

    PubMed

    Nagaraja, T N; Desiraju, T

    1994-05-01

    1. Very young and adult Wistar rats were given As5+, 5 mg arsenic kg-1 body weight day-1 (sodium arsenate). 2. Operant learning was tested in a Skinner box at the end of exposure and, in the case of developing animals, also after a recovery period. 3. Acetylcholine esterase (AChE) activity was estimated in discrete brain regions of these animals. 4. The animals exposed to arsenic took longer to acquire the learned behaviour and to extinguish the operant. AChE activity was inhibited in some regions of the brain. PMID:8043317

  13. EFFECT OF REPEATED ORGANOPHOSPHATE ADMINISTRATION ON CARBACHOL-STIMULATED PHOSPHOINSITIDE HYDROLYSIS IN RAT BRAIN

    EPA Science Inventory

    The effects of repeated exposure to two organophosphates on the turnover of phosphoinositides, the second messenger system coupled to the M1 and M3 subtypes of muscarinic receptors, were examined in rat hippocampus. epeated diisopropylfluorophosphate (DFP) exposure (0.2-0.8 mg/kg...

  14. Linear Gadolinium-Based Contrast Agents Are Associated With Brain Gadolinium Retention in Healthy Rats

    PubMed Central

    Robert, Philippe; Violas, Xavier; Grand, Sylvie; Lehericy, Stéphane; Idée, Jean-Marc; Ballet, Sébastien; Corot, Claire

    2016-01-01

    Objectives The aim of this study was to evaluate Gd retention in the deep cerebellar nuclei (DCN) of linear gadolinium-based contrast agents (GBCAs) compared with a macrocyclic contrast agent. Materials and Methods The brain tissue retention of Gd of 3 linear GBCAs (gadobenate dimeglumine, gadopentetate dimeglumine, and gadodiamide) and a macrocyclic GBCA (gadoterate meglumine) was compared in healthy rats (n = 8 per group) that received 20 intravenous injections of 0.6 mmol Gd/kg (4 injections per week for 5 weeks). An additional control group with saline was included. T1-weighted magnetic resonance imaging was performed before injection and once a week during the 5 weeks of injections and for another 4 additional weeks after contrast period. Total gadolinium concentration was measured with inductively coupled plasma mass spectrometry. Blinded qualitative and quantitative evaluations of the T1 signal intensity in DCN were performed, as well as a statistical analysis on quantitative data. Results At completion of the injection period, all the linear contrast agents (gadobenate dimeglumine, gadopentetate dimeglumine, and gadodiamide) induced a significant increase in signal intensity in DCN, unlike the macrocyclic GBCA (gadoterate meglumine) or saline. The T1 hypersignal enhancement kinetic was fast for gadodiamide. Total Gd concentrations for the 3 linear GBCAs groups at week 10 were significantly higher in the cerebellum (1.21 ± 0.48, 1.67 ± 0.17, and 3.75 ± 0.18 nmol/g for gadobenate dimeglumine, gadopentetate dimeglumine, and gadodiamide, respectively) than with the gadoterate meglumine (0.27 ± 0.16 nmol/g, P < 0.05) and saline (0.09 ± 0.12 nmol/g, P < 0.05). No significant difference was observed between the macrocyclic agent and saline. Conclusions Repeated administrations of the linear GBCAs gadodiamide, gadobenate dimeglumine, and gadopentetate dimeglumine to healthy rats were associated with progressive and significant T1 signal hyperintensity in the

  15. Age-dependent increase of etheno-DNA-adducts in liver and brain of ROS overproducing OXYS rats

    SciTech Connect

    Nair, Jagadeesan; Sinitsina, Olga; Vasunina, Elena A.; Nevinsky, Georgy A.; Laval, Jacques; Bartsch, Helmut . E-mail: h.bartsch@dkfz.de

    2005-10-21

    Reactive oxygen species (ROS) and lipid peroxidation (LPO) play a role in aging and degenerative diseases. To correlate oxidative stress and LPO-derived DNA damage, we determined etheno-DNA-adducts in liver and brain from ROS overproducing OXYS rats in comparison with age-matched Wistar rats. Liver DNA samples from 3- and 15-month-old OXYS and Wistar rats were analyzed for 1,N {sup 6}-ethenodeoxyadenosine ({epsilon}dA) and 3,N {sup 4}-ethenodeoxycytidine ({epsilon}dC) by immunoaffinity/{sup 32}P-postlabelling. While {epsilon}dA and {epsilon}dC levels were not different in young rats, adduct levels were significantly higher in old OXYS rats when compared to old Wistar or young OXYS rats. Frozen rat brain sections were analyzed for {epsilon}dA by immunostaining of nuclei. Brains from old OXYS rats accumulated {epsilon}dA more frequently than age-matched Wistar rats. Our results demonstrate increased LPO-induced DNA damage in organs of OXYS rats which correlates with their known shorter life-span and elevated frequency of chronic degenerative diseases.

  16. Volume regulatory loss of Na, Cl, and K from rat brain during acute hyponatremia

    SciTech Connect

    Melton, J.E.; Patlak, C.S.; Pettigrew, K.D.; Cserr, H.F.

    1987-04-01

    This study quantitatively evaluates the contribution of tissue Na, Cl, and K loss to brain volume regulation during acute dilutional hyponatremia (DH) and examines the mechanism of Na loss. DH was produced in pentobarbital sodium-anesthetized rats by intraperitoneal infusion of distilled water and brain water and electrolytes analyzed 30 min, 1 h, 3 h, 4 h, or 6 h later. The rate of Na and Cl loss was greatest during the first 30 min of DH. Net loss of Na and Cl was maximal after 3 h of DH. K loss was slower, achieving significance after 3 h. Electrolyte loss was sufficient to account for observed brain volume regulation after three or more hours of DH. Measurements of /sup 22/Na influx and efflux across the blood brain barrier showed that barrier permeability to Na is unchanged during DH. Analysis of results using a two-compartment model of plasma-brain exchange suggests that loss of brain Na during DH does not result solely from a shift of electrolyte across the blood-brain barrier to plasma, and thus provides indirect evidence for an additional pathway for Na loss, presumably via cerebrospinal fluid.

  17. Workflow and atlas system for brain-wide mapping of axonal connectivity in rat.

    PubMed

    Zakiewicz, Izabela M; van Dongen, Yvette C; Leergaard, Trygve B; Bjaalie, Jan G

    2011-01-01

    Detailed knowledge about the anatomical organization of axonal connections is important for understanding normal functions of brain systems and disease-related dysfunctions. Such connectivity data are typically generated in neuroanatomical tract-tracing experiments in which specific axonal connections are visualized in histological sections. Since journal publications typically only accommodate restricted data descriptions and example images, literature search is a cumbersome way to retrieve overviews of brain connectivity. To explore more efficient ways of mapping, analyzing, and sharing detailed axonal connectivity data from the rodent brain, we have implemented a workflow for data production and developed an atlas system tailored for online presentation of axonal tracing data. The system is available online through the Rodent Brain WorkBench (www.rbwb.org; Whole Brain Connectivity Atlas) and holds experimental metadata and high-resolution images of histological sections from experiments in which axonal tracers were injected in the primary somatosensory cortex. We here present the workflow and the data system, and exemplify how the online image repository can be used to map different aspects of the brain-wide connectivity of the rat primary somatosensory cortex, including not only presence of connections but also morphology, densities, and spatial organization. The accuracy of the approach is validated by comparing results generated with our system with findings reported in previous publications. The present study is a contribution to a systematic mapping of rodent brain connections and represents a starting point for further large-scale mapping efforts. PMID:21829640

  18. Dynamic effects of point source electroporation on the rat brain tissue.

    PubMed

    Sharabi, Shirley; Last, David; Guez, David; Daniels, Dianne; Hjouj, Mohammad Ibrahim; Salomon, Sharona; Maor, Elad; Mardor, Yael

    2014-10-01

    In spite of aggressive therapy, existing treatments offer poor prognosis for glioblastoma multiforme due to tumor infiltration into the surrounding brain as well as poor blood-brain barrier penetration of most therapeutic agents. In this paper we present a novel approach for a minimally invasive treatment and a non-invasive response assessment methodology consisting of applying intracranial point-source electroporation and assessing treatment effect volumes using magnetic resonance imaging. Using a unique setup of a single intracranial electrode and an external surface electrode we treated rats' brains with various electroporation protocols and applied magnetic resonance imaging to study the dependence of the physiological effects on electroporation treatment parameters. The extent of blood-brain barrier disruption and later volumes of permanent brain tissue damage were found to correlate significantly with the treatment voltages (r(2)=0.99, p<0.001) and the number of treatment pulses (r(2)=0.94, p<0.002). Blood-brain barrier disruption depicted 3.2±0.3 times larger volumes than the final permanent damage volumes (p<0.0001). These results indicate that it may be beneficial to use more than one modality of electroporation when planning a treatment for brain tumors. PMID:24976141

  19. Effects of single-dose and fractionated cranial irradiation on rat brain accumulation of methotrexate

    SciTech Connect

    Kamen, B.A.; Moulder, J.E.; Kun, L.E.; Ring, B.J.; Adams, S.M.; Fish, B.L.; Holcenberg, J.S.

    1984-11-01

    The effects of single-dose and fractionated whole-brain irradiation on brain methotrexate (MTX) has been studied in a rat model. The amount of MTX present in the brain 24 hr after a single i.p. dose (100 mg/kg) was the same whether animals were sham irradiated or given a single dose of 2000 rads 6 or 48 hr prior to the drug (6.9, 8.3, and 6.8 pmol MTX/g, wet weight, respectively). Animals sham irradiated or given 2000 rads in 10 fractions over 11 days and treated with an average dose of 1.2 mg MTX/kg i.p. twice a week for 24 weeks did not differ significantly in their brain MTX concentration (7.9 and 8.3 pmol MTX/g, wet weight, respectively). Chronically MTX-treated animals became folate deficient whether they were irradiated or not (450 and 670 pmol folate/g, wet weight, brain in MTX-treated and control animals). Thus, MTX accumulates in the brain with acute or chronic administration, and this accumulation is not altered by this amount of brain irradiation.

  20. Glial response to 17β-estradiol in neonatal rats with excitotoxic brain injury.

    PubMed

    Pansiot, Julien; Pham, Hoa; Dalous, Jeremie; Chevenne, Didier; Colella, Marina; Schwendimann, Leslie; Fafouri, Assia; Mairesse, Jérôme; Moretti, Raffaella; Schang, Anne-Laure; Charriaut-Marlangue, Christiane; Gressens, Pierre; Baud, Olivier

    2016-08-01

    White-matter injury is the most common cause of the adverse neurodevelopmental outcomes observed in preterm infants. Only few options exist to prevent perinatal brain injury associated to preterm delivery. 17β-estradiol (E2) is the predominant estrogen in circulation and has been shown to be neuroprotective in vitro and in vivo. However, while E2 has been found to modulate inflammation in adult models of brain damage, how estrogens influence glial cells response in the developing brain needs further investigations. Using a model of ibotenate-induced brain injury, we have refined the effects of E2 in the developing brain. E2 provides significant neuroprotection both in the cortical plate and the white matter in neonatal rats subjected to excitotoxic insult mimicking white matter and cortical damages frequently observed in very preterm infants. E2 promotes significant changes in microglial phenotypes balance in response to brain injury and the acceleration of oligodendrocyte maturation. Maturational effects of E2 on myelination process were observed both in vivo and in vitro. Altogether, these data demonstrate that response of glial cells to E2 could be responsible for its neuroprotective properties in neonatal excitotoxic brain injury. PMID:27222132

  1. Restraint Stress-Induced Morphological Changes at the Blood-Brain Barrier in Adult Rats

    PubMed Central

    Sántha, Petra; Veszelka, Szilvia; Hoyk, Zsófia; Mészáros, Mária; Walter, Fruzsina R.; Tóth, Andrea E.; Kiss, Lóránd; Kincses, András; Oláh, Zita; Seprényi, György; Rákhely, Gábor; Dér, András; Pákáski, Magdolna; Kálmán, János; Kittel, Ágnes; Deli, Mária A.

    2016-01-01

    Stress is well-known to contribute to the development of both neurological and psychiatric diseases. While the role of the blood-brain barrier is increasingly recognized in the development of neurodegenerative disorders, such as Alzheimer's disease, dysfunction of the blood-brain barrier has been linked to stress-related psychiatric diseases only recently. In the present study the effects of restraint stress with different duration (1, 3, and 21 days) were investigated on the morphology of the blood-brain barrier in male adult Wistar rats. Frontal cortex and hippocampus sections were immunostained for markers of brain endothelial cells (claudin-5, occluding, and glucose transporter-1) and astroglia (GFAP). Staining pattern and intensity were visualized by confocal microscopy and evaluated by several types of image analysis. The ultrastructure of brain capillaries was investigated by electron microscopy. Morphological changes and intensity alterations in brain endothelial tight junction proteins claudin-5 and occludin were induced by stress. Following restraint stress significant increases in the fluorescence intensity of glucose transporter-1 were detected in brain endothelial cells in the frontal cortex and hippocampus. Significant reductions in GFAP fluorescence intensity were observed in the frontal cortex in all stress groups. As observed by electron microscopy, 1-day acute stress induced morphological changes indicating damage in capillary endothelial cells in both brain regions. After 21 days of stress thicker and irregular capillary basal membranes in the hippocampus and edema in astrocytes in both regions were seen. These findings indicate that stress exerts time-dependent changes in the staining pattern of tight junction proteins occludin, claudin-5, and glucose transporter-1 at the level of brain capillaries and in the ultrastructure of brain endothelial cells and astroglial endfeet, which may contribute to neurodegenerative processes, cognitive and

  2. The Stress and Vascular Catastrophes in Newborn Rats: Mechanisms Preceding and Accompanying the Brain Hemorrhages

    PubMed Central

    Semyachkina-Glushkovskaya, Oxana; Borisova, Ekaterina; Abakumov, Maxim; Gorin, Dmitry; Avramov, Latchezar; Fedosov, Ivan; Namykin, Anton; Abdurashitov, Arkady; Serov, Alexander; Pavlov, Alexey; Zinchenko, Ekaterina; Lychagov, Vlad; Navolokin, Nikita; Shirokov, Alexander; Maslyakova, Galina; Zhu, Dan; Luo, Qingming; Chekhonin, Vladimir; Tuchin, Valery; Kurths, Jürgen

    2016-01-01

    In this study, we analyzed the time-depended scenario of stress response cascade preceding and accompanying brain hemorrhages in newborn rats using an interdisciplinary approach based on: a morphological analysis of brain tissues, coherent-domain optical technologies for visualization of the cerebral blood flow, monitoring of the cerebral oxygenation and the deformability of red blood cells (RBCs). Using a model of stress-induced brain hemorrhages (sound stress, 120 dB, 370 Hz), we studied changes in neonatal brain 2, 4, 6, 8 h after stress (the pre-hemorrhage, latent period) and 24 h after stress (the post-hemorrhage period). We found that latent period of brain hemorrhages is accompanied by gradual pathological changes in systemic, metabolic, and cellular levels of stress. The incidence of brain hemorrhages is characterized by a progression of these changes and the irreversible cell death in the brain areas involved in higher mental functions. These processes are realized via a time-depended reduction of cerebral venous blood flow and oxygenation that was accompanied by an increase in RBCs deformability. The significant depletion of the molecular layer of the prefrontal cortex and the pyramidal neurons, which are crucial for associative learning and attention, is developed as a consequence of homeostasis imbalance. Thus, stress-induced processes preceding and accompanying brain hemorrhages in neonatal period contribute to serious injuries of the brain blood circulation, cerebral metabolic activity and structural elements of cognitive function. These results are an informative platform for further studies of mechanisms underlying stress-induced brain hemorrhages during the first days of life that will improve the future generation's health. PMID:27378933

  3. The Stress and Vascular Catastrophes in Newborn Rats: Mechanisms Preceding and Accompanying the Brain Hemorrhages.

    PubMed

    Semyachkina-Glushkovskaya, Oxana; Borisova, Ekaterina; Abakumov, Maxim; Gorin, Dmitry; Avramov, Latchezar; Fedosov, Ivan; Namykin, Anton; Abdurashitov, Arkady; Serov, Alexander; Pavlov, Alexey; Zinchenko, Ekaterina; Lychagov, Vlad; Navolokin, Nikita; Shirokov, Alexander; Maslyakova, Galina; Zhu, Dan; Luo, Qingming; Chekhonin, Vladimir; Tuchin, Valery; Kurths, Jürgen

    2016-01-01

    In this study, we analyzed the time-depended scenario of stress response cascade preceding and accompanying brain hemorrhages in newborn rats using an interdisciplinary approach based on: a morphological analysis of brain tissues, coherent-domain optical technologies for visualization of the cerebral blood flow, monitoring of the cerebral oxygenation and the deformability of red blood cells (RBCs). Using a model of stress-induced brain hemorrhages (sound stress, 120 dB, 370 Hz), we studied changes in neonatal brain 2, 4, 6, 8 h after stress (the pre-hemorrhage, latent period) and 24 h after stress (the post-hemorrhage period). We found that latent period of brain hemorrhages is accompanied by gradual pathological changes in systemic, metabolic, and cellular levels of stress. The incidence of brain hemorrhages is characterized by a progression of these changes and the irreversible cell death in the brain areas involved in higher mental functions. These processes are realized via a time-depended reduction of cerebral venous blood flow and oxygenation that was accompanied by an increase in RBCs deformability. The significant depletion of the molecular layer of the prefrontal cortex and the pyramidal neurons, which are crucial for associative learning and attention, is developed as a consequence of homeostasis imbalance. Thus, stress-induced processes preceding and accompanying brain hemorrhages in neonatal period contribute to serious injuries of the brain blood circulation, cerebral metabolic activity and structural elements of cognitive function. These results are an informative platform for further studies of mechanisms underlying stress-induced brain hemorrhages during the first days of life that will improve the future generation's health. PMID:27378933

  4. Insulin-like growth factor-II (IGF II) receptor from rat brain is of lower apparent molecular weight than the IGF II receptor from rat liver

    SciTech Connect

    McElduff, A.; Poronnik, P.; Baxter, R.C.

    1987-10-01

    The binding subunits of the insulin and insulin-like growth factor-I (IGF I) receptors from rat brain are of lower molecular weight than the corresponding receptor in rat liver, possibly due to variations in sialic acid content. We have compared the IGF II receptor from rat brain and rat liver. The brain receptor is of smaller apparent mol wt (about 10 K) on sodium dodecyl sulfate polyacrylamide gel electrophoresis. This size difference is independent of ligand binding as it persists in iodinated and specifically immunoprecipitated receptors. From studies of wheat germ agglutinin binding and the effect of neuraminidase on receptor mobility, we conclude that this difference is not simply due to variations in sialic acid content. Treatment with endoglycosidase F results in reduction in the molecular size of both liver and brain receptors and after this treatment the aglycoreceptors are of similar size. We conclude that in rat brain tissue the IGF II receptor like the binding subunits of the insulin and IGF I receptors is of lower molecular size than the corresponding receptors in rat liver. This difference is due to differences in N-linked glycosylation.

  5. Protein synthesis rates in rat brain regions and subcellular fractions during aging

    SciTech Connect

    Avola, R.; Condorelli, D.F.; Ragusa, N.; Renis, M.; Alberghina, M.; Giuffrida Stella, A.M.; Lajtha, A.

    1988-04-01

    In vivo protein synthesis rates in various brain regions (cerebral cortex, cerebellum, hippocampus, hypothalamus, and striatum) of 4-, 12-, and 24-month-old rats were examined after injection of a flooding dose of labeled valine. The incorporation of labeled valine into proteins of mitochondrial, microsomal, and cytosolic fractions from cerebral cortex and cerebellum was also measured. At all ages examined, the incorporation rate was 0.5% per hour in cerebral cortex, cerebellum, hippocampus, and hypothalamus and 0.4% per hour in striatum. Of the subcellular fractions examined, the microsomal proteins were synthesized at the highest rate, followed by cytosolic and mitochondrial proteins. The results obtained indicate that the average synthesis rate of proteins in the various brain regions and subcellular fractions examined is fairly constant and is not significantly altered in the 4 to 24-month period of life of rats.

  6. In vivo functional photoacoustic tomography of traumatic brain injury in rats

    NASA Astrophysics Data System (ADS)

    Oh, Jung-Taek; Song, Kwang-Hyung; Li, Meng-Lin; Stoica, George; Wang, Lihong V.

    2006-02-01

    In this study, we demonstrate the potential of photoacoustic tomography for the study of traumatic brain injury (TBI) in rats in vivo. Based on spectroscopic photoacoustic tomography that can detect the absorption rates of oxy- and deoxy-hemoglobins, the blood oxygen saturation and total blood volume in TBI rat brains were visualized. Reproducible cerebral trauma was induced using a fluid percussion TBI device. The time courses of the hemodynamic response following the trauma initiation were imaged with multi-wavelength photoacoustic tomography with bandwidth-limited spatial resolution through the intact skin and skull. In the pilot set of experiments, trauma induced hematomas and blood oxygen saturation level changes were detected, a finding consistent with the known physiological responses to TBI. This new imaging method will be useful for future studies on TBI-related metabolic activities and the effects of therapeutic agents.

  7. Localization of P-glycoprotein at the nuclear envelope of rat brain cells

    SciTech Connect

    Babakhanian, Karlo; Bendayan, Moise; Bendayan, Reina . E-mail: r.bendayan@utoronto.ca

    2007-09-21

    P-Glycoprotein is a plasma membrane drug efflux protein implicated in extrusion of cytotoxic compounds out of a cell. There is now evidence that suggests expression of this transporter at several subcellular sites, including the nucleus, mitochondria, and Golgi apparatus. This study investigated the localization and expression of P-glycoprotein at the nuclear membrane of rat brain microvessel endothelial (RBE4) and microglial (MLS-9) cell lines. Immunocytochemistry at the light and electron microscope levels using P-glycoprotein monoclonals antibodies demonstrated the localization of the protein at the nuclear envelope of RBE4 and MLS-9 cells. Western blot analysis revealed a single band of 170-kDa in purified nuclear membranes prepared from isolated nuclei of RBE4 and MLS-9 cells. These findings indicate that P-glycoprotein is expressed at the nuclear envelope of rat brain cells and suggest a role in multidrug resistance at this subcellular site.

  8. Neurofibromin interacts with CRMP-2 and CRMP-4 in rat brain

    SciTech Connect

    Lin, Y.-L.; Hsueh, Y.-P.

    2008-05-02

    Neurofibromin, encoded by the neurofibromatosis type 1 (NF1) gene, regulates the Ras and cAMP pathways and plays a role in proliferation and neuronal morphogenesis. The details of the molecular mechanism of neurofibromin action in these processes are still unclear. In this study, immunoprecipitation and proteomics were used to identify novel proteins from rat brain that interact with neurofibromin. Mass spectrometry analysis showed that two proteins, the collapsin response mediator protein-2 (CRMP-2) and propionyl-CoA carboxylase alpha chain (PCCA), associated with neurofibromin. Immunoprecipitation-immunoblotting analysis confirmed the interactions between neurofibromin and CRMP-2 and CRMP-4, but not CRMP-1, in rat brain. CDK5, a kinase that regulates CRMP-2 in axonal outgrowth, was required for the interaction between neurofibromin and CRMP-2. Since both neurofibromin and CRMP proteins are involved in proliferation and axonal morphogenesis, these results suggest that the interaction with CRMPs contributes to the function of neurofibromin in tumorigenesis and neuronal morphogenesis.

  9. Nicotinic acid increases the lipid content of rat brain synaptosomes. [Ethanol effects

    SciTech Connect

    Basilio, C.; Flores, M.

    1989-02-09

    Chronic administration of nicotinic acid (NA) increase hepatic lipids and potentiates a similar effect induced by ethanol. The amethystic properties of NA promoted us to study its effects on the lipid content of brain synaptosomes of native and ethanol treated rats. Groups of 10 Sprague-Dawley female rats received i.p. either saline, ethanol (4g/kg), NA (50mg/kg), or a mixture of both compounds once a week during 3 weeks. The sleeping time (ST) of the animals receiving ethanol was recorded, brain synaptosomes of all groups were prepared and total lipids (TL) and cholesterol (Chol) content were determined. NA, ethanol and ethanol + NA markedly increased both TL and Chol of synaptosomes. Animals treated with ethanol or ethanol + NA developed tolerance. The group treated with ethanol-NA showed the highest Chol content and slept significantly less than the one treated with ethanol alone indicating that the changes induced by NA favored the appearance of tolerance.

  10. Autoradiographic localization of adenosine receptors in rat brain using (/sup 3/H)cyclohexyladenosine

    SciTech Connect

    Goodman, R.R.; Synder, S.H.

    1982-09-01

    Adenosine (A1) receptor binding sites have been localized in rat brain by an in vitro light microscopic autoradiographic method. The binding of (/sup 3/H)N6-cyclohexyladenosine to slide-mounted rat brain tissue sections has the characteristics of A1 receptors. It is saturable with high affinity and has appropriate pharmacology and stereospecificity. The highest densities of adenosine receptors occur in the molecular layer of the cerebellum, the molecular and polymorphic layers of the hippocampus and dentate gyrus, the medial geniculate body, certain thalamic nuclei, and the lateral septum. High densities also are observed in certain layers of the cerebral cortex, the piriform cortex, the caudate-putamen, the nucleus accumbens, and the granule cell layer of the cerebellum. Most white matter areas, as well as certain gray matter areas, such as the hypothalamus, have negligible receptor concentrations. These localizations suggest possible central nervous system sites of action of adenosine.

  11. Micro-positron emission tomography imaging of rat brain metabolism during expression of contextual conditioning.

    PubMed

    Luyten, Laura; Casteels, Cindy; Vansteenwegen, Debora; van Kuyck, Kris; Koole, Michel; Van Laere, Koen; Nuttin, Bart

    2012-01-01

    Using (18)F-fluorodeoxyglucose microPET imaging, we investigated the neurocircuitry of contextual anxiety versus control in awake, conditioned rats (n = 7-10 per group). In addition, we imaged a group expressing cued fear. Simultaneous measurements of startle amplitude and freezing time were used to assess conditioning. To the best of our knowledge, no neuroimaging studies in conditioned rats have been conducted thus far, although visualizing and quantifying the metabolism of the intact brain in behaving animals is clearly of interest. In addition, more insight into the neurocircuitry involved in contextual anxiety may stimulate the development of new treatments for anxiety disorders. Our main finding was hypermetabolism in a cluster comprising the bed nucleus of the stria terminalis (BST) in rats expressing contextual anxiety compared with controls. Analysis of a subset of rats showing the best behavioral results (n = 5 per subgroup) confirmed this finding. We also observed hypermetabolism in the same cluster in rats expressing contextual anxiety compared with rats expressing cued fear. Our results provide novel evidence for a role of the BST in the expression of contextual anxiety. PMID:22219287

  12. Changes in Rat Brain Tissue Microstructure and Stiffness during the Development of Experimental Obstructive Hydrocephalus.

    PubMed

    Jugé, Lauriane; Pong, Alice C; Bongers, Andre; Sinkus, Ralph; Bilston, Lynne E; Cheng, Shaokoon

    2016-01-01

    Understanding neural injury in hydrocephalus and how the brain changes during the course of the disease in-vivo remain unclear. This study describes brain deformation, microstructural and mechanical properties changes during obstructive hydrocephalus development in a rat model using multimodal magnetic resonance (MR) imaging. Hydrocephalus was induced in eight Sprague-Dawley rats (4 weeks old) by injecting a kaolin suspension into the cisterna magna. Six sham-injected rats were used as controls. MR imaging (9.4T, Bruker) was performed 1 day before, and at 3, 7 and 16 days post injection. T2-weighted MR images were collected to quantify brain deformation. MR elastography was used to measure brain stiffness, and diffusion tensor imaging (DTI) was conducted to observe brain tissue microstructure. Results showed that the enlargement of the ventricular system was associated with a decrease in the cortical gray matter thickness and caudate-putamen cross-sectional area (P < 0.001, for both), an alteration of the corpus callosum and periventricular white matter microstructure (CC+PVWM) and rearrangement of the cortical gray matter microstructure (P < 0.001, for both), while compression without gross microstructural alteration was evident in the caudate-putamen and ventral internal capsule (P < 0.001, for both). During hydrocephalus development, increased space between the white matter tracts was observed in the CC+PVWM (P < 0.001), while a decrease in space was observed for the ventral internal capsule (P < 0.001). For the cortical gray matter, an increase in extracellular tissue water was significantly associated with a decrease in tissue stiffness (P = 0.001). To conclude, this study characterizes the temporal changes in tissue microstructure, water content and stiffness in different brain regions and their association with ventricular enlargement. In summary, whilst diffusion changes were larger and statistically significant for majority of the brain regions studied

  13. Changes in Rat Brain Tissue Microstructure and Stiffness during the Development of Experimental Obstructive Hydrocephalus

    PubMed Central

    Jugé, Lauriane; Pong, Alice C.; Bongers, Andre; Sinkus, Ralph; Bilston, Lynne E.; Cheng, Shaokoon

    2016-01-01

    Understanding neural injury in hydrocephalus and how the brain changes during the course of the disease in-vivo remain unclear. This study describes brain deformation, microstructural and mechanical properties changes during obstructive hydrocephalus development in a rat model using multimodal magnetic resonance (MR) imaging. Hydrocephalus was induced in eight Sprague-Dawley rats (4 weeks old) by injecting a kaolin suspension into the cisterna magna. Six sham-injected rats were used as controls. MR imaging (9.4T, Bruker) was performed 1 day before, and at 3, 7 and 16 days post injection. T2-weighted MR images were collected to quantify brain deformation. MR elastography was used to measure brain stiffness, and diffusion tensor imaging (DTI) was conducted to observe brain tissue microstructure. Results showed that the enlargement of the ventricular system was associated with a decrease in the cortical gray matter thickness and caudate-putamen cross-sectional area (P < 0.001, for both), an alteration of the corpus callosum and periventricular white matter microstructure (CC+PVWM) and rearrangement of the cortical gray matter microstructure (P < 0.001, for both), while compression without gross microstructural alteration was evident in the caudate-putamen and ventral internal capsule (P < 0.001, for both). During hydrocephalus development, increased space between the white matter tracts was observed in the CC+PVWM (P < 0.001), while a decrease in space was observed for the ventral internal capsule (P < 0.001). For the cortical gray matter, an increase in extracellular tissue water was significantly associated with a decrease in tissue stiffness (P = 0.001). To conclude, this study characterizes the temporal changes in tissue microstructure, water content and stiffness in different brain regions and their association with ventricular enlargement. In summary, whilst diffusion changes were larger and statistically significant for majority of the brain regions studied

  14. Postmortem changes in rat brain: studies on membrane-bound enzymes and receptors.

    PubMed

    Syapin, P J; Ritchie, T; Noble, L; Noble, E P

    1987-04-01

    The relationship between the stability of potential neurochemical markers and autolysis time was studied at 4 degrees C and 25 degrees C using postmortem brain samples from two rat strains. In general, qualitatively similar results were obtained with either N/Nih or Sprague-Dawley rats; however, quantitative differences were often observed, particularly in regard to benzodiazepine receptor changes. For every enzyme activity or binding property examined, no significant change was found when brains were kept at 4 degrees C for up to 72 h prior to freezing at -70 degrees C. Na,K-ATPase and low-affinity Ca-ATPase activities were also stable in brains kept at 25 degrees C for up to 72 h. Mg-ATPase activity was reduced in brains kept at 25 degrees C for 24 and 48 h. [3H]Guanidinoethylmercaptosuccinic acid [( 3H]GEMSA) binding to enkephalin convertase in the cytosol was not significantly changed in brains kept at 25 degrees C; however, a small increase was seen for [3H]GEMSA binding to the membrane fraction at 24, but not 48 and 72 h postmortem. [3H]Quinuclidinyl benzilate [( 3H]QNB) binding to muscarinic cholinergic receptors decreased in brains kept at 25 degrees C for 72 h. Opioid receptor binding also decreased in brains kept at 25 degrees C. Using [3H]2-D-alanine-5-D-leucine enkephalin to label delta opioid receptors, a statistically significant decrease in binding was observed as early as 6 h postmortem, and was completely abolished after 72 h at 25 degrees C. In contrast, [3H]naloxone binding was unchanged after 24 h at 25 degrees C, but was decreased after 48 and 72 h.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3029332

  15. Repeated BOLD-fMRI imaging of deep brain stimulation responses in rats.

    PubMed

    Chao, Tzu-Hao Harry; Chen, Jyh-Horng; Yen, Chen-Tung

    2014-01-01

    Functional magnetic resonance imaging (fMRI) provides a picture of the global spatial activation pattern of the brain. Interest is growing regarding the application of fMRI to rodent models to investigate adult brain plasticity. To date, most rodent studies used an electrical forepaw stimulation model to acquire fMRI data, with α-chloralose as the anesthetic. However, α-chloralose is harmful to animals, and not suitable for longitudinal studies. Moreover, peripheral stimulation models enable only a limited number of brain regions to be studied. Processing between peripheral regions and the brain is multisynaptic, and renders interpretation difficult and uncertain. In the present study, we combined the medetomidine-based fMRI protocol (a noninvasive rodent fMRI protocol) with chronic implantation of an MRI-compatible stimulation electrode in the ventroposterior (VP) thalamus to repetitively sample thalamocortical responses in the rat brain. Using this model, we scanned the forebrain responses evoked by the VP stimulation repeatedly of individual rats over 1 week. Cortical BOLD responses were compared between the 2 profiles obtained at day1 and day8. We discovered reproducible frequency- and amplitude-dependent BOLD responses in the ipsilateral somatosensory cortex (S1). The S1 BOLD responses during the 2 sessions were conserved in maximal response amplitude, area size (size ratio from 0.88 to 0.91), and location (overlap ratio from 0.61 to 0.67). The present study provides a long-term chronic brain stimulation protocol for studying the plasticity of specific neural circuits in the rodent brain by BOLD-fMRI. PMID:24825464

  16. Quantitative Mapping of Trimethyltin Injury in the Rat Brain Using Magnetic Resonance Histology

    PubMed Central

    Johnson, G. Allan; Calabrese, Evan; Little, Peter B.; Hedlund, Laurence; Qi, Yi; Badea, Alexandra

    2014-01-01

    The growing exposure to chemicals in our environment and the increasing concern over their impact on health have elevated the need for new methods for surveying the detrimental effects of these compounds. Today’s gold standard for assessing the effects of toxicants on the brain is based on hematoxylin and eosin (H&E)-stained histology, sometimes accompanied by special stains or immunohistochemistry for neural processes and myelin. This approach is time-consuming and is usually limited to a fraction of the total brain volume. We demonstrate that magnetic resonance histology (MRH) can be used for quantitatively assessing the effects of central nervous system toxicants in rat models. We show that subtle and sparse changes to brain structure can be detected using magnetic resonance histology, and correspond to some of the locations in which lesions are found by traditional pathological examination. We report for the first time diffusion tensor image-based detection of changes in white matter regions, including fimbria and corpus callosum, in the brains of rats exposed to 8 mg/Kg and 12 mg/Kg trimethyltin. Besides detecting brain-wide changes, magnetic resonance histology provides a quantitative assessment of dose-dependent effects. These effects can be found in different magnetic resonance contrast mechanisms, providing multivariate biomarkers for the same spatial location. In this study, deformation-based morphometry detected areas where previous studies have detected cell loss, while voxel-wise analyses of diffusion tensor parameters revealed microstructural changes due to such things as cellular swelling, apoptosis, and inflammation. Magnetic resonance histology brings a valuable addition to pathology with the ability to generate brain-wide quantitative parametric maps for markers of toxic insults in the rodent brain. PMID:24631313

  17. Repeated BOLD-fMRI Imaging of Deep Brain Stimulation Responses in Rats

    PubMed Central

    Chao, Tzu-Hao Harry; Chen, Jyh-Horng; Yen, Chen-Tung

    2014-01-01

    Functional magnetic resonance imaging (fMRI) provides a picture of the global spatial activation pattern of the brain. Interest is growing regarding the application of fMRI to rodent models to investigate adult brain plasticity. To date, most rodent studies used an electrical forepaw stimulation model to acquire fMRI data, with α-chloralose as the anesthetic. However, α-chloralose is harmful to animals, and not suitable for longitudinal studies. Moreover, peripheral stimulation models enable only a limited number of brain regions to be studied. Processing between peripheral regions and the brain is multisynaptic, and renders interpretation difficult and uncertain. In the present study, we combined the medetomidine-based fMRI protocol (a noninvasive rodent fMRI protocol) with chronic implantation of an MRI-compatible stimulation electrode in the ventroposterior (VP) thalamus to repetitively sample thalamocortical responses in the rat brain. Using this model, we scanned the forebrain responses evoked by the VP stimulation repeatedly of individual rats over 1 week. Cortical BOLD responses were compared between the 2 profiles obtained at day1 and day8. We discovered reproducible frequency- and amplitude-dependent BOLD responses in the ipsilateral somatosensory cortex (S1). The S1 BOLD responses during the 2 sessions were conserved in maximal response amplitude, area size (size ratio from 0.88 to 0.91), and location (overlap ratio from 0.61 to 0.67). The present study provides a long-term chronic brain stimulation protocol for studying the plasticity of specific neural circuits in the rodent brain by BOLD-fMRI. PMID:24825464

  18. Neuroglobin expression and oxidant/antioxidant balance after graded traumatic brain injury in the rat.

    PubMed

    Di Pietro, Valentina; Lazzarino, Giacomo; Amorini, Angela Maria; Tavazzi, Barbara; D'Urso, Serafina; Longo, Salvatore; Vagnozzi, Roberto; Signoretti, Stefano; Clementi, Elisabetta; Giardina, Bruno; Lazzarino, Giuseppe; Belli, Antonio

    2014-04-01

    Neuroglobin is a neuron-specific hexacoordinated globin capable of binding various ligands, including O2, NO, and CO, the biological function of which is still uncertain. Various studies seem to indicate that neuroglobin is a neuroprotective agent when overexpressed, acting as a potent inhibitor of oxidative and nitrosative stress. In this study, we evaluated the pathophysiological response of the neuroglobin gene and protein expression in the cerebral tissue of rats sustaining traumatic brain injury of differing severity, while simultaneously measuring the oxidant/antioxidant balance. Two levels of trauma (mild and severe) were induced in anesthetized animals using the weight-drop model of diffuse axonal injury. Rats were then sacrificed at 6, 12, 24, 48, and 120 h after traumatic brain injury, and the gene and protein expression of neuroglobin and the concentrations of malondialdehyde (as a parameter representative of reactive oxygen species-mediated damage), nitrite + nitrate (indicative of NO metabolism), ascorbate, and glutathione (GSH) were determined in the brain tissue. Results indicated that mild traumatic brain injury, although causing a reversible increase in oxidative/nitrosative stress (increase in malondialdehyde and nitrite + nitrate) and an imbalance in antioxidants (decrease in ascorbate and GSH), did not induce any change in neuroglobin. Conversely, severe traumatic brain injury caused an over nine- and a fivefold increase in neuroglobin gene and protein expression, respectively, as well as a remarkable increase in oxidative/nitrosative stress and depletion of antioxidants. The results of this study, showing a lack of effect in mild traumatic brain injury as well as asynchronous time course changes in neuroglobin expression, oxidative/nitrosative stress, and antioxidants in severe traumatic brain injury, do not seem to support the role of neuroglobin as an endogenous neuroprotective antioxidant agent, at least under pathophysiological conditions

  19. Regional distribution and postnatal changes of D-amino acids in rat brain.

    PubMed

    Hamase, K; Homma, H; Takigawa, Y; Fukushima, T; Santa, T; Imai, K

    1997-03-15

    Regional distribution of D-amino acids in rat brain was studied by the modified highly sensitive analytical method which was previously developed. The method includes fluorogenic derivatization of each amino acid, isolation of each amino acid by reverse-phase HPLC, followed by enantiomeric separation with Pirkle-type chiral stationary phases. D-Amino acid contents were determined in the cerebrum, cerebellum, hippocampus, medulla oblongata, pituitary gland and pineal gland. D-Aspartic acid was observed in the pineal gland (3524 +/- 263 nmol/g, data are for male rats of 6 weeks of age) and the pituitary gland (80.5 +/- 9.0 nmol/g). D-Serine was found in various regions of the brain except for the cerebellum and medulla oblongata. D-Alanine was observed exclusively in the pituitary gland (25.9 +/- 4.4 nmol/g), whereas D-leucine was found in the pineal gland (3.4 +/- 0.4 nmol/g) and the hippocampus (1.6 +/- 0.07 nmol/g). No other D-amino acids were detected in the brain. The contents of D-aspartic acid in the pituitary gland and D-serine in the pineal gland were higher in female rats. In contrast the contents of D-alanine in the pituitary gland and D-leucine in the pineal gland and the hippocampus were higher in males. Postnatal changes of D-aspartic acid and D-leucine in the pineal gland and D-alanine in the pituitary gland were also investigated. The results described in this paper suggested that distinct regulatory mechanisms exist for individual D-amino acids in the corresponding region of rat brain. PMID:9101716

  20. DNA microarray unravels rapid changes in transcriptome of MK-801 treated rat brain

    PubMed Central

    Kobayashi, Yuka; Kulikova, Sofya P; Shibato, Junko; Rakwal, Randeep; Satoh, Hiroyuki; Pinault, Didier; Masuo, Yoshinori

    2015-01-01

    AIM: To investigate the impact of MK-801 on gene expression patterns genome wide in rat brain regions. METHODS: Rats were treated with an intraperitoneal injection of MK-801 [0.08 (low-dose) and 0.16 (high-dose) mg/kg] or NaCl (vehicle control). In a first series of experiment, the frontoparietal electrocorticogram was recorded 15 min before and 60 min after injection. In a second series of experiments, the whole brain of each animal was rapidly removed at 40 min post-injection, and different regions were separated: amygdala, cerebral cortex, hippocampus, hypothalamus, midbrain and ventral striatum on ice followed by DNA microarray (4 × 44 K whole rat genome chip) analysis. RESULTS: Spectral analysis revealed that a