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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
231

Prenatální expozice metamfetamínu a její vliv na genovou expresi ve vybraných částech mozku pokusného potkana / Prenatal exposure to methamphetamine and its effect on the gene expression in the selected parts of the brains of experimental rats

Tomášková, Anežka January 2017 (has links)
Introduction: Methamphetamine is a drug frequently abused by drug-addicted pregnant women and also one of the mostcommonly used drugs in the CzechRepublic. This drug passes easily through a placental barrier into the fetus. Thus it can negatively affect not only the mother but also the prenatal development of her offspring. Objectives: In the framework of the grant project GA CR: 14-03708S, the long-term effects of prenatal exposure to methamphetamine were detected. It was determined whether the prenatal methamphetamine exposure affects the generation of offspring of exposed females at the level of gene expression of genes in specific regions of the brain, striatum, hippocampus and prefrontal cortex. Methods: In the selected parts of the brain, which were removed from the rat, the microarray hybridization and the real-time PCR to express changes in expression of selected genes were performed. Results: Statistical analysis of microarray hybridization did not show the significantly altered gene expression in tested genes significantly. Only boundary values for 13 genes were measured, which were further tested by real-time PCR.After a statistic evaluation of real-time PCR, the significantly altered expression was found in 2 genes. The significantly changed expression of DRD3 and TACR3 genes was found...
232

Nastavení genové exprese v dospělém mozku pokusného potkana po prenatálním vystavení metamfetaminu / Gene expression pattern in the adult brain of the experimental rat after prenatal exposure to methamphetamine

Tomášková, Anežka January 2018 (has links)
Introduction: Methamphetamine is a drug frequently taken by drug-addicted pregnant women and happens to be one of the most commonly used drugs in the Czech Republic. This drug passes easily through a placental barrier into the fetus. Thus it can negatively affect not only the mother but also the prenatal development of her offspring. Objectives: This research aims to provide a general screening of gene expression in selected regions of the F1 generation of the brain prenatally affected by methamphetamine, to verify whether exposure to methamphetamine affects the generation of offspring of exposed females at the level of gene expression in selected regions of the brain, and to valuate possible changes in gene expression. Methods: In selected parts of the brain, collected from a rat, the microarray hybridization and the real-time PCR were set to evaluate express changes in the expression of selected genes. Results: Statistical analysis of the microarray hybridization did not show a significantly altered gene expression in the tested genes. Only boundary values for 13 genes were measured, which were further tested by the real-time PCR. After a statistic evaluation of the real-time PCR, the significantly altered expression was found in 2 genes. The notably changed expression of DRD3 and TACR3 genes...
233

Enhanced Oral Activity Responses to Intrastriatal SKF 38393 and M-CPP Are Attenuated by Intrastriatal Mianserin in Neonatal 6-OHDA-Lesioned Rats

Plech, A., Brus, R., Kostrzewa, R. M., Kalbfleisch, J. H. 01 June 1995 (has links)
Enhanced oral activity is induced in neonatal 6-hydroxydopamine- (6-OHDA-) lesioned rats by systemic administration of the dopamine (DA) D1 receptor agonist SKF 38393 and serotonin (5-HT) 5-HT2A,2C agonist m-chlorophenylpiperazine (m-CPP). The DA D1 receptor antagonist SCH 23390 effectively attenuates the effect of SKF 38393 but not m-CPP. The 5-HT2antagonist mianserin attenuates the effects of both m-CPP and SKF 38393, suggesting that DA agonist effects are mediated by 5-HT neurochemical systems. To test whether DA and 5-HT agonist effects and interactions might occur within the neostriatum, rats were implanted with permanent injection cannulae, with tips in the ventral striatum. One group of rats was lesioned at 3 days after birth with 6-OHDA HBr (100 μg salt form, in each lateral ventricle; desipramine HCl pretreatment, 20 mg/kg IP, base form, 1 h), while controls received the vehicle in place of 6-OHDA. Cannulae were implanted when rats weighed 200-250 g. During a 1-h observation session SKF 38393 (5 nmol per side) produced 74.3±19.2 oral movements in intact rats and 310.7±97.0 oral movements in 6-OHDA-lesioned rats. m-CPP (10 nmol per side) produced 72.6±15.1 and 274.5±65.0 oral movements in these respective groups. These responses were several-fold greater than the 25.3±7.3 and 41.8±9.5 oral movements in the same groups after saline (0.5 μl per side) (P<0.05). Mianserin (6 nmol per side) alone had no effect on oral activity but attenuated responses to both SKF 38393 and m-CPP in intact and 6-OHDA-lesioned rats. These findings demonstrate that enhanced oral activity responses are produced by intrastriatal SKF 38393 and m-CPP in neonatal 6-OHDA-lesioned rats. Also, when the 5-HT2 receptor antagonist mianserin was administered intrastriatally, induction of oral activity by the DA D1 agonist SKF 38393 was attenuated. These findings indicate that ventral striatum represents at least one brain focus at which DA and 5-HT systems interact to modulate oral activity in rats.
234

Brain Sites of Movement Disorder: Genetic and Environmental Agents in Neurodevelopmental Perturbations

Palomo, T., Beninger, R. J., Kostrzewa, R. M., Archer, Trevor 01 December 2003 (has links)
In assessing and assimilating the neurodevelopmental basis of the so-called movement disorders it is probably useful to establish certain concepts that will modulate both the variation and selection of affliction, mechanisms-processes and diversity of disease states. Both genetic, developmental and degenerative aberrations are to be encompassed within such an approach, as well as all deviations from the necessary components of behaviour that are generally understood to incorporate "normal" functioning. In the present treatise, both conditions of hyperactivity/hypoactivity, akinesia and bradykinesia together with a constellation of other symptoms and syndromes are considered in conjunction with the neuropharmacological and brain morphological alterations that may or may not accompany them, e.g. following neonatal denervation. As a case in point, the neuroanatomical and neurochemical points of interaction in Attention Deficit and Hyperactivity disorder (ADHD) are examined with reference to both the perinatal metallic and organic environment and genetic backgrounds. The role of apoptosis, as opposed to necrosis, in cell death during grain development necessitates careful considerations of the current explosion of evidence for brain nerve growth factors, neurotrophins and cytokines, and the processes regulating their appearance, release and fate. Some of these processes may posses putative inherited characteristics, like asynuclein, others may to greater or lesser extents be endogenous or semi-endogenous (in food), like the tetrahydroisoquinolines, others exogenous until inhaled or injested through environmental accident, like heavy metals, e.g. mercury. Another central concept of neurodevelopment is cellular plasticity, thereby underlining the essential involvement of glutamate systems and N-methyl-D-aspartate receptor configurations. Finally, an essential assimilation of brain development in disease must delineate the relative merits of inherited as opposed to environmental risks not only for the commonly-regarded movement disorders, like Parkinson's disease, Huntington's disease and epilepsy, but also for afflictions bearing strong elements of psychosocial tragedy, like ADHD, autism and Savantism.
235

Anatomical mapping of dopamine receptor supersensitivity in the rat extended striatum

Kaur, Navneet, 1979- January 2008 (has links)
No description available.
236

Where not what: the role of spatial-motor processing in decision-making

Banks, Parker January 2021 (has links)
Decision-making is comprised of an incredibly varied set of behaviours. However, all vertebrates tend to repeat previously rewarding actions and avoid those that have led to loss, behaviours known collectively as the win-stay, lose-shift strategy. This response strategy is supported by the sensorimotor striatum and nucleus accumbens, structures also implicated in spatial processing and the integration of sensory information in order to guide motor action. Therefore, choices may be represented as spatial-motor actions whose value is determined by the rewards and punishments associated with that action. In this dissertation I demonstrate that the location of choices relative to previous rewards and punishments, rather than their identities, determines their value. Chapters 2 and 4 demonstrate that the location of rewards and punishments drives future decisions to win-stay or lose-shift towards that location. Even when choices differ in colour or shape, choice value is determined by location, not visual identity. Chapter 3 compares decision-making when two, six, twelve, or eighteen choices are present, finding that the value of a win or loss is not tied to a single location, but is distributed throughout the choice environment. Finally, Chapter 5 provides anatomical support for the spatial-motor basis of choice. Specifically, win-stay responses are associated with greater oscillatory activity than win-shift responses in the motor cortex corresponding to the hand used to make a choice, whereas lose-shift responses are accompanied by greater activation of frontal systems compared to lose-stay responses. The win-stay and lose-shift behaviours activate structures known to project to different regions of the striatum. Overall, this dissertation provides behavioural evidence that choice location, not visual identity, determines choice value. / Thesis / Doctor of Philosophy (PhD)
237

Parvalbumin-producing striatal interneurons received excitatory inputs onto proximal dendrites from motor thalamus in male mice / 線条体パルブアルブミン発現介在ニューロンは運動視床の入力を近位樹状突起に受ける / センジョウタイ パルブアルブミン ハツゲン カイザイ ニューロン ワ ウンドウ シショウ ノ ニュウリョク オ キンイ ジュジョウ トッキ ニ ウケル

中野 泰岳, Yasutake Nakano 22 March 2018 (has links)
本研究は、線条体パルブアルブミン発現ニューロン(PVニューロン)が受け取るグルタミン酸作動性軸索投射を順行性ウィルストレーサーを用い形態学的に調べた。その結果、運動皮質および視床腹側部からのグルタミン酸作動性軸索入力はいずれもPVニューロン樹状突起の広範囲に投射を行っているものの、視床腹側部の投射のみが細胞体から20µm程度の近位樹状突起に高密度な分布を示すことが明らかとなった。 / Using bacterial artificial chromosome transgenic mice expressing somatodendritic membrane–targeted green fluorescent protein in striatal parvalbumin (PV) interneurons, we demonstrate that glutamatergic inputs originating from the ventral anterior/ventral lateral motor thalamus preferentially contact on proximal dendrites, while inputs from motor cortex are uniformly distributed on PV neurons. These results were confirmed using a combination of vesicular glutamate transporter immunoreactions. Collectively, these findings suggest that PV neurons produce fast and reliable inhibition of medium spiny neurons in response to thalamic inputs. In contrast, excitatory inputs from motor cortices modulate PV dendrite excitability, possibly in concert with other glutamatergic, GABAergic, and dopaminergic inputs. / 博士(理学) / Doctor of Philosophy in Science / 同志社大学 / Doshisha University
238

Impaired Striatal Dopamine Receptor Development: Differential D-1 Regulation in Adults

Saleh, M. I., Kostrzewa, Richard M. 23 September 1988 (has links)
Previous reports have indicated that prenatal, but not postnatal, haloperidol impairs the ontogenic development of striatal dopamine D-2 receptors. In the present study a specific D-2 receptor antagonist, spiroperidol (1.0 mg/kg i.p.) and/or a specific D-1 receptor antagonist, SCH 23390 (0.30 mg/kg i.p.), was administered to rats for 32 successive days from birth. Postnatal spiroperidol and SCH 23390 treaments markedly impaired the development of striatal dopamine D-2 and D-1 receptors, respectively, at 12 weeks after birth. Spiroperidol did not affect D-1 receptor development and did not modify the effect of SCH 23390 treatment. Also, SCH 23390 did not affect D-2 receptor development and did not modify the effect of spiroperidol treatment. When rats with impaired development of striatal D-2 receptors were challenged at 12 weeks with spiroperidol (1.0 mg/kg per day i.p. × 17 days) D-2 receptors did not up-regulate. However, when rats with impaired development of striatal D-1 receptors were challenged at 12 weeks with SCH 23390 (0.30 mg/kg per day i.p. × 17 days) D-1 receptors did up-regulate. These findings demonstrate that postnatal treatment with D-1 and D-2 receptor antagonists can permanently impair the development of striatal D-1 and D-2 receptors. Moreover, the ability of developmentally impaired striatal D-1 receptors to up-regulate in adulthood appears to be greater than that for the developmentally impaired striatal D-2 receptors.
239

Neuroprotection in a rotenone model of Parkinson's disease

Carriere, Candace 11 1900 (has links)
The pesticide/neurotoxin, rotenone, has been shown to cause systemic inhibition of mitochondrial complex I activity, with consequent degeneration of the nigrostriatal pathway, as observed in Parkinson’s disease. A novel intrastriatal rotenone model of Parkinson’s disease was used to examine the neuroprotective effects of valproic acid (VPA) and melatonin, both of which are known to induce neurotrophic gene expression in the central nervous system via mechanisms which may involve epigenetic modulation. In these studies, sham or lesioned rats were treated with either vehicle, VPA (4mg/mL), or melatonin (4µg/mL) in drinking water. Results from a forelimb asymmetry test indicated a significant decrease in use of the contralateral forelimb in rotenone-infused animals, in the third week post-surgery, which was abolished by VPA treatment. Apomorphine administration resulted in significantly higher ipsilateral rotation in rotenone-lesioned (12µg) animals, as compared to controls, which was attenuated by melatonin treatment. Subsequent immunohistochemical examination revealed a decrease in tyrosine hydroxylase immunoreactivity within the striatum and substantia nigra of rotenone-infused animals. VPA or melatonin treatment prevented this decrease in tyrosine hydroxylase in the striatum and substantia nigra. Stereological cell counting indicated a significant decrease in dopamine neurons within the substantia nigra of rotenone-treated animals. Importantly, this loss of dopamine neurons in rotenone-infused animals was blocked by chronic VPA or melatonin treatment. A third study explored whether rotenone infusion into the medial forebrain bundle and substantia nigra in mice could provide a model of Parkinson's disease. Densitometric analysis revealed a significant depletion of tyrosine hydroxylase immunofluorescence within the ipsilateral striatum and substantia nigra of lesioned animals, and a significant bilateral overexpression of α-synuclein in the substantia nigra, as compared to control animals. These novel findings support the use of intracranial rotenone as a Parkinsonian model, and provide a solid platform for future combinatorial therapeutic approaches with VPA and melatonin. / Dissertation / Doctor of Philosophy (PhD)
240

Implication du récepteur nucléaire orphelin Nur77 (Nr4a1) dans les effets des antipsychotiques par une approche de transcriptomique chez des rats déficients en Nur77

Majeur, Simon 11 1900 (has links)
Malgré l’usage de médicaments antipsychotiques depuis plusieurs décennies, leur mécanisme d’action précis, autre que leur interaction avec les récepteurs dopaminergiques et sérotoninergiques, demeure peu connu. Nur77 (Nr4a1 ou NGFI-B) est un facteur de transcription de la famille des récepteurs nucléaires associé aux effets des antipsychotiques. Ceci étant dit, le mécanisme d’action de Nur77 est également peu connu. Afin de mieux comprendre les éléments impliqués avec les antipsychotiques et l’activité de Nur77, nous avons comparé les niveaux de transcrits dans le striatum suite à un traitement avec l’halopéridol chez des rats sauvages et déficients en Nur77 à l’aide de la technique de séquençage à haut débit (RNAseq) et d’une analyse bio-informatique. L’halopéridol et Nur77 ont modulé d’importants groupes de gènes associés avec la signalisation des récepteurs dopaminergiques et la synapse glutamatergique. L’analyse a révélé des modulations de gènes clés reliés à la signalisation des protéines G. Parmi les transcrits modulés significativement chez les rats traités avec halopéridol et ceux déficients en Nur77, la dual specificity phosphatase 5 (Dusp5) représente un nouveau candidat d’intérêt. En effet, nous avons confirmé que les niveaux d’ARNm et protéiques de Dusp5 dans le striatum sont associés aux mouvements involontaires anormaux (dyskinésie) dans un modèle de primates non-humains traités chroniquement avec halopéridol. Cette analyse transcriptomique a démontré des altérations rapides et importantes d’éléments impliqués dans la signalisation des protéines G par l’halopéridol, et a permis d’identifier, pour la première fois, une expression de Dusp5 dépendante de Nur77 en tant que nouvelle composante reliée avec la dyskinésie tardive. / Despite antipsychotic drugs being used for several decades, their precise mechanism of action remains elusive. Nur77 (Nr4a1 or NGFI-B) is a transcription factor of the nuclear receptor family associated with antipsychotic drug effects. However, the mechanism of action of Nur77 is also not well understood. To better understand the signaling components implicated with antipsychotic drug use and Nur77 activity, we compared striatal gene transcripts following haloperidol in wild-type and Nur77-deficient rats using Next Generation RNA Sequencing (RNAseq) and a bioinformatics analysis. Haloperidol and Nur77 modulated important subsets of striatal genes associated with dopamine receptor signaling and glutamate synapses. The analysis revealed modulations of key components of G protein signaling that are consistent with a rapid adaptation of striatal cells that may partially explain long-term haloperidol-induced dopamine D2 receptor upregulation. Amongst significantly modulated transcripts in rats treated with haloperidol and rats deficient in Nur77, dual specificity phosphatase 5 (Dusp5) represents a new and very interesting candidate. Indeed, we confirmed that striatal Dusp5 mRNA and protein levels were associated with abnormal involuntary movements (dyskinesia) in non-human primates chronically exposed to haloperidol. This transcriptomic analysis showed important haloperidol-induced G protein-coupled receptor signaling alterations that may support a regulatory role of Nur77 in dopamine D2 receptor signaling pathways and identified, for the first time, a putative Nur77-dependent expression of Dusp5 as a new signaling component for antipsychotic drug-induced tardive dyskinesia.

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