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21	5HT 2 Rezeptor vermittelte Kontrolle des neonatalen medullären respiratorischen Netzwerks des Säugers / 5HT 2 receptor mediated control of the medullary respiratory center in neonatal mammals Günther, Silke Kerstin Karin 25 April 2002 (has links) No description available. 570 Biowissenschaften, Biologie Mathematics and Computer Science Serotonin Rezeptoren Prä-Bötzinger Komplex medulläres respiratorisches Zentrum serotonin receptors Pre-Bötzinger Complex brainstem respiratory network 42.17 42.63 WI WK
22	Adult brain plasticity Klempin, Friederike Claudia 13 November 2008 (has links) Der Hippocampus ist eine von zwei Gehirnregionen, in der zeitlebens kontinuierlich neue Nervenzellen gebildet werden. Er spielt eine wichtige Rolle bei der Gedächtniskonsolidierung und wird mit der funktionellen Entstehung neurodegenerativer Erkrankungen in Verbindung gebracht. Strukturveränderungen im erwachsenen Gehirn, die mit einer Depression einhergehen, sind laut Literatur auf einen geringen Serotoninspiegel und reduzierte hippocampale Neurogenese zurückzuführen. Selektive Serotonin-Wiederaufnahmehemmer (SSRI) erhöhen die Serotoninkonzentration im synaptischen Spalt und üben einen positiven Effekt auf die adulte Neurogenese aus. In der vorliegenden Arbeit wird untersucht, wie Veränderungen in der Serotonin (5-HT)-Neurotransmission durch einmalige oder chronische Gaben von Fluoxetin und speziellen Agonisten und Antagonisten für die Serotoninrezeptoren 5-HT1a und 5-HT2 in der erwachsenen Maus die Proliferation und Differenzierung von neugebildeten Nervenzellen im Gyrus dentatus beeinflussen. Die Ergebnisse zeigen, dass ein konträres Agieren beider Rezeptoren zu einem ausgewogenen Serotoninspiegel führt. 5-HT1a- und 5-HT2c-Rezeptoren haben einen Einfluss auf das Überleben neugebildeter Nervenzellen, wobei sie unterschiedliche Entwicklungsstadien innerhalb der adulten Neurogenese kontrollieren. Die vorliegende Arbeit bekräftigt außerdem, dass die chronische Gabe von Fluoxetin die adulte Neurogenese steigert. / The hippocampus as one region with ongoing neurogenesis throughout life contributes to the formation of long-term memory and has also been implicated in the pathology of major depression. Studies suggest that depression might be due to decreased levels of serotonin and reduced neurogenesis in the adult brain and that the beneficial effects of selective serotonin reuptake inhibitors would require adult hippocampal neurogenesis. Here, I investigated how modulation of serotonergic neurotransmission by acute and chronic treatment with the antidepressant fluoxetine, and selective serotonin receptor agonists and antagonists in adult mice influences precursor cell activity during development. I focused on 5-HT1a and 5-HT2 receptors as major mediators of serotonin action. The present findings suggest that an opposed action of 5-HT1a and 5-HT2c receptor subtypes result in a balanced regulation of serotonin levels in the dentate gyrus. Both receptors differentially affect intermediate cell stages in adult hippocampal neurogenesis and play an important role in the survival of newly generated neurons. Furthermore, this study confirms that chronic fluoxetine treatment increases adult neurogenesis. In conclusion, the latency of onset of fluoxetine action can be explained by a balanced interplay of 5-HT1a and 5-HT2c receptor subtypes. Adulte Neurogenese Gyrus dentatus Serotoninrezeptoren Hippocampus Fluoxetin dentate gyrus hippocampus Adult neurogenesis serotonin receptors fluoxetine 570 Biowissenschaften, Biologie 32 Biologie WW 2400 ddc:570
23	Roles of serotonin 2A receptor in a serotonin syndrome Unknown Date (has links) Serotonin (5-HT) is a neurotransmitter in the central nervous system. Decrease in the brain 5-HT level could induce depression, showing a state of low mood, aversion to motion and feeling of worthlessness. About 12 million adults in the United States have depression. Antidepressants, such as monoamine oxidase inhibitors and selective serotonin reuptake inhibitors, can alleviate the depressive mood by increasing the brain's 5-HT activity, however they can also induce a potentially life-threatening side effect, namely 5-HT syndrome. This syndrome is manifested by neuromuscular hyperactivities, mental disorders and autonomic dysfunctions. Clinical studies have demonstrated that 5-HT2A receptor antagonists could effectively block severe symptoms of patients with the 5-HT syndrome. To understand the underlying mechanisms, in this study we examined the activity of the 5-HT2A receptor in rats with the 5-HT syndrome evoked by a combined injection of clorgyline, a monoamine oxidase inhibitor , and paroxetine, a selective 5-HT reuptake inhibitor. The major findings from my study were that: (1) Chronic clorgyline treatment significantly exacerbated 5-HT2A receptor-mediated symptoms of the 5-HT syndrome animals; (2) The 5-HT2A receptor-mediated symptoms were also aggravated when the 5-HT syndrome animals were housed in warm (32 ÀC) ambient temperature; (3) Blocking 5-HT2A receptors in the medial prefrontal cortex alleviated the 5-HT syndrome through a circuit between raphe serotonergic neurons and medial prefrontal cortex glutamatergic neurons. Taken together, my data demonstrate that the activity of 5-HT2A receptors may be enhanced by chronic antidepressant treatment and warm environmental temperature. / The sensitized 5-HT2A receptor in the medial prefrontal cortex may exacerbate the syndrome through a positive-feedback circuit between medial prefrontal cortex and raphe nuclei, which would result in excessive 5-HT in the brain. This study casts a new light on the underlying mechanisms of the 5-HT syndrome. / by Gongliang Zhang. / Thesis (Ph.D.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web. Central nervous system--Physiology Neurotransmitter receptors Serotoninergic mechanisms
24	ASSESSMENT OF BOVINE VASCULAR SEROTONIN RECEPTOR POPULATIONS AND TRANSPORT OF ERGOT ALKALOIDS IN THE SMALL INTESTINE Snider, Miriam A. 01 January 2017 (has links) Prior work using a contractility bioassay determined that the serotonin (5-HT) receptor subtype 5-HT2A is present in bovine lateral saphenous veins and plays a role in ergot alkaloid-induced vascular contraction in steers grazing endophyte-infected (Epichloë coenophiala) tall fescue (Lolium arundinaceum). A study was conducted to determine what 5-HT receptors are involved in vasoconstriction of bovine gut vasculature. The findings of this study indicate that 5-HT2A is present and may play a role in ergot alkaloid induced vasoconstriction. A second study was conducted to determine if ergot alkaloids were transported in the small intestine. The active transporter, peptide transporter 1 (PepT1), was evaluated for its role in the transport of various concentrations of ergot alkaloids across Caco-2 cell monolayers. Results indicate that CEPH, ERT, EXT, and LSA do move across Caco-2 cell monolayers, but appear to utilize PepT1 at larger concentrations. Overall, the demonstrated presence of 5-HT2A receptors in the bovine gut vasculature established a potential for vascular interference by ergot alkaloids entering the bloodstream through transepithelial absorption. fescue toxicosis serotonin receptors mesenteric and ruminal vasculature Caco-2 cells ergot alkaloid transport peptide transporter 1 Animal Sciences Cellular and Molecular Physiology Nutrition
25	Homology modeling and structural analysis of the antipsychotic drugs receptorome López Muñoz, Laura 22 June 2010 (has links) Classically it was assumed that the compounds with therapeutic effect exert their action interacting with a single receptor. Nowadays it is widely recognized that the pharmacological effect of most drugs is more complex and involves a set of receptors, some associated to their positive effects and some others to the side effects and toxicity. Antipsychotic drugs are an example of effective compounds characterized by a complex pharmacological profile binding to several receptors (mainly G protein-coupled-receptors, GPCR). In this work we will present a detailed study of known antipsychotic drugs and the receptors potentially involved in their binding profile, in order to understand the molecular mechanisms of the antipsychotic pharmacologic effects.The study started with obtaining homology models for all the receptors putatively involved in the antipsychotic drugs receptorome, suitable for building consistent drug-receptor complexes. These complexes were structurally analyzed and compared using multivariate statistical methods, which in turn allowed the identification of the relationship between the pharmacological properties of the antipsychotic drugs and the structural differences in the receptor targets. The results can be exploited for the design of safer and more effective antipsychotic drugs with an optimum binding profile. / Tradicionalmente se asumía que los fármacos terapéuticamente efectivos actuaban interaccionando con un único receptor. Actualmente está ampliamente reconocido que el efecto farmacológico de la mayoría de los fármacos es más complejo y abarca a un conjunto de receptores, algunos asociados a los efectos terapéuticos y otros a los secundarios y toxicidad. Los fármacos antipsicóticos son un ejemplo de compuestos eficaces que se caracterizan por unirse a varios receptores simultáneamente (principalmente a receptores unidos a proteína G, GPCR). El trabajo de la presente tesis se ha centrado en el estudio de los mecanismos moleculares que determinan el perfil de afinidad de unión por múltiples receptores de los fármacos antipsicóticos.En primer lugar se construyeron modelos de homología para todos los receptores potencialmente implicados en la actividad farmacológica de dichos fármacos, usando una metodología adecuada para construir complejos fármaco-receptor consistentes. La estructura de estos complejos fue analizada y se llevó a cabo una comparación mediante métodos estadísticos multivariantes, que permitió la identificación de asociaciones entre la actividad farmacológica de los fármacos antipsicóticos y diferencias estructurales de los receptores diana. Los resultados obtenidos tienen interés para ser explotados en el diseño de fármacos antipsicóticos con un perfil farmacológico óptimo, más seguros y eficaces. Receptor 5-HT2A Receptor D3 Receptor D2 Ligando Clozapina Derivados Benzofuranonas Risperidona Olanzapina esquizofrenia métodos de regresión campos de interacción Molecular (MIF) Perfil Multireceptorial modelado por homología Docking sitio de unión interacciones moleculares selectividad afinidad de unión Diana Meta-Diana efectos secundarios fármaco antipsicótico típico fármaco antipsicótico atípico agonista antagonista membrana receptoroma rhodopsina estructura de rayos X descriptores moleculares farmacología análisis multivariante procedimiento integrado Computer-aided drug design Integrated approach Multivariate analysis Pharmacology Molecular descriptors X-ray structure Rhodopsin Receptorome Membrane Antagonist Agonist Atypical antipsychotic drug Typical antipsychotic drug Side effects Off-target Target Selectivity Binding affinity Molecular interactions Binding site Homology modeling Docking Multireceptor profile Molecular interaction Field (MIF) Partial Least Squares (PLS) Principal Component Analysis (PCA) Schizophrenia Benzolactam Derivatives Benzofuranone Derivatives Risperidone Olanzapine Clozapine Ligand Adrenergic receptors Muscarinic receptors Histamine receptors Serotonin receptors Dopamine receptors beta2-Adrenergic receptor D2 receptor D3 receptor 5-HT2A receptor G protein-coupled receptors (GPCR) 57

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