|
|
Stimulant drugs and their physiological effects
Nováková, Pavlína ; Novotný, Jiří (advisor) ; Hejnová, Lucie (referee)
The category of stimulant drugs is a heterogenous group of substances which benefit-to-harm ratio varies widely. This work attempts to use a systemic approach in order to characterize the underlying basis of the physiological effects of their selected representatives in brain. A brief pharmacological description of caffeine, nicotine, cocaine, amphetamine and methamphetamine is followed by an identification of main molecular targets of these drugs in the context of respective neurotransmitter systems. Major attention is given to both acute and chronic molecular mechnisms of action of the selected stimulant drugs up to the level of selected relevant neural circuits. In the next section stimulant drugs are presented as Trojan horses that attack the motivational system of the brain. Initially, a theoretical analysis of reward together with a neuroanatomical dissection of reward-related circuitry serves as a basis for the formulation of contemporary theories of drug addiction. Finally, an effort is made to synthesize common molecular events with specific aspects of reward in order to draw a picture of the neurobiological view of addiction.
|
|
|
Interval Timing and Emotional Modulation
Šafránková, Kristýna ; Nekovářová, Tereza (advisor) ; Telenský, Petr (referee)
This bachelor thesis focuses on time perception, a field of study pursued extensively by psy- chologists, neuroscientists, and cognitive linguistic researchers. More specifically, this paper will examine the issue of "interval timing" (i.e. an individual's ability to perceive time intervals in seconds or minutes). Time perception is influenced by several factors, of which emotional modulation has been postulated as the most crucial. Examining the physiological mechanisms of emotional modulation and pacemaker-accumulator, the striatal model of time perception along with its role in emotional modulation form the contributions of this thesis. Key words: interval timing, dopamine, emotions, the striatal beat-frequency model
|
|
|
Porous Boron-Doped Diamond Electrodes: Characterisation and Application for Electroanalysis
Baluchová, Simona
This dissertation thesis presents newly developed electrode materials based on porous boron- doped diamond (BDDporous) and their potential applications in electroanalysis. Particularly, these novel BDDporous electrodes (twelve in total) were thoroughly electrochemically characterised and compared, and the ones with the most promising properties were selected to develop reliable voltammetric methods for detecting the neurotransmitter dopamine. Initially, the impact of selected fabrication parameters on the final properties and electrochemical behaviour of novel BDDporous electrodes was clarified; the following factors were specifically studied: (1) deposition template used, (2) boron-doping level, (3) growth time of the individual layers (i.e., porosity), (4) number of deposited layers (i.e., thickness), and (5) content of non-diamond (sp2 ) carbon impurities. Alterations in deposition conditions naturally resulted in BDDporous electrodes with diverse (i) structural and morphological features, which were investigated by scanning electron microscopy and Raman spectroscopy, and (ii) physical and electrochemical characteristics, examined by cyclic voltammetry. Besides, to assess the suitability of selected BDDporous electrodes for dopamine detection, other parameters, such as susceptibility to...
|
|
|
Porous Boron-Doped Diamond Electrodes: Characterisation and Application for Electroanalysis
Baluchová, Simona ; Schwarzová, Karolina (advisor) ; Navrátil, Tomáš (referee) ; Šelešovská, Renáta (referee)
This dissertation thesis presents newly developed electrode materials based on porous boron- doped diamond (BDDporous) and their potential applications in electroanalysis. Particularly, these novel BDDporous electrodes (twelve in total) were thoroughly electrochemically characterised and compared, and the ones with the most promising properties were selected to develop reliable voltammetric methods for detecting the neurotransmitter dopamine. Initially, the impact of selected fabrication parameters on the final properties and electrochemical behaviour of novel BDDporous electrodes was clarified; the following factors were specifically studied: (1) deposition template used, (2) boron-doping level, (3) growth time of the individual layers (i.e., porosity), (4) number of deposited layers (i.e., thickness), and (5) content of non-diamond (sp2 ) carbon impurities. Alterations in deposition conditions naturally resulted in BDDporous electrodes with diverse (i) structural and morphological features, which were investigated by scanning electron microscopy and Raman spectroscopy, and (ii) physical and electrochemical characteristics, examined by cyclic voltammetry. Besides, to assess the suitability of selected BDDporous electrodes for dopamine detection, other parameters, such as susceptibility to...
|
|
|
The influence of central serotoninergic and dopaminergic activity on nutritional and metabolic parameters
Brunerová, Ludmila ; Anděl, Michal (advisor) ; Haluzík, Martin (referee) ; Yamamotová, Anna (referee)
THE INFLUENCE OF CENTRAL SEROTONINERGIC AND DOPAMINERGIC ACTIVITY ON NUTRITIONAL AND METABOLIC PARAMETERS MUDr. Ludmila Brunerová SUMMARY Introduction: Neuromediators dopamine and serotonin play a significant role in homeostatic and hedonic regulation of food intake, may exert direct metabolic effects and particularly serotonin influences affectivity. Their central activity could be quantified by functional tests. Common regulatory mediators of metabolism and affectivity represent an interesting research goal. Aims of study: The first aim was to describe the relationship between central serotoninergic activity measured by citalopram challenge test, affectivity, preference of macronutrients in food and metabolic profile in healthy men. The second aim was to confirm the use of sublingual apomorphine test as a functional test for assessment of central dopaminergic activity. The third aim was to reveal the relationship between central dopaminergic activity measured by sublingual apomorphine test, preference of macronutrients and metabolic profile. Methods: The study was performed on 42 healthy men (average age 43.5 ± 7.4 years and average BMI 27.4 ± 5.7 kg/mš) within 4 days with a week interval in between them. Anthropometric and...
|
|
|
Study of surface modifications of boron doped diamond electrode for voltammetric detection of dopamine and serotonin
Eremina, Anna ; Schwarzová, Karolina (advisor) ; Dejmková, Hana (referee)
This diploma thesis deals withthe studyof electrochemical behaviorand detection of two structurally different neurotransmitters, dopamine (DA) and serotonin (5-HT), in solutions commonly used for neuron cultivation, namely Neurobasal (NB), NB with phenol red and in phosphate buffer (PB) of a pH close to the physiological value. An electrode based on boron-doped diamondwas used for the study, examiningtwo types of surfaces obtained after oxidation (O-BDD) and mechanical polishing (p-BDD). The results were obtained by two voltametric techniques,namely cyclic and differential pulse voltammetry.The studyrevealedthat DA oxidationis a quasi-reversible process,whereas 5-HT oxidizes irreversibly on O-BDD and p-BDD. Nevertheless, for both neurotransmitters their anodic oxidationonboth BDD surfaces is controlledby diffusion. Due to the passivation of the electrode surface by the oxidation products, anodic reactivation(Eact = +2400 mV, t = 30 s) was first testedto regenerate the O-BDD surface during DA and 5-HT measurements. There was no continuous decrease in DA peak currents on O-BDD and the measuredsignals were characterizedby high repeatabilityin all studiedmedia (sr (Ip) 1.1% in PB of pH 7.0, 1.7% in NB of pH 7.34, 0.9% in NB with phenol red of pH 7.48). In the case of 5-HT, the anodic reactivation was...
|
|
|
Modification of boron doped diamond electrode by poly-L-lysine and its influence on electrochemical behaviour of dopamine and serotonin
Pejzlová, Michaela ; Fischer, Jan (advisor) ; Vyskočil, Vlastimil (referee)
This bachelor's thesis deals with the redox behavior of two neurotransmitters, dopamine and serotonin, at bare anodically activated (O-terminated) and poly-L-lysine-coated boron doped diamond electrode in two media, namely phosphate buffered saline and Neurobasal (medium commonly used for neuron cultivation experiments). Oxidation of dopamine in tested environments has a quasi-reversible character, while serotonin oxidizes irreversibly on boron doped diamond electrode, both O-terminated and poly-L-lysine-treated. Clearly, poly-L-lysine modification of boron doped diamond electrode leads to a decrease in peak currents and a positive shift in oxidation potentials compared to the O-terminated boron doped diamond electrode; interestingly, serotonin is much more sensitive to polymer coating than dopamine, particularly in Neurobasal medium. During successive measurements, a considerable decrease in recorded signals of both neurotransmitters can be observed. Hence, possibilities how to ensure stable current values were investigated: for dopamine, stirring the solution between the individual scans is sufficient method for obtaining repeatable signals (sr = 1.4-11.9 %, n = 5). However, in case of serotonin it is necessary to reactivate the electrode surface anodically in H2SO4 (Eact = +2400 mV) for 5...
|
|
| |
|
|
Neuropharmacology of spatial navigation, cognitive coordination and flexibility tests in animal models
Prokopová, Iva ; Stuchlík, Aleš (advisor) ; Vyklický, Ladislav (referee) ; Blahoš, Jaroslav (referee)
Spatial navigation, cognitive coordination and behavioral flexibility belong amongst cognitive functions, which play a role in many neuropsychiatric disorders. Behavioral tasks have proved to be useful paradigms to test these functions in pharmacological or genetic animal models. First aim was to determine a potential interaction between β-adrenergic and α1-adrenergic or D2-dopaminergic systems. Spatial navigation and coordination were impaired in both studies during co-aplication of subthreshold doses of drugs. Used substances belong to group of widely prescribed drugs, thus our results could be implicated in clinical practice. Another study examined an acute effect of MK-801 (animal model of schizophrenia) on behavioral flexibility in Carousel maze and the Morris water maze (MWM). Carousel maze showed higher sensitivity with impairments from 0.08 mg.kg-1 compared to 0.10 mg.kg- 1 in MWM. The final experiment aimed at testing the effect of reduced expression of Nogo-A protein on spatial navigation and behavioral flexibility of rats. A battery of tests in the Carousel maze revealed impairment in cognitive functions, MWM showed unaffected working memory of rats. Our results support the hypothesis linking Nogo-A knock-down rats with neuropsychiatric symptoms and cognitive disorders. Key words:...
|
|
|
Rheological properties of modified polymer-composite bone pastes
Hlináková, Kristýna ; Vojtová, Lucy (referee) ; Michlovská, Lenka (advisor)
Předložená diplomová práce je zaměřená na studium viscoelastického chování kostních past na bázi fosforečnanu vápenatého a vodného roztoku termosenzitivního triblokového kopolymeru, zlepšujícího tokové vlastnosti pasty. V teoretické části je zpracována stručná charakteristika cementů na bázi fosforečnanu vápenatého. Rovněž se zabývá charakteristikou reologických vlastností injektabilních kostních past. Součástí je také stručný přehled aditiv ovlivňujících právě reologické a mechanické vlastnosti past. Experimentální část je zaměřena na charakterizaci triblokového kopolymeru pomocí nukleární magnetické rezonanční spektroskopie a reologie. Dále byly připravovány modifikované fosfátové cementy, u kterých byly posléze studovány viskoelastické vlastnosti. Kostní pasta byla modifikována přídavkem adhezivních sloučenin (dopamin a jodičnan sodný) a antibakteriálním činidlem (selenové nanočástice). Analýza viskoelastických vlastností byla provedena reologickou analýzou, během níž byl primárně sledován proces vytvrzování a tixotropní chování jak nemodifikovaných, tak modifikovaných fosfátových past. Proces vytvrzování probíhal při teplotě 23 °C a 37 °C, imitující fyziologické prostředí. Morfologie fosfátové keramiky byla charakterizována pomocí rastrovací elektronové mikroskopie a velikost částic byla zjištěna pomocí laserového analyzátoru částic. Bylo prokázáno, že výše zmíněná aditiva mají pozitivní vliv na kinetiku procesu vytvrzování kostních past. Selenové nanočástice navíc vylepšily tixotropní chování polymer-fosfátových past. Z tohoto důvodu jsou tyto nové injektabilní kompozitní pasty vhodné pro miniinvazivní chirurgii. Díky aditivům, vykazujících adhezivní vlastnosti, mají potenciál uplatnit se při léčbě zlomenin. Stejně tak se nabízí možnost využít pasty při léčbě osteomyelitidy, a to díky možnému uvolňování antibakteriálních nanočástic.
|
guest ::
