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Circadian system in peripheral clock in neurodegenerative disorder and affective disorder and their synchronization in constant light condition
Weissová, Kamila ; Kopřivová, Jana (advisor) ; Kemlink, David (referee) ; Svoboda, Jan (referee)
Summary: The circadian system plays an important role in human physiology and pathophysiology. It controls all processes that repeat in our body within a 24-hour period. It is a complex system that works from the behavioral level to the molecular level. This system is controlled from the central brain structure located in the hypothalamus, but its rhythmic manifestations can also be observed in almost any individual body cells. Disruption of this system in humans is often associated with the development of affective disorders or neurodegenerative diseases. The affective disorder has often been associated with a phase shift in some of the circadian driven outputs, as for example, rhythm in their physical activity. The patients with neurodegenerative disorders are seen to have circadian amplitude damping in a series of circadian rhythms. Therapeutic approaches which aim to stabilize and strengthen the circadian rhythms have also a positive long term effect on the course of these diseases. Interestingly, in the genetic studies of these diseases, a couple of specific polymorphisms have been identified in areas related to the molecular mechanism of the internal clock. In this thesis, I tried to look at the human circadian rhythms from several different angles. In the first part of this thesis I tried to identify...
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Relationship between circadian rhythms and selected biopsychosocial phenomena in healthy and clinical population
Fárková, Eva ; Kopřivová, Jana (advisor) ; Kunešová, Marie (referee) ; Sumová, Alena (referee)
Introduction: Circadian rhythms are typically manifested by individual timing of the sleep-wake cycle, expressed as a specific chronotype. Social jet-lag (SJL) is a phenomenon related to circadian preference as it reflects the phase misalignment of internal biological and external social time. SJL occurs when a person does not have the opportunity to fall asleep and get up in accordance with chronotype. Chronotype and SJL are phenomena that have recently been increasingly associated with the pathogenesis of sleep disorders and many civilization diseases, especially diseases of metabolic system. Aims and objectives: The aims of the thesis were: 1/ To determine chronotype and social jet-lag and observe further links between sex, age, BMI and other parameters in a selected sample of the Czech population across socio-demographic categories. 2/ To find out whether chronotype and the SJL play a role in the treatment of obesity. 3/ To revise the commonly used methods for chronotype assessment (questionnaires and actigraphy) for their future use in the Czech environment. Material and methods: The thesis consists of three follow-up studies (questionnaire, actigraphic and combined). Both subjective and objective methods of chronotype and SJL assessment were used in the thesis. 1) The first study was a...
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Role of hippocampal neurons in creation of cognitive schemas and higher-order spatial relationships
Lebedeva, Maria ; Kelemen, Eduard (advisor) ; Kopřivová, Jana (referee)
The hippocampus is the key structure in formation of representations of space (cognitive maps) in rats. Formation of spatial representations of simple environments has been described in details, in this work we focused on emergence of a spatial map of a complex environment from individual simple maps. A radial-arm maze was used to model a complex environment, where each arm was surrounded by unique pattern of proximal visual landmarks. Long Evans rats were allowed to explore gradually four different arms of the maze in a sequence of three sessions. During the first and second sessions rats separately visited two novel pairs of neighboring arms (arms 1 and 2 in the first session, arms 3 and 4 in the second session). In the third session rats were exposed to a new combination of already familiar arms (arms 2 and 3) to study how the two hippocampal maps, acquired originally as independent of each other, are integrated as the rat learns about their spatial relationship. Rats were exposed to this sequence of three sessions twice - before and after sleep. The activity of hippocampal neurons was recorded using a microelectrode system during the maze exploration and sleep. Our first observations suggest that representation of a complex environment neither is a simple combination of preexisting individual...
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Acoustic stimulation of Slow wave sleep and its influence on consolidation of declarative memory in insomnia
Orendáčová, Mária ; Kopřivová, Jana (advisor) ; Kelemen, Eduard (referee)
Slow-wave sleep plays an important role in consolidation of declarative memory. From electrophysiological point of view, this process is dependent on a common occurrence and mutual integration of neocortical slow oscillations (< 1 Hz), hippocampal sharp-wave ripples (150-250 Hz) and thalamo-cortical sleep spindles (10-15 Hz). Previous studies demonstrated that periodic acoustic stimulation by pink noise pulses applied at frequency of sleep slow oscillation during slow wave sleep leads to prolongation of slow wave sleep and to enhancement in declarative memory performance in normal sleepers. Our study investigated this kind of periodic acoustic stimulation in its relation to sleep architecture and declarative memory of people suffering from insomnia due to which there often comes to a reduction in slow wave sleep which positively correlates with worsening of declarative memory performance. Our aim was to investigate if this kind of comparatively non-invasive brain stimulation has a potential to increase a total length of slow wave sleep and enhance declarative memory performance in insomnia. Our study revealed acoustic stimulation neither improved declarative memory performance nor it increased total length of slow-wave sleep. No positive association was found between level of declarative memory...
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The effect of psychedelics on sleep
Šachová, Pavla ; Kopřivová, Jana (advisor) ; Spišská, Veronika (referee)
Recently, psychedelic drugs gain attention thanks to their potential to cure depressive disorders, anxious states or addiction. They are not causing addiction, they are not toxic and they trigger neuroplastic changes in tens of minutes or hours, which are essential for therapeutic purposes and positively correlates with an onset of antidepressant effect. Neuroplastic changes are simultaneously the connecting link between psychedelic state and sleep. In sleep the higher rate of neuroplasticity is markable during slow-wave sleep (SWS), which duration is getting shorter in patients with mental illness. The marker o neuroplasticity is slow-wave activity (SWA), which is getting higher not only in SWS, but also after intoxication with psychedelics or after long-time using of antidepressants. So the effect of psychedelics on sleep can be described as positive and inciting its therapeutical potential. The thesis is focused on ketamine which is the most recent one as for the topic of neuroplasticity and sleep.
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Neuronal activity during stereotypical behavior in quinpirole induced animal model of Obsessive Compulsive Disorder (OCD)
Alexová, Daniela ; Valeš, Karel (advisor) ; Kopřivová, Jana (referee)
The main aim of this study was to determine the changes in neuronal activity of anterior cingulate cortex (ACC), orbitofrontal cortex (OFC) and medial prefrontal cortex (MPC) in rats sensitized to D2/D3 receptor agonist quinpirole (QNP) during exploration of enriched open field arena. During the experiment, the evaluation of behavioural changes induced by quinpirole sensitization were also assessed and compared to previous results. For the purpose of this study, twenty-two adult male Long-Evans rats were used. The half of the rats was sensitized to QNP by receiving daily subcutaneous injections of quinpirole (0,5 mg/kg) while the other half received saline. Both groups were habituated for ten days to open-field arena enriched with two metal objects. The behaviour of animals was videotaped and the data about locomotion and the number of visits of each locale was obtained. On the eleventh day, the part of saline and quinpirole treated groups explored the open-field arena (t = 5 min) while the other two subgroups were left as respective cage-controls. Immediately after the end of experiment, all rats were sacrificed, and the extracted brains were cryopreserved. To determine the changes in neuronal activity of selected brain regions, fluorescence in situ hybridization of immediate early gene Arc was...
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The effect of psychedelics on sleep
Šachová, Pavla ; Kopřivová, Jana (advisor) ; Spišská, Veronika (referee)
Recently, psychedelic drugs gain attention thanks to their potential to cure depressive disorders, anxious states or addiction. They are not causing addiction, they are not toxic and they trigger neuroplastic changes in tens of minutes or hours, which are essential for therapeutic purposes and positively correlates with an onset of antidepressant effect. Neuroplastic changes are simultaneously the connecting link between psychedelic state and sleep. In sleep the higher rate of neuroplasticity is markable during slow-wave sleep (SWS), which duration is getting shorter in patients with mental illness. The marker o neuroplasticity is slow-wave activity (SWA), which is getting higher not only in SWS, but also after intoxication with psychedelics or after long-time using of antidepressants. So the effect of psychedelics on sleep can be described as positive and inciting its therapeutical potential. The thesis is focused on ketamine which is the most recent one as for the topic of neuroplasticity and sleep.
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Role of sleep and elevated introhippocampal corticosterone level in consolidation of traumatic memory in rodents
Brukhnová, Alena ; Kelemen, Eduard (advisor) ; Kopřivová, Jana (referee)
Any disruption of homeostasis causes a stress response that serves to restore balance in the body. Stress hormone levels, such as glucocorticoids, strongly influence the consolidation of episodic memory dependent on the hippocampus. Sleep has beneficial effects on individual types of memory and is necessary for the proper course of consolidation of newly acquired information. Little is known, however, about neuronal processes of memory consolidation for a traumatic event. The topic of this work is to study the combination of these two factors and to determine the effect of elevated levels of corticosterone and sleep on the consolidation of traumatic memory in rats. The theoretical part of this work summarizes the knowledge about memory, sleep and stress. The practical part deals with the experimental procedure combining behavioral (fear conditioning), electrophysiological methods (EEG recording and determination of sleep stages) and pharmacological manipulation (intrahippocampal administration of corticosterone). In summary, we found the effect of high levels of corticosterone in the hippocampus on contextual memory consolidation and on the amount of slow wave sleep. These results can bring new features in the field of traumatic memory consolidation and associated post-traumatic stress disorder....
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Vliv klomipraminu a risperidonu na učení a flexibilitu u animálního modelu obsedantně kompulzivní poruchy
Radostová, Dominika ; Stuchlík, Aleš (advisor) ; Kopřivová, Jana (referee)
Chronic sensitization of dopamine D2/D3 receptors by agonist quinpirole (QNP) induces compulsive checking behaviour in rats, which is considered an animal model of obsessive-compulsive disorder (OCD). Previous study revealed deficit in cognitive flexibility in QNP sensitized rats. This thesis focused on determining if this cognitive flexibility deficit is ameliorated by co-administration of clomipramine (CMI), risperidone (RIS) or combination of both (CMI+RIS) to QNP treatment. Aversively motivated active place avoidance task on a Carousel maze with reversal was used. The number of entrances into a to-be-avoided shock sector was evaluated as measure of performance. Six treatment groups were used: control group, QNP group, CMI group, QNP/CMI combination, QNP/RIS combination and QNP/CMI/RIS combination. Surprisingly, when compared alone, significantly worse acquisition was observed for QNP group compared to control group. However, similarly to previous study, QNP group had a worse performance in a first reversal session compared to control group. When all groups were compared, only QNP/CMI group had worse initial learning compared to control group. In reversal learning, only QNP treated group had a significantly more entrances than control group in first reversal session. Results suggest that co-treatment...
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