|
|
The role of the m6A pathway on electrophysiological correlates of spatial memory in animal model of Alzheimer's disease
Karkušová, Patrícia ; Telenský, Petr (advisor) ; Hromádka, Tomáš (referee)
Memory is one of the vital cognitive functions and can be divided into two categories, short-term memory and long-term memory. Long - term memory is further divided into explicit (declarative) for facts and events and implicit (non-declarative) memory, covering all other types of long-term memory. Alzheimer's disease is well known for a gradual loss of declarative memory and spatial orientation. It is one of the most common causes of dementia and affects tens of millions of people worldwide. The aim of our study was to determine the effect of inhibition of FTO demethylase on neuronal activity in a rat model of Alzheimer's disease (TgF344-AD) and a control strain (F344-CT), and evaluate the stability of spatial maps. We used tetrodes implanted in hippocampal CA1 subregion to record extracellular neuronal activity. Spiking activity was recorded in two spatially different conditions (familiar, unknown) twice, before and after applications of pharmacological inhibitor of FTO demethylase (MO-I-500). We have also evaluated remapping and map stability related to the application of MO-I- 500. We found the average frequency of neuronal firing rate increased in F344-CT rats in both familiar and novel environments after inhibitor administration, whereas increase in TgF344- AD rats was detected only in the novel...
|
|
|
The origin of specific phobia from spiders: Neurophysiological mechanisms vs. testing the assumptions of evolutionary theories explaining the origin of specific phobia from spiders
Hladíková, Tereza ; Landová, Eva (advisor) ; Telenský, Petr (referee)
Spider phobia is one of the most frequent specific animal phobias in the population. There are two key emotions in the origin of spider phobia: fear and disgust. Several theories of spider phobia origin were proposed and so the results and interpretations of these studies, which test prerequisites of these particular theories often vary. Studies focusing on psychophysiological measurements such as changes in heart activity or skin resistance, show differences in emotion intensity in phobics compared to non-phobics. The second group of studies concerning the analysis of proximate mechanisms attempts to uncover the brain activity during phobic stimulation. These studies mostly agree on the coordination of the cognitive control network and the fear-network with the key role of the amygdala and insula in the phobic reaction. Other studies which test prerequisites of evolutionary theories examine e.g. heritability of specific phobias, speed of spider detection or easier learning and extinction of fear of spiders. The aim of this bachelor thesis is focused on the results of studies uncovering the proximate neurophysiological and psychophysiological mechanisms of specific spider phobia and to discuss these results in relation to the paradigm of evolutionary theories about the origin of this phobia. It is...
|
|
|
Locomotor, emotional and cognitive skills of laboratory Norway rats with different early ontogenetic experience with social play
Petr, Tomáš ; Špinka, Marek (advisor) ; Telenský, Petr (referee)
In the contemporary research of playful behavior in animals, it has not yet been reliably tested whether the experimental limitations of play in the critical phase of ontogenesis will have a negative effect on motor, emotional and cognitive skills in the later stages of an individual's development. In this thesis, we try to separate the influence of kinematic and social limitations of play experience by comparing three treatments of Long-Evans laboratory rats, in which rats were exposed to different play experience in the period between the 24th and 66th postnatal day. In this early period of ontogenesis, all male rats were allowed to play for one hour a day. According to the treatment, it was either modified the rats' play environment or the play was reduced by a socially less playful partner. In full-play treatment, the Long-Evans focal laboratory rat was allowed to play in the full extent of movement in the entire environment of a play arena. The play was enabled throughout the whole experiment with a partner of same Long-Evans strain. The same strain paired arrangement for the play was present in the second treatment with kinematically-reduced play, however the space for the play behavior was limited by a radical lowering of a ceiling of the play arena to such an extent that any three-...
|
|
|
Genetic knockout of CS4 sulfation of perineuronal nets as a source of juvenile like plasticity in processes of memory and learning
Gmiterková, Lenka ; Růžička, Jiří (advisor) ; Telenský, Petr (referee)
Extracellular matrix affects the functioning of the brain. Among others, learning and memory can be affected by the changes in the composition and properties of the extracellular matrix. Different sulfation patterns on the chondroitin sulfate proteoglycans, one of the extracellular matrix components, can either enhance or reduce synaptic plasticity and neuronal growth. This leads to the changes in the formation of memory. In my thesis I defined the role of 4-O-sulfation of the chondroitin sulfate proteoglycans in the learning and memory in the young and early adult animals. To do so I used Chondroitin sulfotransferase 11 knockout mice strain, which has decreased amount of 4-O-sulfation. I tested their long-term, short-term, and working memory using behavioural tests. I also monitored the morphological changes in the perineuronal nets and changes in the number of synapses using immunohistochemical methods and confocal microscopy.
|
|
|
EEG correlates of egocentric and allocentric distance estimates in virtual environment in humans
Kalinová, Jana ; Vlček, Kamil (advisor) ; Telenský, Petr (referee)
Cognitive processes associated with spatial orientation can use different reference frames: egocentric, centered on observer and allocentric, centered on objects in the environment. In this thesis, we use EEG to investigate the dynamics of brain processes accompanying spatial orientation based on these reference frames. Participants were instructed to estimate distances between objects or themselves and objects located in a virtual circular arena; this task was presented in both 2D and 3D displays. Task-related EEG changes were analyzed using a time-frequency analysis and event-related potential analysis of 128-channel EEG recordings. Through time-frequency analysis we found significant power differences in delta, theta, alpha, beta and gamma bands amongst the control, egocentric and allocentric testing conditions. We noted a decrease in alpha power in occipital and parietal regions, while a significantly stronger decrease was observed for the allocentric condition compared to both egocentric and control conditions. A similar pattern was also detectable for the beta band. We also report an increase in theta and delta power in temporal, fronto-temporal and lateral frontal regions that was significantly stronger for the egocentric condition compared to control and, in some electrodes, even...
|
|
|
Brain energy metabolism and its pathologies
Nová, Jana ; Telenský, Petr (advisor) ; Kolář, David (referee)
The brain belongs amongst metabolically most active organs and disturbances of brain energy metabolism are commonly cited as a critical factor predisposing to neurodegeneration. Brain metabolic substrates must be strictly regulated both spatially and temporarily to ensure the energy homeostasis of the brain. Research on energy metabolism of the brain identified several models revealing the interdependence of metabolic processes in the CNS. Powered by TCPDF (www.tcpdf.org)
|
|
| |
|
|
Effect of stress on expression of glucocorticoid receptors and enzymes of glucocorticoid metabolism in specific structures of rat brain
Kvapilová, Pavlína ; Pácha, Jiří (advisor) ; Telenský, Petr (referee)
Stress response is trigerred by a number of factors, which, depending on the type of response they generate, involve different brain structures. These structures then relay the information to the paraventricular nucleus of hypothalamus (PVN), which is the main integration center for information about the imbalance of homeostasis induced by stressors. If it meets a sufficient number of excitatory signals, the PVN activates the hypothalamic pituitary adrenal axis, which ultimately triggers the secretion of stress hormones glucocorticoids, which then act back on the brain. This action is influenced by several factors, mainly the presence of local metabolism of glucocorticoids. Local metabolism is provided by the enzymes 11-hydroxysteroid dehydrogenases, which can locally activate or deactivate the hormone molecules and thus amplify or attenuate their effects.
|
|
|
Matching the role of chondroitin sulphate proteoglycan, aggrecan, in dense extracellular matrix of perineuronal nets and glial scar
Gmiterková, Lenka ; Růžička, Jiří (advisor) ; Telenský, Petr (referee)
Traumatic brain and spinal cord injuries are worldwide medical problems. Disruption of the tissue leads to the changes in the cellular and extracellular matrix composition. This newly formed scar is not permissive for the axonal regrowth. Its function in prohibiting neuronal plasticity is similar to the perineuronal nets present in undamaged brain. One of the key components of both perineuronal nets and scar is proteoglycan aggrecan. In this thesis I focused on the function of aggrecan in central nervous system, mechanism of its growth inhibitory feature and research in the field of traumatic brain or spine cord injury treatment. It is important topic, since currently there are not any approved human therapies to recover axonal growth at the site of formed scar.
|
|
|
Role of ventral hippocampus and medial prefrontal cortex in behavioral flexibility in rodents
Černotová, Daniela ; Svoboda, Jan (advisor) ; Telenský, Petr (referee)
Behavioral adaptation to a continuously changing environment is critical for the survival of the animals, but also day-to-day interactions in the human world. The main components maintaining flexibility in cognition and behavior are well-established and depend mostly on proper intercommunication within the prefrontal cortex (PFC) and striatum. Some parts of the PFC are densely innervated by the ventral hippocampus (vHPC), which has a great impact on its functioning. Also, hippocampal-prefrontal circuit dysfunction has been shown to disrupt the integrity of flexible cognition in some neuropsychiatric diseases. Therefore, the exact functional role of this pathway is an indispensable part of the research. The aim of this study was to test the role of the vHPC and the medial PFC (mPFC) in an active place avoidance task on a rotating arena in 1) two flexibility task variants - reversal learning and set- shifting - and 2) the spatial memory retrieval. We inactivated these structures by muscimol (GABAA receptor agonist) in a variety of unilateral, bilateral, and combined local injections. Disrupted performance was apparent in reversal learning in vHPC-inactivated rats. No effect was seen in mPFC-inactivated rats. Impairments after the task acquisition were observed in bilateral vHPC and mPFC inactivations...
|
guest ::
