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Food neophobia and food preference in rodents (Rodentia) and its interaction with social learning.
Rudolfová, Veronika ; Landová, Eva (advisor) ; Telenský, Petr (referee)
Neophobia (fear of novelty) is first protection from ingesting potentially dangerous food in rodents. After overcoming the fear an animal begins to sample the food (take small parts). The animal then forms an aversion to dangerous food and preference for safe and nutritionally favourable food on the grounds of its experience with its ingestion. These mechanisms of behaviour towards food can be learned individually but an individual's behaviour is also influenced by other animals, especially in social animals. Whether an individual will act on its own experiences and therefore learn or if it will learn from others, depends on the situation and the environment in which the animal currently is. Key words: food neophobia, food preferences, social learning, individual learning, Rodentia, Rattus
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Animal models of sporadic form of Alzheimer's disease
Popelíková, Anna ; Stuchlík, Aleš (advisor) ; Telenský, Petr (referee)
Alzheimer's disease is a severe illness affecting the elderly and its incidence increases markedly every year. To date, there is no effective treatment for this condition available, and the precise mechanism of the pathogenesis remains elusive (apart from the identification of certain genetic mutations as causes in a small percentage of cases). Also, no suitable animal model of this disease has been found so far. This paper provides a summary of non-transgenic models currently in use as well as newly introduced adepts, their characteristics and examples of their use in practice. It covers both rodent models mostly generated by external interventions to the brain tissue homeostasis of the experimental animals, and vertebrate species that have been reported to spontaneously develop Alzheimer's disease-like pathology: the so-called 'natural models'. Thus, this review might provide better orientation in the up-to-date progress of research of this disease.
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Flexibility in spatial cognition of rat
Staňková, Anna ; Svoboda, Jan (advisor) ; Telenský, Petr (referee)
5 Abstract Cognitive flexibility is an ability to adapt a behavior according to a dynamic changes in an environment. It belongs to executive functions, along with the processes of working memory, attention, motivation and others. Flexibility is important in the process of changing "stimulus-response" contingency at the time when the initial stimulus no longer leads to reward. According to the nature of the changes we can distinguish three types of cognitive flexibility: reversal learning, intradimensional set shifting and extradimensional set shifting. The processes of cognitive flexibility take place in fronto-striato-thalamic circuit with numerous connections to other brain regions, especially the limbic system. Deficit in cognitive flexibility belongs among cognitive symptoms of schizophrenia, a psychiatric illness we studied in the experimental part of this work using its analogue in rat. The aim of the experimental work was to test cognitive flexibility deficit in the rat model of schizophrenia-like behavior in the Carousel maze in four versions of task with different cognitive load. Animal model of schizophrenia was induced by acute administration of non-competitive NMDA receptor antagonist MK-801 at doses of 0.05 and 0.10 mg/kg i.p. Reversal learning was not damaged in this type of task following the...
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Morphological changes of the hippocampus in tetanus toxin model of temporal lobe epilepsy
Demeterová, Ľubica ; Jiruška, Přemysl (advisor) ; Telenský, Petr (referee)
Temporal lobe epilepsy is the most common form of epilepsy and hippocampal sclerosis represents the main underlying structural abnormity. Approximately 20% of TLE cases are non- lesional due to absence of any obvious epileptogenic lesion and tetanus toxin model is traditionally considered as a model of non-lesional temporal lobe epilepsy. The main aim of this study was to evaluate the presence of the cell damage and to determine its spatiotemporal profile. Tetanus toxin was stereotaxically injected into CA3 subregion of dorsal hippocampus in adult male Wistar rats. Brain tissue was extracted 4, 8 and 16 days following the surgery. Postfixed brains were sectioned to 50 µm slices and labeled using Nissl's and FluoroJade B staining (FJB). Hippocampal sclerosis was present only in animals from D16 group, however, it was localized mainly in contralateral CA1 area. Additional finding was decreased Nissl's staining in contralateral hippocampus which corresponded with the presence of FJB positive neurons. In animals from group D8, we have identified presence of FJB positive neurons predominantly in ipsilateral hippocampus. In D4 animals, cellular degeneration was absent. To examine the non- lesional nature of tetanus toxin model, we have performed blind study, when Nissl's staining were reviewed...
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Olfactory bulbectomy in laboratory rat as an animal model of depression
Entlerová, Marie ; Stuchlík, Aleš (advisor) ; Telenský, Petr (referee)
Removal of olfactory bulbs (olfactory bulbectomy; OBX) belongs amongst most interesting experimental phenomenons, which stimulated interesting hypotheses about the role of this structure in the CNS functions. It outreaches also to the preclinical research as an the animal model of depression-like behavior (usually pursued in the laboratory rats). Significance and all sequelae of olfactory bulbectomy probably cannot be covered in their extents by this thesis, therefore, I will first focus on short neuroanatomical description of connections between the olfactory bulbs and the limbic system, and short description of the OBX surgery will follow. Subsequently, I will discuss structural, molecular and neurochemical changes elicited by OBX. Next part of this work will be dedicated to OBX in relation to behavior; first I will present behavioral changes elicited by OBX with focus on learning and memory (and other cognitive functions) and then I would brieflysummarize the putative (for example endocrine, imunne) changes, witch can will be cause followin OBX. In conclusions, I will discuss usage of OBX as an animal model of depression.
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Immediate early genes as a tool for study of spatial orientation and memory
Bláhová, Veronika ; Němec, Pavel (advisor) ; Telenský, Petr (referee)
Properties of the environment, spatial orientation cues and time-shifting movements are essential for cognitive maps. The understanding of how both space and the animal's position within that space are represented in the brain has been significantly advanced by the discoveries of four principal neuronal types: the place cells, the head direction cells, the grid cells and border cells. Their activity being driven by both allothetic (visual and non-visual landmarks), and idiothetic cues (internal movement cues based on proprioceptive and vestibular information). Brain regions containing aforementioned types of neurons constitute complex spatial representation system. Immediate early genes (IEGs) and their products became sophisticated tool for the study of neural substrate of spatial orientation including magnetic orientation. For further research it is unavoidable to uncover the dynamic of processes related to IEGs in order to better understanding the functions of brain centres involved in rodent navigation circuit. This work summarises our knowledge about spatial orientation of the vertebrates aimed at rodents, in context with detection of IEGs expression as activity markers in neural substrate. There are described most common experimental mazes and most frequent detection methods used in connection with...
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The effect of partial agonist of serotonin-1A receptor on cognitive functions in animal model of schizophrenia
Antošová, Eliška ; Valeš, Karel (advisor) ; Telenský, Petr (referee)
Serotoin is a neurotransmitter participating in regulation of many physiologic fuctions. Main serotogenous neurons can be found in nukleus raphe of the brain stem. Nucleus raphe inervates many areas of the brain including the cerebal cortex and hipocampus. These structures are important for controling of higher cognitive functions. 5HT1A receptor is one of many subtypes of serotonin receptors and its activation inhibits iniciating of the action potencials. 5HT1A receptor is expressed presynapticaly as an autorecpetor in nucleus raphe. Activation of 5HT1A receptors decreased the output of the serotonin in the target structures. This key position enables to regulate the serotonin level in the brain. 5HT1A receptor can be found also postsynapticaly as an heteroreceptor in the hippocampus and in the brain cortex, where it affects the output of many other neurotransmitters. Experimental studies indicate that affecting of the 5HT1A function can improve many neuropsychiatric disorders such as schizophrenia, anxiety, depresion and it can also moderate the congitive deficit. It is supposed that the activation of 5HT1A autoreceptors and the inhibition of 5HT1A heteroreceptors can positively affect the cognigtive abilities. It seems that 5TH1A autoreceptors are more sensible for pharmacologic influence. Thus in these...
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Spatial orientation in reptiles focused on methods of testing of allothetic navigation
Voňavková, Monika ; Landová, Eva (advisor) ; Telenský, Petr (referee)
Recently are known several different navigational systems in reptiles, mainly large scale navigational abilities based on sun and magnetic compass. The turtles are frequently used species in studies of spatial cognition, however, informations about spatial cognitive abilities in snakes and lizards (order Squamata) are only a few. Current knowledge concerning mechanism of small scale navigation based on allothetic orientation in snakes and lizards is only poorly understood. Aim of this thesis is review the literature about the mechanisms of reptile spatial orientation focused on allothetic navigation (using of external landmarks). As extension of this thesis is review of the principles of testing allothetic orientation in other groups (e. g. mammals) that were frequently used as a subject for testing allothetic orientation). The design of tests of allothetic orientation in model species of lizards (Eublepharis macularius) is one of the results of this thesis. Keywords: reptiles, spatial orientation, allothetic navigation
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The effect of prefrontal and posterior parietal lesion on behavior in behavioral tests of spatial cognition
Vodička, Martin ; Telenský, Petr (advisor) ; Svoboda, Jan (referee)
The effect of prefrontal and posterior parietal lesion on behavior in behavioral tests of spatial cognition In this thesis we examined the effect of prefrontal and posterior parietal cortex lesions on rat behavior. Medial prefrontal cortex is involved in working memory, behavioral flexibility and coding of spatial goals. Rats were tested in carousel maze in room frame reversal task and consequently in arena frame task on dark arena. We observed, that the lesion of medial prefrontal cortex did not disrupt the reversal learning task, but the rats were impaired in initial learning of the task. No difference was found in arena frame task. Posterior parietal cortex has a role in attention processes and takes part in processing spatial information and long term memory. Rats with bilateral lesion of posterior parietal cortex were tested in battery of tests on carousel maze (reversal learning, double avoidance) and in Morris water maze (distal landmark version and modified version with intramaze landmarks). Lesioned animals were impaired in carousel maze task in reversal learning of room frame represetation. This effect was confirmed in double avoidance task, where lesioned animals had more entrances into room frame than the controls. In Morris water maze task, lesioned animals were impaired in intramaze...
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Applications of multiple reference frames environments in behavioral research
Telenský, Petr ; Bureš, Jan (advisor) ; Němec, Pavel (referee) ; Otáhal, Jakub (referee)
This work has been motivated by the desire to enhance our knowledge about specific cognitive requirements of navigation in multiple reference frames environments and to understand the roles of the hippocampus and posterior parietal cortex in this behavior. The main conclusions of this thesis are: (a) We have developed a novel behavioral test called the Enemy Avoidance Task. The initial set of experiments has shown that laboratory rats are able to plan their movement with respect to a to-be-avoided moving object. Behavioral performance in the task may be quantitatively evaluated. (b) The aforementioned ability is crucially dependent on the functional integrity of the dorsal hippocampus. To the contrary, functional inactivation of the dorsal hippocampi by local infusion of tetrodotoxin did not cause any impairment in the ability of the animal to estimate its distance from a non-moving object. The finding suggests a specific role of the hippocampus in dynamic cognitive processes required for flexible navigation strategies such as continuous updating of information about the position of a moving stimulus. These results are at odds with the two major theories of hippocampal function (Cognitive map theory and Declarative memory theory) and therefore suggest that revision of the theories is necessary. (c)...
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