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Circadian regulation of STAT3 protein in the SCN and it's activation by leptin in the SCN, other parts of hypothalamus and the pineal gland
Moníková, Veronika ; Bendová, Zdeňka (advisor) ; Jelínková, Dana (referee)
JAK/STAT signaling pathway is one of the most studied intracellular cascades transmitting signals from the extracellular environment to the cell nucleus in order to affect expression of target genes. Circadian clocks localized in the suprachiasmatic nuclei (SCN) of the hypothalamus are sensitive especially to light but they can respond to non-photic stimuli such as growth factors, opioids, leptin and cytokines that have been demonstrated to perform its function via the JAK/STAT signaling pathway. The recent findings of our laboratory demonstrated that STAT3 protein is highly produced by SCN of rat. Primary aim of our experiments was to test the circadian regulation of STAT3 production in SCN and describe the effect of exogenously administered leptin on STAT3 phosphorylation in the SCN, pineal gland and hypothalamic structures responsible for regulated feeding behavior and energy metabolism. Because activation of leptin receptors may stimulate a number of other signaling cascades, we chose phosphorylated forms of kinase ERK1/2 and GSK-3β as other markers of intracellular changes after administration of leptin in the studied structures. Our results proved rhythmic production of STAT3 protein in SCN of rat and indicated circadian regulation of sensitivity to leptin in hypothalamic structures. The data...
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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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Experimental rat models in traumatic spinal cord injury research
Kloudová, Anna ; Machová Urdzíková, Lucia (advisor) ; Mrózková, Petra (referee)
A large number of spinal injuries that cause damage to the spinal cord occur every year. Such damage to spinal cord tissue leads to a number of dysfunctions that significantly reduce quality of life and therefore the development of effective therapies remains a very important issue. The use of animal models is considered the major tool of this research field, enabling the testing of new treatments as well as observing ongoing pathophysiological processes. Rats are the most frequently used animal model due to the many possible ways of creating a spinal cord lesion on them. The contusion model uses a computer-controlled device to simulate the spinal cord contusion and therefore is highly precise. However, a compression model seems to be the most suitable model for pathophysiological studying. Besides contusion it enables persistent compression to the spinal cord. Transection and hemisection methods are intended for axonal regeneration research, as only these models can reliably distinguish new growing fibers from the preserved ones. Less often photochemical and excitotoxic models are used. Lastly, dislocation and distraction of vertebrae or damage to the spinal cord using heat or cold can be carried out. Each of the models have their own unique features that make them optimal to use in different...
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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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Behavioral expression of pain in rats
Zámečník, Jakub ; Vaculín, Šimon (advisor) ; Boukalová, Štěpána (referee)
The aim of this work is to summarize the current knowledge regarding the behavioral expressions of pain in rat. The work is focused on rats, because they are one of the most used laboratory animals, and may experience pain in some experiments. Behavioral expressions of pain were selected, because they are quite easily recognizable and measurable. The reader will be first acquainted with the necessary basics associated with the phenomenon of pain, with its conception in animals, with classification, physiology and for example with the ways in which are in rats experimentally induced pain. Then in the second part, there are shown individual behavioral expressions with examples in which cases were these manifestations observed. So everyone who is interested can learn something about pain in connection with the avoidance reaction, pose, appearance, specific movements of rat, vocalization, changes in eating and drinking, changes in activity, anxiety, cognitive functions and many other expressions. The work can be valuable contribution for all workers with animals and with its character can contribute to animal welfare. Powered by TCPDF (www.tcpdf.org)
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Pathogenesis of hypercholesterolemia in Prague hereditary hypercholesterolemic (PHHC) rat
Rybáková, Kateřina ; Vlachová, Miluše (advisor) ; Poledne, Rudolf (referee)
Hypercholesterolemia represents a major risk factor of cardiovascular disease. A number of experimental models is used for study of hypercholesterolemia pathogenesis and therapy. This thesis concentrates on characterization of one of these models. Prague hereditary hypercholesterolemic (PHHC) rat is such a suitable model for study of hypercholesterolemia. Although the majority of plasma cholesterol is transported by high density lipoprotein in PHHC rat fed standard diet, PHHC rat fed cholesterol diet develops hypercholesterolemia comparable to that of humans. The advantage of this model is that hypercholesterolemia develops without the need for addition of bile acids or other hepatotoxic substances to the diet. The hypercholesterolemia of PHHC rat is caused by slowed down catabolism of cholesterol-rich very low density lipoprotein (VLDL). These cholesterol-rich particles are synthesized in the liver. We found out that PHHC rat fed 1% cholesterol diet accumulates cholesteryl esters (CE) in the liver and also in the VLDL. Acyl-CoA:cholesterol acyltransferase (ACAT) and microsomal triglyceride transfer protein (MTP) may participate in the increased incorporation CE into VLDL. We found out no difference in ACAT and MTP activities in the liver between PHHC rats and control animals. Neither ACAT activity...
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Echocardiographic assessment of left ventricular systolic function in rats adapted to hypoxia and exercise training
Hrdlička, Jaroslav ; Papoušek, František (advisor) ; Vybíral, Stanislav (referee)
- 4 - Abstract Adaptation to hypoxia or exercise training has cardioprotective effects against acute ischemic injury, but can potentially negatively influence heart function. Possible negative changes depend on the degree of hypoxia and exercise training intensity. It is therefore necessary to evaluate the effects of the specific adaptation protocols used. The ideal technique is echocardiography, which enables non-invasive, repeated and long-term measurements of the same individual allowing to study the development of changes in the course of adaptation. The aim of this study was to determine the effects of selected protocols of adaptation to intermittent hypobaric hypoxia (corresponding to the altitude of 4,000 to 8,000 meters above sea level, for 15 weeks in total) and exercise training (running speed 30 m.min-1 for 60 min a day, 4 weeks in total) on the left ventricle geometry and systolic function in rats. We assessed basic echocardiographic parameters of the ventricle geometry and function such as fractional shortening, ejection fraction, stroke volume, cardiac output etc. The adaptation of rats to intermittent hypobaric hypoxia lead neither to the impairment of systolic function nor to the development of left ventricle hypertrophy compared to controls; signs of moderate hypertrophy were observed only...
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The influence of status epilepticus (SE) in postnatal development early phase on laboratory rat psychomotor development
Boťchová, Lenka ; Kubová, Hana (advisor) ; Mareš, Pavel (referee)
Bibliografická identifikace v angličtině Author's first name and surname: Lenka Boťchová, BA Title of the master thesis: Does status epilepticus during early postnatal period influence laboratory rat psychomotor development? Department: Department of Rehabilitation and Exercise Medicine Supervisor: doc. PharmDr. H. Kubová, DrSc. The year of presentation: 2013 Abstract: The purpose of this study is to evaluate the influence of status epilepticus (SE) in postnatal development early phase on laboratory rat psychomotor development. Experimentally caused (SE) is the most common mode of epileptogenesis, which is the process leading to the epilepsy creation, and typical comorbidities. The influence of the early SE was studied when using lithium/pilocarpine model of SE induced on 12 days old rat cubs, which were repeatedly exposed to the "open field" test until 32nd day of their lives that means until the puberty beginning. The evaluation is focused on cognition and overall locomotion changes and anxiety demonstrations. The results show that in short periods after SE (up to 1 month) the cognitive functions regarding the habituation disorder are not worsened. However, hyperactivity short-term disposition and worse adaptability to experimental conditions due to animal anxiety increase were detected. Motor skills of...
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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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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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