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Influence of the epicardium on cardiac regeneration after cryoinjury during embryonic development - analysis of morphological and physiological changes
Neffeová, Kristýna ; Kolesová, Hana (advisor) ; Hovořáková, Mária (referee)
Millions of people die from myocardial infarction every year. In the heart, damaged cardiomyocytes do not regenerate and fibrotic scar forms. Surface layer of the heart - epicardium, improve heart regeneration processes by producing signalling factors. Epicardial cells undergo epithelial-mesenchymal transition and give rise to various cells involved in heart regeneration (coronary vessel formation and possibly new cardiomyocytes). To study the effect of epicardium on cardiac regeneration, I introduced a novel method of myocardial cryoinjury in avian embryos. In embryonic stages, where the heart is already covered by a layer of epicardium. Probe cooled in liquid nitrogen, injured the left ventricle of the heart and simulate myocardial infarction. Cryoinjury is an appropriate alternative to induce myocardial infarction as the coronary ligation is not feasible in early embryos. After cryoinjury, were observed changes in the epicardium. Epicardium is activated (expression of WT1) and detached from myocardium and form protrusions. In subepicardium we observed a large number of migrating cells. These cells undergo epithelial-mesenchymal transition were detected by cytokeratin and vimentin antibodies. We observed α-SMA positive cells and undifferentiated cardiomyocytes (N2.261 antibody) in the...
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Impact of early postnatal period on pro-arrhytmogenic substrate development caused by pressure overload in rat heart
Zábrodská, Eva ; Olejníčková, Veronika (advisor) ; Kolesová, Hana (referee)
In adult heart, pressure overload leads to cardiac hypertrophy. Higher propensity of hypertrophied myocardium to life-threatening arrhythmia is attributed to structural, mechanical and electrical remodeling. Pro-arrhythmogenic remodeling comprise several factors depending on an experimental model and a stage of heart failure. This thesis aims to characterize the impact of these factors in our unique model of pressure overloaded neonatal rat heart. The constriction of abdominal aorta was performed at postnatal day 2 in male Wistar rats. Decreased body weight, significant since week 6, was observed during development of cardiomegaly. At 12 weeks, the heart to body weight ratio was increased by 45 % and by 109 % in group with compensated (AC I) and decompensated (AC II) heart failure, respectively. At this age, the ECG was recorded and histological and immunohistochemical measurements were performed to analyze the pro-arrhythmogenic remodeling of working myocardium and cardiac conduction system. The markers of pro-arrhytmogenic remodeling such as significant prolongation of QT and QTc intervals were observed in the ECG recordings of AC II animals. However, spontaneously occurring arrhythmias was not detected. Further analysis of working myocardium showed decrease in Cx43 expression and its...
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Molecular mechanisms of coronary vasculature development
Neffeová, Kristýna ; Kolesová, Hana (advisor) ; Neckář, Jan (referee)
The cardiovascular system is the first functional system that develops in vertebrates during embryonic development. Its irreplaceable function is the transport of nutrients and the removal of waste products. During the development the heart not only grows, but also acts as a pump that drives the blood circulation of the embryo. With advancing development, it is necessary to ensure an adequate supply of oxygen to the heart, for that reason coronary arteries are formed. Each cardiomyocyte is surrounded by at least one capillary, therefore the interaction between cardiomyocytes and endothelial cells plays an indispensable role in the proper functioning of the heart. Understanding, how cardiomyocytes and endothelial cells communicate, is essential for medical research in cardiac tissue regeneration. A number of factors involved in coronary development are described in the literature. However, these factors are described as separate signaling pathways, not as a system of mutually interacting mechanisms. The main goal of my bachelor thesis is to connect individual signaling cascades important in cardiomyocyte-endothelial cell communication and describe their interactions. The main factors overviewed are VEGF, Notch, PDGF, Angiopoietin and others. Factors function and signalization is reviewed in details....
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Mechanisms of blood vessels development in the branchial archem region
Kolesová, Hana
Mechanisms of blood vessels development in the branchial archem region Thesis - Mgr. Hana Kolesová Supervisor: Prof. MUDr. Miloš Grim, DrSc. Institute of Anatomy, First Faculty of Medicine, Charles University, Prague Abstract Aortic arches development in the course of Pelobates fuscus metamorphosis Larval development of Spade-foot Toad Pelobates fuscus (Amphibia, Anura) is modified compared to tetrapod ancestors. However, it is still possible from its metamorphosis to reconstruct changes, which have occurred during the transition of vertebrates onto the dry land. Transformations of aortic arches during the metamorphosis have been studied by the corrosion casting of the vascular systém with Mercox. Corrosion casts were subsequently studied with a scanning electron microscope. Aim of this study is to compare development of aortic arches of Pelobates fuscus with other anuran species and contribute to the findings about the transformation of the aortic arches during the transition of the vertebrates onto the dry land. Aortic arches, which in larval period supply the gills, are considerably transformed due to the reduction of the gills and transition on the breathing of atmospheric oxygen. Aortic arches are in Pelobates suddenly transformed after a long period of gradual preparation and reduction of gill blood...
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název v anglickém jazyce není uveden
Kolesová, Hana ; Grim, Miloš (advisor) ; Slípka, Jaroslav (referee) ; Nečas, Emanuel (referee)
Branchial arches region and its blood vessels are extensively transformed in the embryonic development. Aim of this study is to investigate mechanisms of the branchial arches region development and to study how a morphogen Sonic hed gehog (Shh) participate on the formation and remodeling of branchial arches and their blood vessels. Influence of Shh was evaluated based on the changes caused by its inhibition in vivo. Shh function was inhibited with an anti-Shh antibody, which was produced into the embryo from the applied hybridoma cells. Shh signaling cascade was also inhibited by cyclopamine. Results show that Shh is important for dc novo format,ion of the blood vessels in the branchial arches region. Further Shh is necessary for stabilization of the vessel wall, mainly for anterior cardinal vein. Shh also alfects later vessel development and transformation, which includes i.e. fusion of the dorsal aorta, branching of the internal carotid artery and outflow tract development. Short time inhibition of Shh has minor effect on the apoptosis and proliferation activity of the branchial arches region mesenchymal cells. We assume that Shh signals directly to the blood vessels endothelial cells, as Shh receptor ptel is also expressed in endothelial cells and its signal is reduced with Shh inhibition. In studied...
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Mechanisms of blood vessels development in the branchial archem region
Kolesová, Hana
Mechanisms of blood vessels development in the branchial archem region Thesis - Mgr. Hana Kolesová Supervisor: Prof. MUDr. Miloš Grim, DrSc. Institute of Anatomy, First Faculty of Medicine, Charles University, Prague Abstract Aortic arches development in the course of Pelobates fuscus metamorphosis Larval development of Spade-foot Toad Pelobates fuscus (Amphibia, Anura) is modified compared to tetrapod ancestors. However, it is still possible from its metamorphosis to reconstruct changes, which have occurred during the transition of vertebrates onto the dry land. Transformations of aortic arches during the metamorphosis have been studied by the corrosion casting of the vascular systém with Mercox. Corrosion casts were subsequently studied with a scanning electron microscope. Aim of this study is to compare development of aortic arches of Pelobates fuscus with other anuran species and contribute to the findings about the transformation of the aortic arches during the transition of the vertebrates onto the dry land. Aortic arches, which in larval period supply the gills, are considerably transformed due to the reduction of the gills and transition on the breathing of atmospheric oxygen. Aortic arches are in Pelobates suddenly transformed after a long period of gradual preparation and reduction of gill blood...
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