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The Role of Aquaporin 4 channels and Transient Receptor Potential Vanilloid 4 channels in astrocytic swelling
Heřmanová, Zuzana ; Anděrová, Miroslava (advisor) ; Machová Urdzíková, Lucia (referee)
Astrocytes posses a wide range of functions within the brain. In response to ischemic conditions they swell due to increased uptake of osmolytes and they are mainly responsible for cytotoxic edema formation. However, they are also able to regulate their volume by releasing osmolytes together with water via the process of regulatory volume decrease (RVD). The Aquaporin 4 (AQP4) channel and Transient receptor potential vanilloid 4 (TRPV4) channel are suspected to be strongly involved in these processes of astrocytic volume regulation. The goal of the present diploma thesis was to clarify the role of both channels in astrocytic swelling in situ. For our experiments we used a subpopulation of green fluorescent protein-labelled astrocytes from AQP4-deficient (AQP4-/- ), TRPV4-deficient (TRPV4-/- ) and control (Ctrl) mice. Cell volume alterations were induced in acute brain slices by hypoosmotic stress or by oxygen-glucose deprivation (OGD). Data were quantified using fluorescence intensity-based approach in the whole cells and in astrocytic endfeet. Our results indicate, that there is no difference in astrocytic swelling or cell volume recovery between astrocytes from AQP4-/- , TRPV4-/- and control mice when exposed to hypoosmotic stress. On the contrary, volume changes induced by OGD varied...
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The role of astrocytes in the formation of brain edema
Heřmanová, Zuzana ; Anděrová, Miroslava (advisor) ; Pačesová, Dominika (referee)
Brain edema is a cause of mortality accompanying number of pathologies such as ischemia, traumatic brain injury, tumors or liver and kidney failure. It is described as a process of osmotic and water flux alterations, which lead to cell volume changes and to an increase in intracranial pressure. Brain edema is usually classified into two types: vasogenic and cytotoxic. Development of vasogenic edema is connected to the blood brain barrier disruption. Water accumulates in the extracellular space and exerts pressure on the cellular compartments of the tissue. The cytotoxic type of edema is characterized by water accumulation within the cells. The process of cellular volume enlargement is termed cellular swelling. Cytotoxic swelling is usually connected to glial cells, namely astrocytes, as these cells represent a part of the blood brain barrier and thus they influence homeostasis inside the brain. Water flows across cytoplasmic membrane through a system of specialized channels - aquaporins. For the brain edema formation, aquaporin 4 is the most important. It is localized on astrocytic membranes and using aquaporin-null mice, it has been shown, that it participates in water clearance in physiological and pathological conditions. Since the water fluxes are passive, the driving force for edema formation...
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The role of AQP4 and TRPV4 channels in the ischemic brain edema: focusing on glial cells
Kročianová, Daniela ; Anděrová, Miroslava (advisor) ; Máčiková, Lucie (referee)
Cerebral ischemia, also known as stroke, is one of the most common causes of death. It is accompanied by the formation of edema, which can be characterized as an influx of water and osmolytes into the brain, causing volume alterations. We recognize two types of cerebral edema - vasogenic, characterized by the disruption of the blood-brain barrier (BBB) and increase of the extracellular volume, and cytotoxic, caused by the increase of the volume of cells, mainly glia. The major contributors to the formation of cytotoxic edema are the astrocytes, which, in physiological conditions, are responsible for the maintenance of the BBB and keeping the homeostasis of the brain and spinal cord or central nervous system. The mechanism responsible for the process of volume and osmotic changes are the transmembrane channels, mainly aquaporin 4 (AQP4) and transient receptor potential vanilloid 4 (TRPV4). AQP4 is the main pathway for water influx as well as efflux when the edema subsides. TRPV4 is likely responsible for the maintenance of the osmotic balance of the organism, although its precise role in the formation of the edema has not yet been fully elucidated. The main aim of this thesis was to categorize the types of cerebral ischemia and edema, and to describe the process of cerebral edema formation and the...
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The role of AQP4 and TRVP4 channels in the ischemic brain edema: focusing on glial cells.
Kročianová, Daniela ; Anděrová, Miroslava (advisor) ; Máčiková, Lucie (referee)
Cerebral ischemia, also known as stroke, is one of the most common causes of death. It is accompanied by the formation of edema, which can be characterized as an influx of water and osmolytes into the brain, causing volume alterations. We recognize two types of cerebral edema - vasogenic, characterized by the disruption of the blood-brain barrier (BBB) and increase of the extracellular volume, and cytotoxic, caused by the increase of the volume of cells, mainly glia. The major contributors to the formation of cytotoxic edema are the astrocytes, which, in physiological conditions, are responsible for the maintenance of the BBB and keeping the homeostasis of the brain and spinal cord or central nervous system. The mechanism responsible for the process of volume and osmotic changes are the transmembrane channels, mainly aquaporin 4 (AQP4) and transient receptor potential vanilloid 4 (TRPV4). AQP4 is the main pathway for water influx as well as efflux when the edema subsides. TRPV4 is likely responsible for the maintenance of the osmotic balance of the organism, although its precise role in the formation of the edema has not yet been fully elucidated. The main aim of this thesis was to categorize the types of cerebral ischemia and edema, and to describe the process of cerebral edema formation and the...
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The Role of Aquaporin 4 channels and Transient Receptor Potential Vanilloid 4 channels in astrocytic swelling
Heřmanová, Zuzana ; Anděrová, Miroslava (advisor) ; Machová Urdzíková, Lucia (referee)
Astrocytes posses a wide range of functions within the brain. In response to ischemic conditions they swell due to increased uptake of osmolytes and they are mainly responsible for cytotoxic edema formation. However, they are also able to regulate their volume by releasing osmolytes together with water via the process of regulatory volume decrease (RVD). The Aquaporin 4 (AQP4) channel and Transient receptor potential vanilloid 4 (TRPV4) channel are suspected to be strongly involved in these processes of astrocytic volume regulation. The goal of the present diploma thesis was to clarify the role of both channels in astrocytic swelling in situ. For our experiments we used a subpopulation of green fluorescent protein-labelled astrocytes from AQP4-deficient (AQP4-/- ), TRPV4-deficient (TRPV4-/- ) and control (Ctrl) mice. Cell volume alterations were induced in acute brain slices by hypoosmotic stress or by oxygen-glucose deprivation (OGD). Data were quantified using fluorescence intensity-based approach in the whole cells and in astrocytic endfeet. Our results indicate, that there is no difference in astrocytic swelling or cell volume recovery between astrocytes from AQP4-/- , TRPV4-/- and control mice when exposed to hypoosmotic stress. On the contrary, volume changes induced by OGD varied...
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The role of astrocytes in the formation of brain edema
Heřmanová, Zuzana ; Anděrová, Miroslava (advisor) ; Pačesová, Dominika (referee)
Brain edema is a cause of mortality accompanying number of pathologies such as ischemia, traumatic brain injury, tumors or liver and kidney failure. It is described as a process of osmotic and water flux alterations, which lead to cell volume changes and to an increase in intracranial pressure. Brain edema is usually classified into two types: vasogenic and cytotoxic. Development of vasogenic edema is connected to the blood brain barrier disruption. Water accumulates in the extracellular space and exerts pressure on the cellular compartments of the tissue. The cytotoxic type of edema is characterized by water accumulation within the cells. The process of cellular volume enlargement is termed cellular swelling. Cytotoxic swelling is usually connected to glial cells, namely astrocytes, as these cells represent a part of the blood brain barrier and thus they influence homeostasis inside the brain. Water flows across cytoplasmic membrane through a system of specialized channels - aquaporins. For the brain edema formation, aquaporin 4 is the most important. It is localized on astrocytic membranes and using aquaporin-null mice, it has been shown, that it participates in water clearance in physiological and pathological conditions. Since the water fluxes are passive, the driving force for edema formation...
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The importance of the Rhine-Main-Danube Canal for Central European logistics area
Kapustová, Alena ; Sato, Alexej (advisor) ; Hinčica, Vít (referee)
This bachelor thesis executes an utilization and importance of the Rhine-Mohan-Danube Canal as a major waterway in Europe. One of the main goals, with using the available information, is to confirm or disconfirm, on the basis of the hypothesis, whether the Rhine-Main-Danube can meet the requirements, for that was originally built. The introduction of the main text introduces inland waterway transport and evaluates its effectiveness. Later is presented the Rhine-Main-Danube canal and analysis of its transport efficiency. Based on these data, it is possible to clarify the importance of the Rhine-Main-Danube Canal for countries in its availability. Individual parts of this waterway are providing information about the versatile use of watercourses. At the end of the main part are summarized the main advantages and disadvantages associated with using of the Rhine-Main-Danube Canal.
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The Commission for making the river Vltava and the river Labe in Bohemia navigable 1986 - 1931
Černá, Marcela ; Jakubec, Ivan (advisor) ; Hájek, Jan (referee)
The Commission for making the river Vltava and the river Labe in Bohemia navigable was founded in 1896 on the basis of a decree of the ministry of interior as the first water management office to be systematically engaged in making Czech rivers navigable by the canalization method. The Commission was headed by the vice-regent of the Kingdom of Bohemia to whom the members of state's and country's curia were subordinate. The executive section was represented by the central office, composed of the technical and administrative departments. Its activities were financed by two thirds by the Austrian state, one third was paid from the Czech country's treasury. After the establishment of the independent Czechoslovak republic, both curias were dissolved and the Commission was put under the control of the ministry of public works. The president of the country's political administration was appointed as the head of the Commission. The competence of the Commission was step by step extended from the initially entrusted task of making the river Vltava and the river Labe in the division Prague - Ústí nad Labem navigable also to making the river Vltava in Prague navigable as well as to the adaptation of the Holešovice port in Prague to a modern trade port and to drawing up studies on the utilization of water...
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