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Optical Signals of Brain
Konopková, Renata ; Otáhal, Jakub (advisor) ; Kittnar, Otomar (referee) ; Valeš, Karel (referee)
Intrinsic optical signals are the signals reflecting changes in transmittance or reflectance of the light illumitating the tissue. Registration of such changes can be applied for the detection of physiological condition in the slices of biological tissues (in vitro) or in the whole animal (in vivo). The aim of this project is to introduce this topic and show different possibilities for the detection of changing optical properties of nervous tissue both in vitro and in vivo. The detection system of both light source and attachment of the optical fibre to the skull of the animal for in vivo experimets have been designed. The proper experimental part of the study have been done in hippocampal tissue slices and shows the correlation of the tissue activity and the optical signal at level of ion channels, glutamatergic synaptic activity, glial component of the signal and mitochondrial signal. We are dealing with the source of the noice that we record while detecting rather subtle changes of optical properties. We are indroducing the software VisionBrain for synchronous detection of both electrical and optical changes. Keywords: Intrinsic optical signals, hippocampus, imaging, biomechanics
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Damage to oligodendrocytes and axons following endothelin 1 - induced focal cerebral ischemia
Brožíčková, Carole ; Otáhal, Jakub (advisor) ; Konopková, Renata (referee)
Aims: The purpose of this study was to characterize the regional patterns of neuronal and axonal injury in immature rats following FCI. Methods: Experiments were performed in Wistar rats on postnatal day 12 and 25. FCI was induced by the intracerebral injection of Endothelin 1 (ET-1). Neuronal and axonal injury was assessed by the means of qualitative morphologic methods. Results: Our findings demonstrate that ET-1 induced FCI in the developing rat brain generates neuronal injury in the ipsilateral cortex and a distinct pattern of subcortical neuronal injury. The spatial spread of the damage to myelinated fibers seemed to be bigger than the extent of the area, where degenerating neurons were observed. Keywords: Oligodendrocyte, Focal cerebral ischemia, Endothelin-1, Myelin
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Anterograde tracing - a method for detection of plasticity of neuronal tracts
Krausová, Zuzana ; Otáhal, Jakub (advisor) ; Konopková, Renata (referee)
Title of work: Anterograde tracing - method for detecting conversion neuronal pathways in CNS focal lesion Objective: Create a suitable methodology for dyeing commissural fibers and its future use it to evaluate the plasticity of nerve tissue and confirmed using the anterograde tracer detecting fibers from the application site of the tracer in the contralateral projection area. Method: The experiment was carried out on adult individuals of the rat, which It was applied anterograde tracer BDA. Then we watched the ability of the tracer color commissural nerve fibers and fibers on the behavior of the application site in sensorimotor cortex. Results show that Biotinylated dextran amine is capable as anterograde tracer color neurons and fibers in the puncture cannula. However, our experiment It proves that BDA is suitable for marking commissural connections from the application site contralateral. Key words: focal cerebral ischemia, anterograde tracing, BDA, white matter, plasticity nervous tissue Powered by TCPDF (www.tcpdf.org)
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Detection of neuronal pathways after CNS lesions by using dextran amine.
Muchová, Zuzana ; Konopková, Renata (referee) ; Otáhal, Jakub (advisor)
Title of work: Detection of neuronal pathways after CNS lesions by using dextran amine. Aim: Develop a metodology for pathway tracing with the substance transmitted by axonal anterograde transport and compare iontophoretic and pressure injection of BDA. Methods: The experiment was performed on adult rats which where injected iontophoretic and pressure anterograde tracer BDA. One week after injection were decapitated in deep anesthesia, their brains removed, frozen in dry ice and stored at -70řC. The brains were then cut into thin coronal slice (50 µm), immunolabeled and loaded on microscopic slides. Individual sections were examined labeling nerve fibers at the injection site, its surroundings and contralateral side of the hemisphere. Results: After injections of anterograde tracer BDA into the nervous tissue have been shown labeling of nerve fibers at the injection site, surroundings and contralateral side of the hemisphere. As an efficient method for its injection was determined according to results of the pressure method. Key words: anterograde tracer, BDA, iontophoretic injection, cerebral ischemia, neuroplasticity
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Electrophysiological Models of Seizure like Activity for NO Detection in Vitro
Novák, Karel ; Konopková, Renata (referee) ; Otáhal, Jakub (advisor)
Definition of work: Electrophysiological models of seizure like activity for NO detection in vitro Supervisor: MUDr. Jakub Otáhal, PhD. Department of Anatomy and Biomechanics FTVS CUNI Department of Developmental Epileptology CAS, Institute of Physiology Consultant: Mgr. Renata Konopková Department of Developmental Epileptology CAS, Institute of Physiology Aim: The aim of the thesis is to introduce nitric oxide (NO) and its role in physiology and pathophysiolgy of central nervous system (CNS), with the intention of epileptiform activity in the nervous tissue. Our research was realized on rat hippocampal slices in vitro and it compares the experimental biochemical models (low-Mg2+ , high-K+ , Carbachol, Bicuculline and 4-Aminopyridine model). These changes in the environment of slice should evoke the epileptiform activity in the nervous tissue of the rat. The final aim of the thesis is to create an experimental model of epileptiform activity in vitro in our setup for imaging techniques and NO detection. Methods: Experiments were performed in rat hippocampal slices in vitro. Rats were deeply anaesthetized with ether and decapitated. Brain was rapidly removed from the scull, cut in oxygenated (95%) and cooled (0, 5 řC) artificial cerebrospinal fluid (ACSF) using vibratome in coronal slices of 400µm of...
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Method for assesment of the effect of selected anesthetics on H-reflex in laboratory rat.
Komárková, Mariana ; Otáhal, Jakub (advisor) ; Konopková, Renata (referee)
Title of work: Method for Assesment of the Effect of Selected Anesthetics on H-reflex in Laboratory Rat Objective: To create an applicable method for recording of the H-reflex of freely moveable unanesthetized rats. Methods: Three adult rats were each implanted in the right leg with stimulating electrodes in a flexible cuff on the tibial nerve and a pair of recording electrodes in the triceps surae muscle. After recovering it was evaluated if the electrodes are appropriate for stimulation of peripheral nerve and for recording of ongoing EMG and evoked EMG (H-reflex, M- response). Results: It is possible to use stimulating electrodes in a flexible cuff and a pair of recording electrodes for recording ongoing EMG and evoked EMG (H-reflex, M-response) in freely moveable rats. The experiment did not determine which kind of metal is the most appropriate for conductor for recording high quality EMG. Keywords: H-reflex, Electromyography, Implanted electrodes, Rat, Electrophysiology
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The Occurence of Muscle Activity in Correlation with the EEG Recording of Developmentally Different Groups of Rats
Feštrová, Veronika ; Otáhal, Jakub (advisor) ; Konopková, Renata (referee)
Objective: The aim of this thesis is to determine both the number and incidence of muscle twitches muscle activity in individual groups of pups in rats, possibly record the simultaneous occurrence of EEG activity, which points to the involvement of cortical levels of motor control. Method: The experiment was conducted on 4 groups of pups in rats, divided according to age, which was performed by the EMG electrodes into the extracellular space neck muscles and electrodes 6 - 4 sensor, reference and ground epidural placed for EEG activity. Have also been reported already mentioned curves and captured video footage necessary for final processing and analysis. Results: After statistical evaluation of experimental data has been demonstrated numerous of muscle jerks with developmentally youngest experimental group P7 and occurrence locomotor activity in developmentally older groups correlated with increased activation in cerebral cortex, which was confirmed by increased levels of energy and entropy of the EEG signal. These values also increased with increasing age, as evidenced by the gradual maturation of cortical motor control. Keywords: motor ontogenesis, surface electromyography, electroencephalography, descending path, rat, clonus Powered by TCPDF (www.tcpdf.org)
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The Role of Furosemide on Intrinsic Optical Signals in Hippocampal slices
Kuta, Igor ; Konopková, Renata (referee) ; Otáhal, Jakub (advisor)
Title of work: The Role of Furosemide on Intrinsic Optical Signals in hippocampal slices Objective: Learn how furosemide affects the internal optical signals in the rat hippocampus. Method: Measurement of IOS on slices of hippocampus in electro DG. detection IOS changes in the application of furosemide. Results: Internal optical signals are dependent on the activation of tissues and exhibit regional differences in hippocampal different layers. The concentration furosemide increases optical response of a tissue. Conclusion: The physiological processes in the nervous tissue are associated with changes in their optical properties. Furosemide in our work increased intrinsic optical signals. The change was more pronounced in dendritic compared with CA3 pyramidal layer. Keywords: hippocampus, an inner optical signals, furosemide, neuroglia, light transmission Powered by TCPDF (www.tcpdf.org)
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Damage of Neurons, Blood-brain Barrier and Folowing Immune Reaction During Ischemic Stroke After Endothelin-1 Application
Lutovská, Jana ; Otáhal, Jakub (advisor) ; Konopková, Renata (referee)
Work objectives: The aim of this diploma work was taking up with microscopic identification metods of particular cell types of CNS, detection of blood-brain-barrier permeability and "dying" neurons. We are interested how the cellulate elements - neurons and astrocyte - are affected by cerebral ischemia and if the permeability of the blood-brain barrier is disrupted. Methodology: Experiments were performed in Wistar rats on postnatal day 12 or 25 (17 together). Cannula for vasoconstrictor Endothelin-1 infusion was inserted into left hemisphere to induce focal cerebral ischemia. Animals were let to live for 24 hours and then all rats were deeply anesthetized with urethane injection. The brains were sectioned in the coronal plane 50m thick. Adjacent series of sections were processed for Fluoro- Jade B to detect degenerating neurons, blood-brain barrier disruption was investigated using Evans Blue dye. Immunohistochemical labeling was used for IgG and visualization of hypertrofic astrocytes by GFAP. Common observation of brain was preformed under upride microscope with fluorescence. Results: Our findings demonstrate that focal cerebral ischemia generates induced by ET-1 into cerebral tissue damage. Degenerating neurons were observed in affected areas. Blood-brain barrier is disturbed in the same area as...
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Influence of temperature and stimulus intensity on FAD transience in rat hippocampal slices in vitro
Rous, Matouš ; Otáhal, Jakub (advisor) ; Konopková, Renata (referee)
Aims: The purpose of this study was to characterize the influence of temperature and stimulus intensity on flavoprotein autofluorescence in rat hippocampal slices. Methods: Experiments were performed in hippocampal slices of adult male Wistar rats. Slices of 400 µm of thickness were maintained in submerged recording chamber, through which oxygenated ACSF was perfused (2 ml/min). Synaptic activation was being made by bipolar stimulating electrode (10s stimulus train 20Hz) placed in hillus of the dentate gyrus (Mossy fibers). FAD signals were detected by cooled 12-bit CCD-camera (RETIGA2000R). Results: Our findings demonstrate that FAD autofluorescence signals were significantly decreased at higher temperature. The data confirmed that FAD autofluorescence signals showed smaller light intensity in different layers of CA3 under the same conditions at 36řC compared to 26řC. Our data approved that under defined conditions FAD fluorescence signals have risen during stimulation. Keywords: Mitochondria, FAD autofluorescence, temperature, stimulus intensity, hippocampus, rat.
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