A5065316867- Neuroscience and Neuropharmacology Research
- Neural dynamics and brain function
- Photoreceptor and optogenetics research
- Neuroscience and Neural Engineering
- Memory and Neural Mechanisms
- Advanced Fluorescence Microscopy Techniques
- Ion channel regulation and function
- Retinal Development and Disorders
- Receptor Mechanisms and Signaling
- Optical Imaging and Spectroscopy Techniques
- Advanced Memory and Neural Computing
- Biochemical effects in animals
- Neuroendocrine regulation and behavior
- Visual perception and processing mechanisms
- Neuroinflammation and Neurodegeneration Mechanisms
- Heme Oxygenase-1 and Carbon Monoxide
- Intracranial Aneurysms: Treatment and Complications
- Glaucoma and retinal disorders
- Traumatic Brain Injury and Neurovascular Disturbances
- Photochromic and Fluorescence Chemistry
- Functional Brain Connectivity Studies
- Nicotinic Acetylcholine Receptors Study
- Neurogenesis and neuroplasticity mechanisms
- Retinal Imaging and Analysis
- Molecular Communication and Nanonetworks
Jena University Hospital
2014-2024
Friedrich Schiller University Jena
2007-2015
Klinik und Poliklinik für Neurologie
2007-2012
Center for Integrated Protein Science Munich
2010
Technical University of Munich
2006
Ludwig-Maximilians-Universität München
2002-2004
Columbia University
2000-2004
Heinrich Heine University Düsseldorf
1990-2000
Two-photon calcium imaging is a powerful means for monitoring the activity of distinct neurons in brain tissue vivo . In mammalian brain, such studies have been restricted largely to recordings from that were individually dye-loaded through microelectrodes. Previous attempts use membrane-permeant forms fluorometric indicators load populations yielded satisfactory results only cell cultures or slices immature tissue. Here we introduce versatile approach loading fluorescent indicator dyes...
A large body of evidence from in vitro studies suggests that GABA is depolarizing during early postnatal development. However, the mode action intact developing brain unknown. Here we examine vivo effects cells upper cortical plate using a combination electrophysiological and Ca(2+)-imaging techniques. We report at days (P) 3-4, depolarizes majority immature neurons occipital cortex anaesthetized mice. At same time, does not efficiently activate voltage-gated Ca(2+) channels fails to induce...
In the last decade, measurement of activity-dependent intrinsic optical signals (IOSs) in excitable tissues has become a useful tool for collecting data about spatial patterns information processing mammalian brain and spread excitation. Although extent IOS correlates well with electrical excitation, its time course is much slower, suggesting that it does not directly monitor activity. The aim this study was to investigate mechanisms responsible generation IOSs. Coronal neocortical slices...
Abstract Tactile sensation and vision are often both utilized for the exploration of objects that within reach though it is not known whether or how these two distinct sensory systems combine such information. Here in mice, we used a combination stereo photogrammetry 3D reconstruction whisker array, brain-wide anatomical tracing functional connectivity analysis to explore possibility tacto-visual convergence space circuitry primary visual cortex (VISp). Strikingly, find stimulation...
The brain contains an intrinsic vasopressin fiber system the function of which is unknown. It has been demonstrated recently that astrocytes express high levels a water channel, aquaporin-4 (AQP4). Because known to regulate aquaporin expression and translocation in kidney collecting ducts thereby control reabsorption, we hypothesized might serve similar brain. By recording optical signals acute cortical slice preparation showed evoked neuronal activity generates radial flux neocortex. rapid...
The functional role of the glial network as a draining system for extracellular potassium (spatial buffer) was investigated in rat neocortical brain slices. After electrical stimulation, space volume decreased middle cortical layers and increased upper layers, confirming predictions spatial buffer. widening associated with an increase potassium. data suggested delayed redistribution from to superficial layers. Interruption gap junctions abolished space. show that multicellular directed...
Axonally initiated action potentials back-propagate into spiny dendrites of central mammalian neurons and thereby regulate plasticity at excitatory synapses on individual spines as well linear supralinear integration synaptic inputs along dendritic branches. Thus, the electrical behaviour terminal branches is critical for integrative function nerve cells. The actual dynamics in branches, however, are not entirely clear, mostly because electrode recording from such small structures feasible....
Calcium imaging has been used as a promising technique to monitor the dynamic activity of neuronal populations. However, calcium trace is temporally smeared which restricts extraction quantities interest such spike trains individual neurons. To address this issue, reconstruction algorithms have introduced. One limitation reconstructions that underlying models are not informed about biophysics and burst generations. Such existing prior knowledge might be useful for constraining possible...
Synchronized activity is a universal characteristic of immature neural circuits that essential for their developmental refinement and strongly depends on GABAergic neurotransmission. A major subpopulation GABA-releasing interneurons (INs) expresses somatostatin (SOM) proved critical rhythm generation in adulthood. Here, we report mechanism whereby SOM INs promote neuronal synchrony the neonatal CA1 region. Combining imaging electrophysiological approaches, demonstrate pyramidal cells (PCs)...
Mammalian dendrites are active structures, capable of regenerative electrical activity. Dendritic spikes can mediate synaptic plasticity and could enrich the computational properties neurons. Besides sodium-based action potentials, which propagate throughout dendritic tree, neocortical pyramidal neurons also sustain that spatially restricted. The function these 'local' is unknown. We show local spikes, require activation N-methyl-d-aspartate receptors (NMDARs), induce long-term depression...
Abstract Background Optogenetic silencing techniques have expanded the causal understanding of functions diverse neuronal cell types in both healthy and diseased brain. A widely used inhibitory optogenetic actuator is e Np HR3.0, an improved version light-driven chloride pump halorhodopsin derived from Natronomonas pharaonis . major drawback HR3.0 related to its pronounced inactivation on a time-scale seconds, which renders it unsuited for applications that require long-lasting silencing....
Significance Neuronal circuits develop in an activity-dependent manner. In vitro data suggest that the intracellular accumulation of chloride—a universal characteristic immature nerve cells—drives network maturation through a depolarizing action neurotransmitter GABA. We here demonstrate deletion chloride cotransporter NKCC1 from forebrain pyramidal cells severely impairs hippocampal synchrony vitro. contrast, has weak and event type-dependent effects on spontaneous activity vivo, loss...
A large body of evidence suggests that the neurotransmitter GABA undergoes a developmental switch from being predominantly depolarizing-excitatory to hyperpolarizing-inhibitory. Recently published data, however, point possibility presumed depolarizing mode action during early development might represent an artifact due insufficient energy supply in vitro preparations used. Specifically, addition ketone dl-β-hydroxybutyrate (βHB) extracellular medium was shown prevent exerting excitatory...
Delayed cerebral vasospasm is the most common cause of mortality and severe neurological impairment in patients who survive subarachnoid hemorrhage. Despite improvements field diagnostic imaging, options for prevention medical treatment-primarily with calcium channel antagonist nimodipine or hemodynamic manipulations-are insufficient. Previous studies have suggested that heme bilirubin oxidation end products, originating from degraded hemoglobin around ruptured blood vessels, are involved...
Rationale: Delayed ischemic neurological deficit is the most common cause of impairment and unfavorable prognosis in patients with subarachnoid hemorrhage (SAH). Despite existence neuroimaging modalities that depict onset accompanying cerebral vasospasm, preventive therapeutic options are limited fail to improve outcome owing an insufficient pathomechanistic understanding delayed perfusion deficit. Previous studies have suggested BOXes (bilirubin oxidation end products), originating from...