A5035288029- Neuroscience and Neuropharmacology Research
- Connexins and lens biology
- Neuroinflammation and Neurodegeneration Mechanisms
- Barrier Structure and Function Studies
- Ion channel regulation and function
- Biochemical Analysis and Sensing Techniques
- Receptor Mechanisms and Signaling
- Hearing, Cochlea, Tinnitus, Genetics
- Neurogenesis and neuroplasticity mechanisms
- Alzheimer's disease research and treatments
- Mitochondrial Function and Pathology
- Ion Transport and Channel Regulation
- Biotin and Related Studies
- Cell Adhesion Molecules Research
- Drug Transport and Resistance Mechanisms
- Adipose Tissue and Metabolism
- Birth, Development, and Health
- Neonatal and fetal brain pathology
- Anesthesia and Neurotoxicity Research
- Nuclear Receptors and Signaling
- Toxin Mechanisms and Immunotoxins
- Calpain Protease Function and Regulation
Heinrich Heine University Düsseldorf
2007-2023
University of Kaiserslautern
2014-2020
Activation of glutamatergic synapses results in long-lasting sodium transients astrocytes mediated mainly by sodium-dependent glutamate uptake. Sodium elevations activate Na(+) /K(+) -ATPase and glucose uptake astrocytes, representing key signals for coupling glial metabolism to neuronal activity. Here, we analyzed the spread between hippocampal slice preparations. Stimulation a single astrocyte resulted an immediate elevation that neighboring within distance ∼ 100 μm. Amplitude, slope,...
The amyloid precursor protein (APP), a key player in Alzheimer's disease, belongs to the family of synaptic adhesion molecules (SAMs) due its impact on synapse formation and plasticity. These functions are mediated by both secreted APP ectodomain that acts as neurotrophic factor full-length forming trans-cellular dimers. Two homologs exist mammals: like proteins APLP1 APLP2, exhibiting partly overlap with those APP. Here we tested whether APLP2 also show features SAMs. We found all three...
Abstract Increased ammonium (NH 4 + ) concentration in the brain is prime candidate responsible for hepatic encephalopathy (HE), a serious neurological disorder caused by liver failure and characterized disturbed glutamatergic neurotransmission impaired glial function. We investigated mechanisms of NH ‐induced depolarization astrocytes mouse hippocampal slices using whole‐cell patch‐clamp potassium‐selective microelectrodes. At postnatal days (P) 18–21, perfusion with 5 mM evoked transient...
Astrocytic gap junctional coupling is a major element in neuron–glia interaction. There strong evidence that impaired involved neurological disorders. Reduced was, e.g., demonstrated for core regions of ischemic stroke suffer from massive cell death. In the surrounding penumbra, cells may recover, but recovery hampered by spreading depolarizations, which impose additional metabolic stress onto tissue. Spreading depolarizations are characterized transient breakdown cellular ion homeostasis,...
Neuronal inhibition is mediated by glycine and/or GABA. Inferior colliculus (IC) neurons receive glycinergic and GABAergic inputs, whereas in hippocampus (HC) predominantly relies on Astrocytes heterogeneously express neurotransmitter transporters are expected to adapt the local requirements regarding homeostasis. Here we analyzed expression of inhibitory IC HC astrocytes using whole-cell patch-clamp single-cell reverse transcription-PCR. We show that most both regions expressed functional...
Neurotransmitter clearance from the synaptic cleft is a major function of astrocytes and requires neurotransmitter transporters. In rodent lateral superior olive (LSO), conspicuous auditory brainstem center, both glycine GABA mediate inhibition. However, main inhibitory input medial nucleus trapezoid body (MNTB) appears to be glycinergic by postnatal day (P) 14, when circuit maturation almost accomplished. Using whole‐cell patch‐clamp recordings at P3‐20, we analyzed transporters (GlyT1)...
Astrocytes form large gap junctional networks that contribute to ion and neurotransmitter homeostasis. concentrate in the lateral superior olive (LSO), a prominent auditory brainstem center. Compared LSO, astrocyte density is lower region dorsal LSO (dLSO) internuclear space between paraolivary nucleus (SPN). We questioned whether exhibit certain properties reflect precise neuronal arrangement. Employing whole‐cell patch‐clamp concomitant injection of junction‐permeable tracer, we analyzed...
Malfunction of astrocytic K+ regulation contributes to the breakdown extracellular homeostasis during ischemia and spreading depolarization events. Studying astroglial changes is, however, hampered by a lack suitable techniques. Here, we combined results from fluorescence imaging, ion-selective microelectrodes, patch-clamp recordings in murine neocortical slices with calculation [K+]. Brief chemical caused reversible ATP reduction transient astrocytes. Moreover, [Na+] increased 24 mM...
Astrocytes and oligodendrocytes in different brain regions form panglial networks the topography of such can correlate with neuronal function. Astrocyte-oligodendrocyte lateral superior olive (LSO) – an auditory brainstem nucleus were found to be anisotropic a preferred orientation orthogonally tonotopic axis. We hypothesized that specialization might present other tonotopically organized nuclei, too. Thus, we analyzed gap junctional coupling center inferior colliculus (IC) another exhibits...
Anisotropy of tracer-coupled networks is a hallmark in many brain regions. In the past, topography these was analyzed using various approaches, which focused on different aspects, e.g., position, tracer signal, or direction coupled cells. Here, we developed vector-based method to analyze extent and preferential spreading. As model region, chose lateral superior olive—a nucleus that exhibits specialized network topography. acute slices, sulforhodamine 101-positive astrocytes were...
Anisotropic gap junctional coupling is a distinct feature of astrocytes in many brain regions. In the lateral superior olive (LSO), astrocytic networks are anisotropic and oriented orthogonally to tonotopic axis. CaV1.3 knock-out (KO) otoferlin KO mice, where auditory brainstem nuclei deprived from spontaneous cochlea-driven neuronal activity, circuitry disturbed. So far it was unknown if this disturbance also accompanied by an impaired topography LSO astrocyte networks. To answer question,...
Neurotransmitter homeostasis is important for proper synaptic signal transmission. Synaptically released neurotransmitters are recycled by direct reuptake into the presynaptic terminal and/or uptake perisynaptic astrocyte processes. In latter case, most metabolized and shuttled back to restore neurotransmitter content in that compartment. various regions of central nervous system (CNS), glycine GABA heterogeneously utilized inhibition neuronal activity – predominantly caudal regions, rostral...