Aims: Patterns of synaptic activity determine synaptic strengthening or weakening that is typically represented as long-term potentiation (LTP) and long-term depression (LTD), respectively. In the present study, we aim to test whether a conditioning stimulation of the spinal trigeminal subnucleus caudalis (Vc) induces LTP at excitatory synapses in the subnucleus interpolaris (Vi) and to characterize the LTP.
Main Methods: Generally, a presynaptic high-frequency stimulation (HFS) protocol can induce LTP at excitatory synapses in the brain, including the spinal cord. Therefore, LTP in the Vi was induced by the HFS (3 tetani at 100 Hz) of Vc in the horizontal brainstem slices. By pretreating slices with antagonists for NMDA receptors, metabotropic glutamate receptor subtype 1 or 5 (mGluR1 or 5), GABAA receptors, glycine receptors and Ca(2+) chelator, the LTP was characterized.
Key Findings: The HFS reliably but slowly induced LTP of excitatory synaptic transmission in the Vi. This LTP was not dependent on NMDA receptor activation; however, it did require the activation of mGluR1, but not mGluR5, and an intracellular Ca(2+) rise. Interestingly, this LTP induction required inhibitory synaptic transmission mediated by GABAA and glycine receptors, and coincided with the slow development of LTD at GABAergic synapses. The GABAergic LTD was mediated by mGluR1 and the intracellular Ca(2+) rise.
Significance: These data suggest that the modulation of GABAergic synaptic transmission by conditioning synaptic activity contributes to the induction and expression of LTP at excitatory synapses in the Vi.
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http://dx.doi.org/10.1016/j.lfs.2015.11.024 | DOI Listing |
Sci Rep
January 2025
Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, 04510, Mexico City, Mexico.
Autism spectrum disorder (ASD) comprises alterations in brain anatomy and physiology that ultimately affect information processing and behavior. In most cases, autism is considered idiopathic, involving alterations in numerous genes whose functions are not extensively documented. We evaluated the C58/J mouse strain as an idiopathic model of ASD, emphasizing synaptic transmission as the basis of information processing.
View Article and Find Full Text PDFVision Res
January 2025
Centre for Brain and Behaviour, School of Biological and Behavioural Sciences, Queen Mary University of London, London E1 4NS, UK.
The traditional understanding of brain function has predominantly focused on chemical and electrical processes. However, new research in fruit fly (Drosophila) binocular vision reveals ultrafast photomechanical photoreceptor movements significantly enhance information processing, thereby impacting a fly's perception of its environment and behaviour. The coding advantages resulting from these mechanical processes suggest that similar physical motion-based coding strategies may affect neural communication ubiquitously.
View Article and Find Full Text PDFTrends Biochem Sci
January 2025
Research Group Neuroplasticity, Leibniz Institute for Neurobiology, Magdeburg, Germany; Leibniz Group 'Dendritic Organelles and Synaptic Function', Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; Center for Behavioral Brain Sciences, Otto von Guericke University, Magdeburg, Germany; German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany. Electronic address:
The brain is an exceptionally lipid-rich organ with a very complex lipid composition. Lipids are central in several neuronal processes, including membrane formation and fusion, myelin packing, and lipid-mediated signal transmission. Lipid diversity is associated with the evolution of higher cognitive abilities in primates, is affected by neuronal activity, and is instrumental for synaptic plasticity, illustrating that lipids are not static components of synaptic membranes.
View Article and Find Full Text PDFJ Neurosci
January 2025
Institute of Neuroimmunology, Slovak Academy of Science, 84510 Bratislava, Slovakia.
Extracellular matrix (ECM) is a network of macromolecules which has two forms - perineuronal nets (PNNs) and a diffuse ECM (dECM) - both influence brain development, synapse formation, neuroplasticity, CNS injury and progression of neurodegenerative diseases. ECM remodeling can influence extrasynaptic transmission, mediated by diffusion of neuroactive substances in the extracellular space (ECS). In this study we analyzed how disrupted PNNs and dECM influence brain diffusibility.
View Article and Find Full Text PDFAlzheimers Dement
December 2024
Division of Neurogeriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society (NVS), Karolinska Institutet, Stockholm, Sweden.
Background: Alzheimer's disease (AD) is associated with synaptic and memory dysfunction. A pathological hallmark of the disease is reactive astrogliosis, with reactive astrocytes surrounding amyloid plaques in the brain. Astrocytes have also been shown to be actively involved in disease progression, nevertheless, mechanistic information about their role in synaptic transmission during AD pathology is lacking.
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