Presynaptic glycine receptors on hippocampal mossy fibers.

Biochem Biophys Res Commun

Independent Hertie Research Group, Max-Planck Institute for Brain Research, D-60528 Frankfurt am Main, Germany.

Published: March 2010

Presynaptic glycine receptors (GlyRs) have been implicated in the regulation of glutamatergic synaptic transmission. Here, we characterized presynaptic GlyR-mediated currents by patch-clamp recording from mossy fiber boutons (MFBs) in rat hippocampal slices. In MFBs, focal puff-application of glycine-evoked chloride currents that were blocked by the GlyR antagonist strychnine. Their amplitudes declined substantially during postnatal development, from a mean conductance per MFB of approximately 600 pS in young to approximately 130 pS in adult animals. Single-channel analysis revealed multiple conductance states between approximately 20 and approximately 120 pS, consistent with expression of both homo- and hetero-oligomeric GlyRs. Accordingly, estimated GlyRs densities varied between 8-17 per young, and 1-3 per adult, MFB. Our results demonstrate that functional presynaptic GlyRs are present on hippocampal mossy fiber terminals and suggest a role of these receptors in the regulation of glutamate release during the development of the mossy fiber--CA3 synapse.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bbrc.2010.02.019DOI Listing

Publication Analysis

Top Keywords

presynaptic glycine
8
glycine receptors
8
hippocampal mossy
8
mossy fiber
8
presynaptic
4
receptors hippocampal
4
mossy
4
mossy fibers
4
fibers presynaptic
4
glyrs
4

Similar Publications

During neuronal synaptic transmission, the exocytotic release of neurotransmitters from synaptic vesicles in the presynaptic neuron evokes a change in conductance for one or more types of ligand-gated ion channels in the postsynaptic neuron. The standard method of investigation uses electrophysiological recordings of the postsynaptic response. However, electrophysiological recordings can directly quantify the presynaptic release of neurotransmitters with high temporal resolution by measuring the membrane capacitance before and after exocytosis, as fusion of the membrane of presynaptic vesicles with the plasma membrane increases the total capacitance.

View Article and Find Full Text PDF

The evolutionary transition from diffusion-mediated cell-cell communication to faster, targeted synaptic signaling in animal nervous systems is still unclear. Genome sequencing analyses have revealed a widespread distribution of synapse-related genes among early-diverging metazoans, but how synaptic machinery evolved remains largely unknown. Here, we examine the function of neurexins (Nrxns), a family of presynaptic cell adhesion molecules with critical roles in bilaterian chemical synapses, using the cnidarian model, Nematostella vectensis.

View Article and Find Full Text PDF

Role of palmitoylation on the neuronal glycine transporter GlyT2.

J Neurochem

September 2024

Departamento de Biología Molecular, Instituto de Biología Molecular (IUBM), Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Madrid, Spain.

The neuronal glycine transporter GlyT2 removes glycine from the synaptic cleft through active Na, Cl, and glycine cotransport contributing to the termination of the glycinergic signal as well as supplying substrate to the presynaptic terminal for the maintenance of the neurotransmitter content in synaptic vesicles. Patients with mutations in the human GlyT2 gene (SLC6A5), develop hyperekplexia or startle disease (OMIM 149400), characterized by hypertonia and exaggerated startle responses to trivial stimuli that may have lethal consequences in the neonates as a result of apnea episodes. Post-translational modifications in cysteine residues of GlyT2 are an aspect of structural interest we analyzed.

View Article and Find Full Text PDF

Neurexins play diverse functions as presynaptic organizers in various glutamatergic and GABAergic synapses. However, it remains unknown whether and how neurexins are involved in shaping functional properties of the glycinergic synapses, which mediate prominent inhibition in the brainstem and spinal cord. To address these issues, we examined the role of neurexins in a model glycinergic synapse between the principal neuron in the medial nucleus of the trapezoid body (MNTB) and the principal neuron in the lateral superior olive (LSO) in the auditory brainstem.

View Article and Find Full Text PDF

Purpose: The cystine/glutamate antiporter is involved in the export of intracellular glutamate in exchange for extracellular cystine. Glutamate is the main neurotransmitter in the retina and plays a key metabolic role as a major anaplerotic substrate in the tricarboxylic acid cycle to generate adenosine triphosphate (ATP). In addition, glutamate is also involved in the outer plexiform glutamate-glutamine cycle, which links photoreceptors and supporting Müller cells and assists in maintaining photoreceptor neurotransmitter supply.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!