scispace - formally typeset
Open AccessJournal ArticleDOI

Rapid Ca2+ channel accumulation contributes to cAMP-mediated increase in transmission at hippocampal mossy fiber synapses

TLDR
In this article, paired pre-and postsynaptic recordings from hippocampal mossy fiber-CA3 synapses were used to reveal the underlying mechanisms for the cyclic adenosine monophosphate (cAMP)-dependent potentiation of neurotransmitter release.
Abstract
The cyclic adenosine monophosphate (cAMP)-dependent potentiation of neurotransmitter release is important for higher brain functions such as learning and memory. To reveal the underlying mechanisms, we applied paired pre- and postsynaptic recordings from hippocampal mossy fiber-CA3 synapses. Ca2+ uncaging experiments did not reveal changes in the intracellular Ca2+ sensitivity for transmitter release by cAMP, but suggested an increase in the local Ca2+ concentration at the release site, which was much lower than that of other synapses before potentiation. Total internal reflection fluorescence (TIRF) microscopy indicated a clear increase in the local Ca2+ concentration at the release site within 5 to 10 min, suggesting that the increase in local Ca2+ is explained by the simple mechanism of rapid Ca2+ channel accumulation. Consistently, two-dimensional time-gated stimulated emission depletion microscopy (gSTED) microscopy showed an increase in the P/Q-type Ca2+ channel cluster size near the release sites. Taken together, this study suggests a potential mechanism for the cAMP-dependent increase in transmission at hippocampal mossy fiber-CA3 synapses, namely an accumulation of active zone Ca2+ channels.

read more

Citations
More filters
Journal ArticleDOI

Calcium dependence of neurotransmitter release at a high fidelity synapse.

TL;DR: In this article, the authors investigated the Ca2+-sensitivity of vesicle priming, fusion, and replenishment at mossy fiber synapses in the rodent cerebellum.
Journal ArticleDOI

Prolonged development of long-term potentiation at lateral entorhinal cortex synapses onto adult-born neurons.

TL;DR: For example, the authors found that adult-born neurons did not undergo significant LTP at LPP synapses, and often displayed long-term depression after theta burst stimulation.
Journal ArticleDOI

Mechanisms of Synaptic Vesicle Exo- and Endocytosis

TL;DR: The contribution of active zone proteins to presynaptic plasticity and to homeostatic readjustment during and after intense activity, in addition to activity-dependent endocytosis are discussed.
Journal ArticleDOI

Increased vesicle fusion competence underlies long-term potentiation at hippocampal mossy fiber synapses

TL;DR: In this article , the authors induced long-term potentiation (LTP) by optogenetic tools and applied direct presynaptic patch-clamp recordings and found that the action potential waveform and evoked Ca2+ currents remained unchanged after LTP induction.
References
More filters
Journal ArticleDOI

Short-Term Synaptic Plasticity

TL;DR: The evidence for this hypothesis, and the origins of the different kinetic phases of synaptic enhancement, as well as the interpretation of statistical changes in transmitter release and roles played by other factors such as alterations in presynaptic Ca(2+) influx or postsynaptic levels of [Ca(2+)]i are discussed.
Journal ArticleDOI

The Molecular Biology of Memory Storage: A Dialogue Between Genes and Synapses

TL;DR: This book aims to investigate elementary forms of learning and memory at a cellular molecular level—as specific molecular activities within identified nerve cells withinidentified nerve cells.
Journal ArticleDOI

Mushroom body memoir: From maps to models

TL;DR: Genetic intervention in the fly Drosophila melanogaster has provided strong evidence that the mushroom bodies of the insect brain act as the seat of a memory trace for odours, and the development of a circuit model that addresses this function might allow the mushrooms to throw light on the basic operating principles of the brain.
Journal ArticleDOI

Multiple roles of calcium ions in the regulation of neurotransmitter release.

TL;DR: Two distinct roles of [Ca(2+)] are proposed in vesicle recruitment: one accelerating "molecular priming" (vesicle docking and the buildup of a release machinery), the other promoting the tight coupling between releasable vesicles and Ca(2+) channels.
Journal ArticleDOI

Intracellular calcium dependence of transmitter release rates at a fast central synapse

TL;DR: Kinetic analysis of transmitter release rates after [Ca2+]i steps revealed the rate constants for calcium binding and vesicle fusion, and transient elevations to only 10 µM induce fast transmitter release, which depletes around 80% of a pool of available vesicles in less than 3 ms.
Related Papers (5)