Structural and functional plasticity of astrocyte processes and dendritic spine interactions

TY - JOUR

T1 - Structural and functional plasticity of astrocyte processes and dendritic spine interactions

AU - Perez-Alvarez, Alberto

AU - Navarrete, Marta

AU - Covelo, Ana

AU - Martin, Eduardo D

AU - Araque, Alfonso

N1 - alle EXTERNE sind INTERNE

PY - 2014/9/17

Y1 - 2014/9/17

N2 - Experience-dependent plasticity of synaptic transmission, which represents the cellular basis of learning, is accompanied by morphological changes in dendritic spines. Astrocytic processes are intimately associated with synapses, structurally enwrapping and functionally interacting with dendritic spines and synaptic terminals by responding to neurotransmitters and by releasing gliotransmitters that regulate synaptic function. While studies on structural synaptic plasticity have focused on neuronal elements, the structural-functional plasticity of astrocyte-neuron relationships remains poorly known. Here we show that stimuli inducing hippocampal synaptic LTP enhance the motility of synapse-associated astrocytic processes. This motility increase is relatively rapid, starting <5 min after the stimulus, and reaching a maximum in 20-30 min (t(1/2) = 10.7 min). It depends on presynaptic activity and requires G-protein-mediated Ca(2+) elevations in astrocytes. The structural remodeling is accompanied by changes in the ability of astrocytes to regulate synaptic transmission. Sensory stimuli that increase astrocyte Ca(2+) also induce similar plasticity in mouse somatosensory cortex in vivo. Therefore, structural relationships between astrocytic processes and dendritic spines undergo activity-dependent changes with metaplasticity consequences on synaptic regulation. These results reveal novel forms of synaptic plasticity based on structural-functional changes of astrocyte-neuron interactions.

AB - Experience-dependent plasticity of synaptic transmission, which represents the cellular basis of learning, is accompanied by morphological changes in dendritic spines. Astrocytic processes are intimately associated with synapses, structurally enwrapping and functionally interacting with dendritic spines and synaptic terminals by responding to neurotransmitters and by releasing gliotransmitters that regulate synaptic function. While studies on structural synaptic plasticity have focused on neuronal elements, the structural-functional plasticity of astrocyte-neuron relationships remains poorly known. Here we show that stimuli inducing hippocampal synaptic LTP enhance the motility of synapse-associated astrocytic processes. This motility increase is relatively rapid, starting <5 min after the stimulus, and reaching a maximum in 20-30 min (t(1/2) = 10.7 min). It depends on presynaptic activity and requires G-protein-mediated Ca(2+) elevations in astrocytes. The structural remodeling is accompanied by changes in the ability of astrocytes to regulate synaptic transmission. Sensory stimuli that increase astrocyte Ca(2+) also induce similar plasticity in mouse somatosensory cortex in vivo. Therefore, structural relationships between astrocytic processes and dendritic spines undergo activity-dependent changes with metaplasticity consequences on synaptic regulation. These results reveal novel forms of synaptic plasticity based on structural-functional changes of astrocyte-neuron interactions.

KW - Action Potentials

KW - Animals

KW - Astrocytes

KW - Calcium

KW - Dendritic Spines

KW - Female

KW - Hippocampus

KW - Long-Term Potentiation

KW - Male

KW - Mice

KW - Neuronal Plasticity

KW - Somatosensory Cortex

KW - Synaptic Transmission

U2 - 10.1523/JNEUROSCI.2401-14.2014

DO - 10.1523/JNEUROSCI.2401-14.2014

M3 - SCORING: Journal article

C2 - 25232111

VL - 34

SP - 12738

EP - 12744

JO - J NEUROSCI

JF - J NEUROSCI

SN - 0270-6474

IS - 38

ER -