Mechanisms of homeostatic plasticity in the excitatory synapse

Dominique Fernandes, Ana Luísa Carvalho
J. Neurochem.. 2016-07-01; 139(6): 973-996
DOI: 10.1111/jnc.13687

PubMed

Fernandes D(1)(2), Carvalho AL(1)(3).

Author information:
(1)CNC-Centre for Neuroscience and Cell Biology, University of Coimbra, Coimbra,
Portugal.
(2)PDBEB-Doctoral Program in Experimental Biology and Biomedicine,
Interdisciplinary Research Institute (III-UC), University of Coimbra, Coimbra,
Portugal.
(3)Department of Life Sciences, University of Coimbra, Coimbra, Portugal.

Brain development, sensory information processing, and learning and memory
processes depend on Hebbian forms of synaptic plasticity, and on the remodeling
and pruning of synaptic connections. Neurons in networks implicated in these
processes carry out their functions while facing constant perturbation;
homeostatic responses are therefore required to maintain neuronal activity
within functional ranges for proper brain function. Here, we will review
in vitro and in vivo studies demonstrating that several mechanisms underlie
homeostatic plasticity of excitatory synapses, and identifying participant
molecular players. Emerging evidence suggests a link between disrupted
homeostatic synaptic plasticity and neuropsychiatric and neurologic disorders.
Hebbian forms of synaptic plasticity, such as long-term potentiation (LTP),
induce long-lasting changes in synaptic strength, which can be destabilizing and
drive activity to saturation. Conversely, homeostatic plasticity operates to
compensate for prolonged activity changes, stabilizing neuronal firing within a
dynamic physiological range. We review mechanisms underlying homeostatic
plasticity, and address how neurons integrate distinct forms of plasticity for
proper brain function. This article is part of a mini review series: « Synaptic
Function and Dysfunction in Brain Diseases ».