Heterosynaptic structural plasticity on local dendritic segments of hippocampal CA1 neurons

Cell Rep. 2015 Jan 13;10(2):162-9. doi: 10.1016/j.celrep.2014.12.016. Epub 2014 Dec 31.


Competition between synapses contributes to activity-dependent refinement of the nervous system during development. Does local competition between neighboring synapses drive circuit remodeling during experience-dependent plasticity in the cerebral cortex? Here, we examined the role of activity-mediated competitive interactions in regulating dendritic spine structure and function on hippocampal CA1 neurons. We found that high-frequency glutamatergic stimulation at individual spines, which leads to input-specific synaptic potentiation, induces shrinkage and weakening of nearby unstimulated synapses. This heterosynaptic plasticity requires potentiation of multiple neighboring spines, suggesting that a local threshold of neural activity exists beyond which inactive synapses are punished. Notably, inhibition of calcineurin, IP3Rs, or group I metabotropic glutamate receptors (mGluRs) blocked heterosynaptic shrinkage without blocking structural potentiation, and inhibition of Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) blocked structural potentiation without blocking heterosynaptic shrinkage. Our results support a model in which activity-induced shrinkage signal, and not competition for limited structural resources, drives heterosynaptic structural and functional depression during neural circuit refinement.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • CA1 Region, Hippocampal / physiology*
  • Calcineurin / chemistry
  • Calcineurin / metabolism
  • Calcium-Calmodulin-Dependent Protein Kinase Type 2 / antagonists & inhibitors
  • Calcium-Calmodulin-Dependent Protein Kinase Type 2 / metabolism
  • Dendrites / physiology*
  • Inositol 1,4,5-Trisphosphate Receptors / antagonists & inhibitors
  • Inositol 1,4,5-Trisphosphate Receptors / metabolism
  • Neuronal Plasticity
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Metabotropic Glutamate / antagonists & inhibitors
  • Receptors, Metabotropic Glutamate / metabolism
  • Synapses / physiology*


  • Inositol 1,4,5-Trisphosphate Receptors
  • Receptors, Metabotropic Glutamate
  • Calcium-Calmodulin-Dependent Protein Kinase Type 2
  • Calcineurin