Essential role of postsynaptic NMDA receptors in developmental refinement of excitatory synapses.

Zhong-wei Zhang, Matthew Peterson, Hong Liu

Proceedings of the National Academy of Sciences of the United States of America 2013 Jan 15

filter terms:

Neurons in the brains of newborns are usually connected with many other neurons through weak synapses. This early pattern of connectivity is refined through pruning of many immature connections and strengthening of the remaining ones. NMDA receptors (NMDARs) are essential for the development of excitatory synapses, but their role in synaptic refinement is controversial. Although chronic application of blockers or global knockdown of NMDARs disrupts developmental refinement in many parts of the brain, the ubiquitous presence of NMDARs makes it difficult to dissociate direct effects from indirect ones. We addressed this question in the thalamus by using genetic mosaic deletion of NMDARs. We demonstrate that pruning and strengthening of immature synapses are blocked in neurons without NMDARs, but occur normally in neighboring neurons with NMDARs. Our data support a model in which activation of NMDARs in postsynaptic neurons initiates synaptic refinement.

Citation

Zhong-wei Zhang, Matthew Peterson, Hong Liu. Essential role of postsynaptic NMDA receptors in developmental refinement of excitatory synapses. Proceedings of the National Academy of Sciences of the United States of America. 2013 Jan 15;110(3):1095-100