perineuronal net
Also written as: PNN — perineuronal net
Extracellular matrix structure surrounding certain neurons that regulates synaptic plasticity and stability.
Full Definition
Perineuronal nets (PNNs) are specialized extracellular matrix structures that form around specific subsets of neurons, particularly parvalbumin-positive interneurons. These nets consist of chondroitin sulfate proteoglycans, hyaluronic acid, and other matrix molecules that create a mesh-like structure around the neuron's soma and proximal dendrites. PNNs play crucial roles in restricting synaptic plasticity, stabilizing synaptic connections, and protecting neurons from oxidative stress. The development and maturation of PNNs coincide with the closure of critical periods for experience-dependent plasticity.
Usage
Usage note: Commonly abbreviated as PNN; specify the neuron types when discussing distribution patterns.
In Context
- "Chondroitinase treatment degraded perineuronal nets and reopened cortical plasticity in adult mice." — Plasticity research
- "The study examined perineuronal net formation around inhibitory interneurons during development." — Developmental neurobiology