Reactivation of ocular dominance plasticity in the adult visual cortex.
In young animals, monocular deprivation leads to an ocular dominance shift, whereas in adults after the critical period there is no such shift. Chondroitin sulphate proteoglycans (CSPGs) are components of the extracellular matrix (ECM) inhibitory for axonal sprouting. We tested whether the developmental maturation of the ECM is inhibitory for experience-dependent plasticity in the visual cortex. The organization of CSPGs into perineuronal nets coincided with the end of the critical period and was delayed by dark rearing. After CSPG degradation with chondroitinase-ABC in adult rats, monocular deprivation caused an ocular dominance shift toward the nondeprived eye. The mature ECM is thus inhibitory for experience-dependent plasticity, and degradation of CSPGs reactivates cortical plasticity.
Pizzorusso
Tommaso
T
Scuola Normale Superiore, 56100 Pisa, Italy. tommaso@in.pi.cnr.it
Medini
Paolo
P
Berardi
Nicoletta
N
Chierzi
Sabrina
S
Fawcett
James W
JW
Maffei
Lamberto
L
D000818:Animals; D001369:Axons / Q000502:physiology; D019765:Chondroitin ABC Lyase / Q000378:metabolism*; D011508:Chondroitin Sulfate Proteoglycans / Q000378:metabolism*; D003624:Darkness; D023882:Dominance, Ocular; D005109:Extracellular Matrix / Q000378:metabolism*; D016326:Extracellular Matrix Proteins / Q000378:metabolism; D006025:Glycosaminoglycans / Q000378:metabolism; D037181:Lectins, C-Type; D008027:Light; D009419:Nerve Tissue Proteins / Q000378:metabolism; D058580:Neurocan; D009473:Neuronal Plasticity; D009474:Neurons / Q000502:physiology; D051381:Rats; D013569:Synapses / Q000502:physiology; D013997:Time Factors; D014792:Visual Acuity; D014793:Visual Cortex / Q000502:physiology*
D011508:Chondroitin Sulfate Proteoglycans; D016326:Extracellular Matrix Proteins; D006025:Glycosaminoglycans; D037181:Lectins, C-Type; D009419:Nerve Tissue Proteins; D058580:Neurocan; C076817:NCAN protein, human; D019765:Chondroitin ABC Lyase