期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2002
卷号：99
期号：11
页码：7717-7721
DOI：10.1073/pnas.102088899
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The serine protease, tissue-type plasminogen activator (tPA) is a key regulator of extracellular proteolytic cascades. We demonstrate a requirement for tPA signaling in the experience-dependent plasticity of mouse visual cortex during the developmental critical period. Proteolytic activity by tPA in the binocular zone was typically increased within 2 days of monocular deprivation (MD). This regulation failed to occur in glutamic acid decarboxylase (GAD) 65 knockout mice, an animal model of impaired ocular dominance plasticity because of reduced {gamma}-aminobutyric acid (GABA)-mediated transmission described previously. Loss of responsiveness to the deprived eye consequent to MD was conversely suppressed in mice lacking tPA despite normal levels of neuronal activity. Plasticity was restored in a gene dose-dependent manner, or by direct tPA infusion. Permissive amounts of tPA may, thus, couple functional to structural changes downstream of the excitatory-inhibitory balance that triggers visual cortical plasticity. Our results not only support a molecular cascade leading to neurite outgrowth after sensory deprivation, but also identify a valuable tool for further proteomic and genomic dissection of experience-dependent plasticity downstream of electrical activity.
