与人丧失视觉后听觉会变得更灵敏一样，失明大鼠胡须的功能也会得到提升。日本科学家最新从分子层面解开了其中之谜，这项成果有望用于帮助丧失某种感觉的患者提高康复训练效果。
横滨市立大学研究人员日前在美国《神经元》 Neuron 杂志网络版上发表报告说，他们主要的研究对象是大鼠大脑的桶状皮质，这个区域接收通过胡须传递到大脑的外界信息。
研究人员发现，丧失视觉的大鼠桶状皮质区域的神经传递物质血清素会比正常大鼠有所增加，传递信号的突触中受体数量也增加到正常大鼠的两倍。这些都表明失明大鼠胡须的触觉变得更加灵敏。
研究人员说，本项研究发现了动物用留存感觉功能弥补失明缺陷的具体机理。这一研究结果将有助于提高感觉缺损患者的康复训练水平。（生物谷Bioon.com）
生物谷推荐相关文章：
Neuron doi:10.1016/j.neuron.2011.01.016
Serotonin Mediates Cross-Modal Reorganization of Cortical Circuits
Susumu Jitsuki, Kiwamu Takemoto, Taisuke Kawasaki, Hirobumi Tada, Aoi Takahashi, Carine Becamel, Akane Sano, Michisuke Yuzaki, R. Suzanne Zukin, Edward B. Ziff, Helmut W. Kessels, Takuya Takahashi
Highlights
Visual deprivation (VD) drives AMPA receptors into synapses in the rat barrel cortex
Seoronin mediates VD-induced facilitation of synaptic AMPA receptor delivery
VD increases activation of ERK and increase of phosphorylation of GluR1 at Ser845
VD sharpens the map in the barrel cortex
Summary
Loss of one type of sensory input can cause improved functionality of other sensory systems. Whereas this form of plasticity, cross-modal plasticity, is well established, the molecular and cellular mechanisms underlying it are still unclear. Here, we show that visual deprivation (VD) increases extracellular serotonin in the juvenile rat barrel cortex. This increase in serotonin levels facilitates synaptic strengthening at layer 4 to layer 2/3 synapses within the barrel cortex. Upon VD, whisker experience leads to trafficking of the AMPA-type glutamate receptors (AMPARs) into these synapses through the activation of ERK and increased phosphorylation of AMPAR subunit GluR1 at the juvenile age when natural whisker experience no longer induces synaptic GluR1 delivery. VD thereby leads to sharpening of the functional whisker-barrel map at layer 2/3. Thus, sensory deprivation of one modality leads to serotonin release in remaining modalities, facilitates GluR1-dependent synaptic strengthening, and refines cortical organization.
