與人喪失視覺后聽覺會變得更靈敏一樣,，失明大鼠胡須的功能也會得到提升,。日本科學(xué)家最新從分子層面解開了其中之謎，這項成果有望用于幫助喪失某種感覺的患者提高康復(fù)訓(xùn)練效果,。
橫濱市立大學(xué)研究人員日前在美國《神經(jīng)元》 Neuron 雜志網(wǎng)絡(luò)版上發(fā)表報告說,，他們主要的研究對象是大鼠大腦的桶狀皮質(zhì)，這個區(qū)域接收通過胡須傳遞到大腦的外界信息,。
研究人員發(fā)現(xiàn),，喪失視覺的大鼠桶狀皮質(zhì)區(qū)域的神經(jīng)傳遞物質(zhì)血清素會比正常大鼠有所增加，傳遞信號的突觸中受體數(shù)量也增加到正常大鼠的兩倍,。這些都表明失明大鼠胡須的觸覺變得更加靈敏,。
研究人員說，本項研究發(fā)現(xiàn)了動物用留存感覺功能彌補(bǔ)失明缺陷的具體機(jī)理,。這一研究結(jié)果將有助于提高感覺缺損患者的康復(fù)訓(xùn)練水平,。（生物谷Bioon.com）
生物谷推薦相關(guān)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.
