生物谷報(bào)道：美國(guó)麻省理工學(xué)院教授,、諾貝爾獎(jiǎng)得主利根川進(jìn)在２4日的美國(guó)《科學(xué)》雜志網(wǎng)絡(luò)版上報(bào)告說(shuō),，他們開(kāi)發(fā)出一種可自由開(kāi)關(guān)實(shí)驗(yàn)鼠腦神經(jīng)回路的技術(shù)。
利根川進(jìn)是日本唯一一名諾貝爾生理學(xué)或醫(yī)學(xué)獎(jiǎng)得主,，現(xiàn)為美國(guó)麻省理工學(xué)院腦科學(xué)中心負(fù)責(zé)人,。他領(lǐng)導(dǎo)的研究小組通過(guò)轉(zhuǎn)基因技術(shù)將控制破傷風(fēng)毒素合成的基因植入實(shí)驗(yàn)鼠，并使基因只在實(shí)驗(yàn)鼠某些特定的神經(jīng)細(xì)胞中發(fā)揮作用,。
破傷風(fēng)毒素生效后,，神經(jīng)細(xì)胞就不能釋放出信號(hào)，神經(jīng)回路被切斷,。如果在實(shí)驗(yàn)鼠的飼料中添加鹽酸多西環(huán)素,，抑制毒素活動(dòng)，神經(jīng)回路又會(huì)得以恢復(fù),。如果再喂食不含鹽酸多西環(huán)素的普通飼料,，實(shí)驗(yàn)鼠神經(jīng)回路會(huì)再次被斷開(kāi)。
在實(shí)驗(yàn)中,，研究人員利用這種技術(shù)自由開(kāi)閉實(shí)驗(yàn)鼠大腦海馬部位的三突觸回路,。利根川進(jìn)認(rèn)為，這一成果將成為探究大腦記憶和學(xué)習(xí)能力的重要研究手段,。（生物谷援引新華網(wǎng)）
生物谷推薦原始出處：
Published Online January 24, 2008
Science DOI: 10.1126/science.1151120
Submitted on September 28, 2007
Accepted on January 11, 2008
Transgenic Inhibition of Synaptic Transmission Reveals Role of CA3 Output in Hippocampal Learning
Toshiaki Nakashiba 1, Jennie Z. Young 1, Thomas J. McHugh 1, Derek L. Buhl 1, Susumu Tonegawa 1*
1 The Picower Institute for Learning and Memory, Howard Hughes Medical Institute, RIKEN-MIT Neuroscience Research Center, Department of Biology and Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
* To whom correspondence should be addressed.
Susumu Tonegawa , E-mail: [email protected]
The hippocampus is an area of the brain involved in learning and memory. It contains parallel excitatory pathways referred to as the trisynaptic pathway (which carries information from the entorhinal cortex dentate gyrus CA3 CA1 entorhinal cortex) and the monosynaptic pathway (which connects entorhinal cortex CA1 entorhinal cortex). We developed a generally applicable tetanus toxin-based method for transgenic mice that permits inducible and reversible inhibition of synaptic transmission and applied it to the trisynaptic pathway while preserving transmission in the monosynaptic pathway. We found that synaptic output from CA3 in the trisynaptic pathway is dispensable and the short monosynaptic pathway is sufficient for incremental spatial learning. In contrast, the full trisynaptic pathway containing CA3 is required for rapid, one-trial contextual learning, for pattern completionbased memory recall and for spatial tuning of CA1 cells.
