24小时热门版块排行榜    

CyRhmU.jpeg
查看: 143  |  回复: 0
当前主题已经存档。

轩辕之客

金虫 (小有名气)


[交流] Nature :早衰蛋白控制神经传输物质的释放

Nature 460, 632-636 (30 July 2009) | doi:10.1038/nature08177

Presenilins are essential for regulating neurotransmitter release

Chen Zhang1,2, Bei Wu1, Vassilios Beglopoulos1, Mary Wines-Samuelson1, Dawei Zhang1, Ioannis Dragatsis3, Thomas C. Südhof2 & Jie Shen1

1 Center for Neurologic Diseases, Brigham & Women's Hospital, Program in Neuroscience, Harvard Medical School, Boston, Massachusetts 02115, USA
2 Department of Molecular and Cellular Physiology, Howard Hughes Medical Institute, Stanford University School of Medicine, Palo Alto, California 94304, USA
3 Department of Physiology, The University of Tennessee, Health Science Center, Memphis, Tennessee 38163, USA

Mutations in the presenilin genes are the main cause of familial Alzheimer's disease. Loss of presenilin activity and/or accumulation of amyloid-peptides have been proposed to mediate the pathogenesis of Alzheimer's disease by impairing synaptic function1, 2, 3, 4, 5. However, the precise site and nature of the synaptic dysfunction remain unknown. Here we use a genetic approach to inactivate presenilins conditionally in either presynaptic (CA3) or postsynaptic (CA1) neurons of the hippocampal Schaeffer-collateral pathway. We show that long-term potentiation induced by theta-burst stimulation is decreased after presynaptic but not postsynaptic deletion of presenilins. Moreover, we found that presynaptic but not postsynaptic inactivation of presenilins alters short-term plasticity and synaptic facilitation. The probability of evoked glutamate release, measured with the open-channel NMDA (N-methyl-d-aspartate) receptor antagonist MK-801, is reduced by presynaptic inactivation of presenilins. Notably, depletion of endoplasmic reticulum Ca2+ stores by thapsigargin, or blockade of Ca2+ release from these stores by ryanodine receptor inhibitors, mimics and occludes the effects of presynaptic presenilin inactivation. Collectively, these results indicate a selective role for presenilins in the activity-dependent regulation of neurotransmitter release and long-term potentiation induction by modulation of intracellular Ca2+ release in presynaptic terminals, and further suggest that presynaptic dysfunction might be an early pathogenic event leading to dementia and neurodegeneration in Alzheimer's disease.

原文下载:http://d.namipan.com/d/dfaf22de7 ... de06f1a110a079d1700
http://d.namipan.com/d/dfaf22de7391812fe751559102045de06f1a110a079d1700
回复此楼
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖
相关版块跳转 我要订阅楼主 轩辕之客 的主题更新
普通表情 高级回复(可上传附件)
信息提示
请填处理意见