过刊浏览

在体神经元胞外记录用于大脑皮层可塑性研究

陈小默, 乔志梅, 高上凯, 洪波

清华大学医学院生物医学工程系.北京 100084

摘要

神经元网络可塑性是大脑学习和记忆功能的基础,可塑性的变化也是某些脑功能疾病的成因。研究大脑皮层可塑性不仅可以为认识可塑性机制提供基本方法,也可对自然衰老过程和神经退行性疾病的病理过程进行观测,进而可以为评价抗衰老药物和治疗神经退行性疾病提供新方法。该文基于经典的大鼠胡须配对模型建立了一套实验方案,通过在体细胞外记录实验的数据分忻,比较修剪胡须后相同时间内神经元感受野不对称变化程度的差异,衡量不同生理条件下大鼠体感皮层神经元网络可塑性。该文以中年和青年大鼠体感皮层神经元网络可塑性比较为例,详细介绍了实验方法中的关键技术和操作,如皮层D2功能柱的定位和D2功能柱内不同层神经元的定位等,结果和我室以前相关研究证明了此实验方案的可行性。

关键词： 神经元网络可塑性; 感受野; 体感皮层; 衰老; 电生理记录

{sl In vivo} extracellular neural recording for the study of cortical plasticity

Chen Xiaomo, Qiao Zhimei, Gao Shangkai, Hong Bo

Department of Biomedical Engineering, School of Medicine, Tsinghua University.Beijing 100084

Abstract

Neural network plasticity is fundamental for learning and memory. Its abnormal change underlies some neural diseases. Measurement of the plasticity of cortex can help understand the mechanism of plasticity, and provide a quantitative way to observe the neural process of natural aging and neurodegenerative diseases, which may lead to a new approach for evaluation of anti-aging drugs and new medical treatments for neurodegenerative diseases. In this study, a systematic method was established based on whisker pairing （WP） experiment to measure the network plasticity in the barrel cortex in rat. WP experiment is a classical experiment to study the effect of innocuous bias of the flow of sensory activity from the whiskers for certain periods in awake and behaving rats on the receptive field organization in S 1 barrel cortex neurons. In the experiment, one pair of adjacent whiskers D2 and D3 remained intact while others were being trimmed throughout a certain period. After that, receptive fields of single cells in the contralateral barrel were analyzed by post-stimulus time histogram after certain days of WP and compared with the controls. In the control group, response magnitudes to surrounding whiskers DI and D3 deflection were not significantly different. However, after WP, a bias occurred in response to paired surrounding whisker D3 relative to the opposite trimmed surrounding whisker D1. In this study, by comparing the bias degree in rats in different groups after WP, a quantitative method was established to compare cortical plasticity. Example of corical plasticity comparison between adolescent and mature rats was employed in this paper to illustrate our method. The key techniques of this method such as the identification of D2 barrels, supragranular （L2-3） and barrel layer （L4） in real-time were described in details. The feasibility of this approach was further verified by compendious report of results and our previous study regarding cortical plasticity comparison between adolescent and mature rats.

Key words: neural network plasticity;receptive fields;Somatosensory cortex;Aging;electrophysiological recording

收稿日期：　　录用日期：

通讯作者：　　E-mail:

引用本文：

陈小默, 乔志梅, 高上凯, 洪波. 在体神经元胞外记录用于大脑皮层可塑性研究[J]. 生理学报 2007; 59 (6): 851-857.

Chen Xiaomo, Qiao Zhimei, Gao Shangkai, Hong Bo. {sl In vivo} extracellular neural recording for the study of cortical plasticity. Acta Physiol Sin 2007; 59 (6): 851-857 (in Chinese with English abstract).