Learning-Dependent Plasticity of the Barrel Cortex Is Impaired by Restricting GABA-Ergic Transmission.
Learning-Dependent Plasticity of the Barrel Cortex Is Impaired by Restricting GABA-Ergic Transmission.
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DOI：
10.1371/journal.pone.0144415
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发表时间：
2015
期刊：
影响因子：
3.7
通讯作者：
Kossut M
中科院分区：
文献类型：
--
作者：
Posluszny A;Liguz-Lecznar M;Turzynska D;Zakrzewska R;Bielecki M;Kossut M
经验诱导的大脑皮层可塑性变化伴随着兴奋性和抑制性传递的改变。兴奋性驱动的增加是可塑性发生的必要条件，而抑制性信号的减少往往促进可塑性的发生。然而，在一些经验依赖性变化的情况下，抑制性相互作用的增加被注意到。我们之前报道过，小鼠在接受条件刺激（CS）后，对触须进行恐惧条件反射后，桶状皮层中抑制标记的数量增加，同时观察到受到条件刺激的触须的皮层表征区扩大。我们还观察到GABA水平随条件作用的增加而增加。在这里，为了发现未改变的GABA能信号是否对小鼠桶状皮质的学习依赖性重新布线是必要的，我们在条件反射时局部减少了桶状皮质中GABA的产生或减少了通过GABAA受体（GABAARs）的传递。3-巯基丙酸（3-MPA）是一种谷氨酸脱羧酶（GAD）抑制剂，注射到桶状皮质中，可以阻止学习诱导的条件振动表征的扩大。注射gabazine（一种GABAARs拮抗剂）后也观察到类似的效果。在行为水平上，一致的条件反应（停止头部运动以响应CS）受到损害。这些结果表明，gaba能系统的适当功能对于功能性皮层表征可塑性的表现和条件反应的发展都是必需的。
Experience-induced plastic changes in the cerebral cortex are accompanied by alterations in excitatory and inhibitory transmission. Increased excitatory drive, necessary for plasticity, precedes the occurrence of plastic change, while decreased inhibitory signaling often facilitates plasticity. However, an increase of inhibitory interactions was noted in some instances of experience-dependent changes. We previously reported an increase in the number of inhibitory markers in the barrel cortex of mice after fear conditioning engaging vibrissae, observed concurrently with enlargement of the cortical representational area of the row of vibrissae receiving conditioned stimulus (CS). We also observed that an increase of GABA level accompanied the conditioning. Here, to find whether unaltered GABAergic signaling is necessary for learning-dependent rewiring in the murine barrel cortex, we locally decreased GABA production in the barrel cortex or reduced transmission through GABAA receptors (GABAARs) at the time of the conditioning. Injections of 3-mercaptopropionic acid (3-MPA), an inhibitor of glutamic acid decarboxylase (GAD), into the barrel cortex prevented learning-induced enlargement of the conditioned vibrissae representation. A similar effect was observed after injection of gabazine, an antagonist of GABAARs. At the behavioral level, consistent conditioned response (cessation of head movements in response to CS) was impaired. These results show that appropriate functioning of the GABAergic system is required for both manifestation of functional cortical representation plasticity and for the development of a conditioned response.