Functional local connections with differential activity-dependence and critical periods surrounding the primary auditory cortex in rat cerebral slices
Functional local connections with differential activity-dependence and critical periods surrounding the primary auditory cortex in rat cerebral slices
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DOI：
10.1016/j.neuroimage.2006.09.030
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发表时间：
2007-01-15
期刊：
影响因子：
5.7
通讯作者：
Shibuki, Katsuei
中科院分区：
文献类型：
--
作者：
Hishida, Ryuichi;Kamatani, Daiki;Shibuki, Katsuei
感觉信息是在神经网络中处理的，神经网络将初级感觉皮质与周围的高级区域连接起来。在这里，我们研究了大鼠脑片初级听觉皮质(41区)与周围区域(20、36、18a和39区)之间的局部联系的特性。重复电刺激所诱发的神经活动主要是利用线粒体黄素蛋白产生的内源性荧光的活动依赖性变化来可视化的，这些变化主要反映了多突触谷氨酸能传递产生的活动。与初级(41区)和次级(20区和36区)听觉皮质之间的多突触反馈传播相比，多突触前馈传播占主导地位，而在其他通路中这种趋势不太明显。在41区和20区之间的Laver V刺激后，观察到具有相同优势的长的(>；1 mm)区域间传播，并且不受切断底层白质的影响。用钙离子显像法研究了低频刺激引起的神经活动的活动依赖性变化。仅在初级至次级听皮层的多突触前馈通路中观察到多突触钙离子活性的显著增强。使用黄素蛋白荧光成像研究了区域41和20之间的连接的经验依赖性。在P12时损毁耳蜗区，41~20区的活动减少，而在P28时损毁耳蜗区的活动不明显，而在P28时损毁耳蜗区20~41区的活动，提示多突触前馈联系的关键期在P28之前，多突触反馈联系的关键期在P28之后。(C)2006 Elsevier Inc.保留所有权利。
Sensory information is processed in neural networks connecting the primary sensory cortices with surrounding higher areas. Here, we investigated the properties of local connections between the primary auditory cortex (area 41) and surrounding areas (areas 20, 36, 18a and 39) in rat cerebral slices. Neural activities elicited by repetitive electrical stimulation were visualized using the activity-dependent changes in endogenous fluorescence derived from mitochondrial flavoproteins, which mostly reflect activities produced by polysynaptic glutamatergic transmission. Polysynaptic feedforward propagation was dominant compared with the corresponding polysynaptic feedback propagation between the primary (area 41) and secondary (areas 20 and 36) auditory cortices, while such a tendency was less clear in other pathways. Long inter-areal (> 1 mm) propagation with the same dominancy was observed after laver V stimulation between areas 41 and 20, and was not affected by cutting the underlying white matter. Activity-dependent changes in neural activities induced by low-frequency stimulation in the presence of I mu M bicuculline were investigated using Ca2+ imaging. Significant potentiation of the polysynaptic Ca2+ activities was only observed in polysynaptic feedforward pathways from the primary to secondary auditory cortices. Experience-dependence of the connections between areas 41 and 20 was investigated using flavoprotein fluorescence imaging. The activities from areas 41 to 20 were reduced by cochlear lesions produced at P12 but not at P28, while the activities from areas 20 to 41 were reduced by the lesions at P28, suggesting the critical period for the polysynaptic feedforward connection was before P28, while for the polysynaptic feedback connection was after P28. (c) 2006 Elsevier Inc. All rights reserved.