Long-range GABAergic cells

GABA能神经元可以有效地同步它们的靶主细胞的活动，在特定的频率范围内产生振荡模式。我们实验室最近的证据表明，GABA能神经元间的招募对小鼠的海马区依赖的空间记忆有重要影响。为了促进对GABA能神经元间神经元如何促进同步网络活动和影响记忆的理解，我们开始在自由活动的小鼠中局部操纵GABA能神经元间神经元的活动。选择性干扰海马结构中GABA能神经元间的活动是通过病毒介导的光激活通道视紫红质-2的表达实现的。荧光标记物的同时表达导致了一类新的GABA能神经元的鉴定，这些神经元不是‘神经元间’，而是长距离投射，双向耦合海马体和内侧嗅觉皮质，即参与空间表征的两个主要脑区。在这里，我们建议利用体内电生理记录来研究这类新的GABA能神经元在行为小鼠中的作用。

GABAergic interneurones can effectively synchronize the activity of their target principal cells, giving rise to oscillatory patterns in defined frequency ranges. Recent evidence from our lab indicates that recruitment of GABAergic interneurones critically affects hippocampus-dependent spatial memory in mice. To advance the understanding of how GABAergic interneurones contribute to synchronous network activity and affect memory, we set out to manipulate the activity of GABAergic interneurones locally in freely moving mice. Selective interference with GABAergic interneurone activity in the hippocampal formation is achieved by virus-mediated expression of the light-activated Channelrhodopsin-2. The simultaneous expression of a fluorescent marker led to the identification of a novel class of GABAergic neurones that are not ‘interneurones’ but project long-distance, coupling bidirectionally the hippocampus and medial entorhinal cortex, i.e. two major brain regions involved in spatial representation. Here we propose to investigate the role of this novel class of GABAergic neurones employing electrophysiological in vivo recordings in behaving mice.