Xu Changqing, Datta Subimal, Wu Min, Alreja Meenakshi
Department of Psychiatry, CMHC 335 A, Yale University School of Medicine, 34 Park Street, New Haven, CT 06508, USA.
Eur J Neurosci. 2004 Apr;19(8):2299-309. doi: 10.1111/j.0953-816X.2004.03316.x.
Hippocampal learning and memory tasks are tightly coupled to the hippocampal theta rhythm, which is critically dependent on the medial septum/diagonal band of Broca (MSDB) although the underlying mechanisms remain unclear. The MSDB sends both cholinergic and GABAergic projections to the hippocampus. Here we show that: (i) septo-hippocampal GABAergic but not cholinergic neurons have a pacemaking current, the H-current, and that its selective blockade by ZD7288 reduces their spontaneous firing in rat brain slices; and (ii), local infusions of ZD7288 into the MSDB reduce exploration and sensory evoked hippocampal theta bursts in behaving rats. Thus, the H-current in septohippocampal GABAergic neurons modulates the hippocampal theta rhythm.
海马体的学习和记忆任务与海马体θ节律紧密相关，尽管其潜在机制尚不清楚，但该节律严重依赖于内侧隔区/布罗卡斜角带（MSDB）。MSDB向海马体发送胆碱能和γ-氨基丁酸能（GABAergic）投射。在此我们表明：（i）隔区-海马体的GABA能神经元而非胆碱能神经元具有起搏电流，即H电流，并且ZD7288对其选择性阻断会降低大鼠脑片中它们的自发放电；以及（ii）向MSDB局部注射ZD7288会减少行为大鼠的探索行为和感觉诱发的海马体θ波爆发。因此，隔区-海马体GABA能神经元中的H电流调节海马体θ节律。
