The effect of descending theta rhythmic input from the septohippocampal system on firing in the supramammillary nucleus.
The effect of descending theta rhythmic input from the septohippocampal system on firing in the supramammillary nucleus.
复制标题
来自间隔海马系统的下降 theta 节律输入对乳头上核放电的影响。
DOI：
10.1016/j.brainres.2006.02.117
复制
发表时间：
2006
期刊：
影响因子：
--
通讯作者：
Kocsis,Bernat
中科院分区：
文献类型：
--
作者：
Kocsis,Bernat
乳头体上核（suprammillary nucleus，SUM）是将行为依赖性驱动传递给边缘系统θ节律的间隔发生器的上行通路的一部分。然而，SUM与隔海马系统紧密相连，并且有强有力的证据表明隔和SUM都能够产生θ节律活动。本研究探讨了可能的作用，一个下行的节奏输入的SUM使用同时记录海马EEG和SUM神经元活动在麻醉大鼠。基于傅立叶相位分析的记录，其中快速θ节律性活动引起的尾巴捏，并在其中一个较慢的θ节律持续停止后的感觉刺激。结果发现，一个亚群的SUM神经元的放电遵循海马θ波与恒定的时间延迟，而不是一个恒定的相位，这表明在减速与从感官引起的θ波自发θ波节律的转变，他们遵循一个下降的节奏输入，最有可能从内侧隔。第二组的神经元，在海马θ峰发射，并没有显示出这种关系，证明在群体的异质性的节律SUM神经元和他们可能的作用，θ代。结合以前的研究集中在上升θ驱动器的作用，从总和，这些结果表明皮质下θ发电机之间的动态双向耦合。因此，在某些状态下，有节奏地发射SUM神经元导致隔θ振荡器，在其他情况下，方向可能会逆转，SUM遵循隔起源的θ驱动。
The supramammillary nucleus (SUM) is part of an ascending pathway conveying behavior-dependent drive to the septal generator of limbic theta rhythm. The SUM is, however, reciprocally connected to the septohippocampal system and there is strong evidence that both septum and SUM are capable of generating theta rhythmic activity. The present study examined the possible role of a descending rhythmic input to the SUM using simultaneously recorded hippocampal EEG and SUM neuronal activity in anesthetized rats. Fourier based phase analysis was performed on recordings in which fast theta rhythmic activity was elicited by tail pinch and in which a slower theta rhythm persisted after cessation of the sensory stimulus. It was found that the firing of a subpopulation of SUM neurons followed the hippocampal theta waves with a constant time delay, rather than a constant phase, suggesting that during deceleration associated with a shift from sensory-elicited theta to spontaneous theta rhythm they followed a descending rhythmic input, most likely from the medial septum. Neurons of a second group, which fired at the hippocampal theta peaks, did not show such relationship demonstrating heterogeneity in the population of rhythmic SUM neurons and their possible roles in theta generation. Combined with previous studies focusing on the role of the ascending theta drive from the SUM, these results demonstrate dynamic bidirectional coupling between subcortical theta generators. Thus, during certain states, rhythmically firing SUM neurons lead the septal theta oscillator, in others the direction may reverse and SUM follows a theta drive of septal origin.