Maru E, Takahashi L K, Iwahara S
Brain Res. 1979 Mar 16;163(2):223-34. doi: 10.1016/0006-8993(79)90351-2.
The effects of median raphe lesions on the hippocampal EEG were examined in freely moving rats. First, median raphe lesions, including those restricted to the median raphe nucleus, unequivocally produced hippocampal low-frequency theta activity (5.8 Hz, SD = 0.47 Hz) during relaxed immobility which was not observed under normal conditions. This lesion-induced theta activity during immobiliy continued for at least 20 days, and was markedly suppressed by atropine sulfate (10 mg/kg, i.p.). On the other hand, reticular formation lesions had little effect on either hippocampal EEG patterns during immobility, movement or PS. Second, the mean frequency of theta activity was significantly reduced during movement and PS on the day following the median raphe lesion. These findings suggest a raphe-hippocampal pathway in which the median raphe mucleus plays a major role in hippocampal desynchronization (irregular pattern) by exerting an inhibitory influence on the hippocompal theta generating or facilitating mechanism. Thus the theta activity will be induced by the disinhibition following median raphe lesions.
在自由活动的大鼠中研究了中缝核损伤对海马脑电图的影响。首先，中缝核损伤，包括那些局限于中缝核的损伤，在放松不动期间明确地产生了海马低频θ活动（5.8赫兹，标准差 = 0.47赫兹），而在正常条件下未观察到这种情况。这种损伤诱导的不动期间的θ活动持续至少20天，并且被硫酸阿托品（10毫克/千克，腹腔注射）显著抑制。另一方面，网状结构损伤对不动、运动或快速眼动睡眠期间的海马脑电图模式几乎没有影响。其次，在中缝核损伤后的第二天，运动和快速眼动睡眠期间θ活动的平均频率显著降低。这些发现提示了一条中缝 - 海马通路，其中中缝核通过对海马θ产生或促进机制施加抑制性影响，在海马去同步化（不规则模式）中起主要作用。因此，中缝核损伤后的去抑制将诱导θ活动。
