Disinhibition of hippocampal pyramidal cells during the transition into theta rhythm.
Disinhibition of hippocampal pyramidal cells during the transition into theta rhythm.
复制标题
在过渡到 θ 节律期间海马锥体细胞的去抑制。
DOI：
10.1007/bf00227774
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发表时间：
1993
影响因子：
2
通讯作者：
Stewart,M
中科院分区：
文献类型：
--
作者：
Stewart,M
在自由活动和睡眠的大鼠中，在从非θ脑电图（EEG）状态到θ EEG状态的转换过程中，检查海马复合棘细胞（假定为锥体细胞）和θ细胞（假定为中间神经元）的活动。θ细胞放电率在以EEG过渡为中心的1-s周期内相对于周围1-s周期显著降低（归一化率±SEM）：“非θ”周期为1.05±0.02，“过渡”周期为0.59±0.03，“θ”周期为1.36±0.04（n= 26个细胞）。相反，复合锋电位细胞放电在过渡期显著增加：“非θ”期为0.51±0.11，“过渡”期为2.24±0.19，“θ”期为0.24±0.04（n= 27个细胞）。这种完全不同的活动表明，θ细胞必须在过渡期间被积极抑制。在过渡期间，复合棘细胞的活动增加可能只是从中间神经元的抑制控制中释放出来。θ细胞抑制的模式与增加的复合棘波细胞活性一起出现是过渡到θ EEG状态的一般性质，与行为无关。这表明，在隔传入活动增加（GABA能细胞活性大于胆碱能细胞活性）最初抑制海马中间神经元。抑制是不持续的，因为活动依赖性降低的效力septointerneuronal抑制，离开有节奏的兴奋性（胆碱能）septointerneuronal输入，连同主要的细胞输入，以增加interneuron放电率。
The activity of hippocampal complex-spike cells (presumed pyramidal cells) and theta cells (presumed interneurons) was examined during transitions from non-theta electroencephalogram (EEG) states to theta EEG states in freely moving and sleeping rats. Theta cell firing rates were significantly depressed in a 1-s period centered on the EEG transition relative to the surrounding 1-s periods (normalized rates±SEM): 1.05±0.02 for the “non-theta” period, 0.59±0.03 for the “transition” period, and 1.36±0.04 for the “theta” period (n= 26 cells). Conversely, complex-spike cell firing was significantly increased during the transition period: 0.51±0.11 for the “non-theta” period, 2.24±0.19 for the “transition” period, and 0.24±0.04 for the “theta” period (n= 27 cells). This diametrically altered activity indicates that theta cells must be actively inhibited during the transition. The increased activity in complex-spike cells during the transition may be simply a release from inhibitory control by interneurons. The pattern of theta cell inhibition together with increased complex-spike cell activity appears to be a general property of transitions into the theta EEG state, irrespective of behavior. It is suggested that increased activity in septal afferents (GABAergic cell activity greater than cholinergic cell activity) initially inhibits hippocampal interneurons. The inhibition is not sustained because of an activity-dependent decrease in the potency of the septointerneuronal inhibition, leaving the rhythmic excitatory (cholinergic) septointerneuronal inputs, together with principal cell inputs, to increase interneuron firing rates.