The behavior of mossy cells of the rat dentate gyrus during theta oscillationsin vivo
The behavior of mossy cells of the rat dentate gyrus during theta oscillationsin vivo
复制标题
大鼠齿状回苔藓细胞在体内θ振荡过程中的行为
DOI：
10.1016/0306-4522(93)90005-z
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发表时间：
1993
期刊：
影响因子：
3.3
通讯作者：
M. Descheˆnes
中科院分区：
文献类型：
--
作者：
I. Soltesz;J. Bourassa;M. Descheˆnes
对氯胺酮-二嗪麻醉大鼠背齿状回苔藓细胞（n = 6，细胞内注射生物胞素鉴定）进行细胞内电流钳记录。在脑电图θ节律（4-6 Hz）期间，放置在裂缝附近对侧海马背侧的大电极记录下，苔藓细胞显示出低频（4-6 Hz）的细胞膜内电位振荡，这似乎与脑电图θ节律相锁定。细胞内θ节律的频率与膜电位无关。然而，细胞内和脑电图θ节律之间的相位差以及细胞内θ振荡的振幅是电压依赖性的。这些发现与有节奏的gaba受体介导的抑制性突触后电位有助于细胞内θ节律发生的假设一致。事实上，苔藓细胞对内嗅皮层的电刺激表现出早期、快速的抑制性突触后电位，这很可能代表了gaba受体介导的事件，表明苔藓细胞具有功能性gaba受体。在静息膜电位下，苔藓细胞在脑电图θ节律的每个周期都不放电，但很少放电（< 1 Hz）。然而，当他们放电时，他们优先与脑电图θ节奏的峰值正相一致。对两个具有轴突内分子层的苔藓状细胞的重建表明，在θ波振荡期间，这种微弱放电的苔藓状细胞对其他齿状回神经元的影响的空间范围可能在隔颞方向上有几毫米。综上所述，这些研究结果表明，氯胺酮-二嗪麻醉下大鼠门部苔藓细胞参与海马形成的θ波振荡，在此过程中，它们的低频放电可能有助于大量空间分布的突触后神经元的锁相，这些突触后神经元位于齿状回的内分子层。
Intracellular current clamp recordings were obtained from mossy cells (n = 6, identified by intracellular injection of biocytin) of the dorsal dentate gyrus from rats under ketamine-xylazine anesthesia. During electroencephalographic theta rhythm (4–6 Hz), recorded with a macroelectrode placed in the contralateral dorsal hippocampus near the fissure, mossy cells displayed intracellular membrane potential oscillations at low frequencies (4–6 Hz) which appeared to be phase locked to the electroencephalographic theta rhythm.The frequency of the intracellular theta rhythm was independent of the membrane potential. However, the phase difference between the intracellular and the electroencephalographic theta rhythms as well as the amplitude of the intracellular theta oscillations were voltage-dependent. These findings are consistent with the hypothesis that rhythmic GABAAreceptor-mediated inhibitory postsynaptic potentials contribute to the genesis of the intracellular theta rhythm. Indeed, mossy cells displayed an early, fast inhibitory postsynaptic potential in response to electrical stimulation of the entorhinal cortex, which most likely represents a GABAAreceptor-mediated event, indicating that mossy cells possess functional GABAAreceptors. At the resting membrane potential, mossy cells did not fire at each cycle of the electroencephalographic theta rhythm but fired only rarely (< 1 Hz). However, when they did fire they did so preferentially in phase with the peak positivity of the electroencephalographic theta rhythm. Reconstruction of two mossy cells with axonal projections to the inner molecular layer showed that the spatial extent of the influence such weakly discharging mossy cells may have on other dentate gyrus neurons during theta oscillations can be several millimeters in the septotemporal direction.In conclusion, these findings show that mossy cells of the rat hilus during ketamine-xylazine anesthesia participate in theta oscillations of the hippocampal formation, during which their low-frequency firing may contribute to the phase-locking of a large number of spatially distributed postsynaptic neurons with postsynaptic sites in the inner molecular layer of the dentate gyrus.
兴奋阻断揭示了大鼠海马切片中记录的齿状棘肺门神经元的抑制。
影响因子：
2.5
作者：
Scharfman,HE
通讯作者：
Scharfman,HE
通过细胞内钙螯合保护齿状门细胞免受长期刺激。
DOI：
10.1126/science.2508225
发表时间：
1989
期刊：
Science (New York, N.Y.)
影响因子：
--
作者：
Scharfman,HE;Schwartzkroin,PA
通讯作者：
Schwartzkroin,PA