Effects of cholinergic modulation on responses of neocortical neurons to fluctuating input.
Effects of cholinergic modulation on responses of neocortical neurons to fluctuating input.
复制标题
胆碱能调节对新皮质神经元对波动输入的反应的影响。
DOI：
10.1093/cercor/7.6.502
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发表时间：
1997
期刊：
影响因子：
3.7
通讯作者：
T. Sejnowski
中科院分区：
文献类型：
--
作者：
Akaysha C. Tang;A. Bartels;T. Sejnowski
新皮质神经元在体内是自发活动的，细胞内记录显示，强烈波动的膜电位所产生的不规则的兴奋性和抑制性突触电位的到来。除了这些快速的波动，更缓慢变化的影响，从弥漫性激活的神经调节系统改变皮层神经元的兴奋性，通过调节各种钾电导。特别是，乙酰胆碱，影响学习和记忆，减少缓慢alterhyperpolarization，这有助于尖峰频率适应。我们使用全细胞膜片钳记录的锥体神经元在新皮层切片和计算机模拟显示，首先，当波动的输入被添加到一个恒定的电流脉冲，尖峰频率适应减少的波动幅度增加。高频率，高振幅波动的输入，类似于在体内条件下表现出只有弱尖峰频率适应。第二，卡巴胆碱（一种胆碱能激动剂）的浴应用显著增加了响应于波动输入的放电速率，但最小限度地使尖峰时间移位< 3 ms，这与在体内条件下重复视觉刺激时观察到的尖峰抖动相当。这些结果表明，胆碱能调制可能会保留信息编码在精确的尖峰时间，但不是在interspike间隔，和胆碱能机制以外的那些涉及适应可能有助于显着胆碱能调制的学习和记忆。
Neocortical neurons in vivo are spontaneously active and intracellular recordings have revealed strongly fluctuating membrane potentials arising from the irregular arrival of excitatory and inhibitory synaptic potentials. In addition to these rapid fluctuations, more slowly varying influences from diffuse activation of neuromodulatory systems alter the excitability of cortical neurons by modulating a variety of potassium conductances. In particular, acetylcholine, which effects learning and memory, reduces the slow alterhyperpolarization, which contributes to spike frequency adaptation. We used whole-cell patch-clamp recordings of pyramidal neurons in neocortical slices and computational simulations to show, first, that when fluctuating inputs were added to a constant current pulse, spike frequency adaptation was reduced as the amplitude of the fluctuations was increased. High-frequency, high-amplitude fluctuating inputs that resembled in vivo conditions exhibited only weak spike frequency adaptation. Second, bath application of carbachol, a cholinergic agonist, significantly increased the firing rate in response to a fluctuating input but minimally displaced the spike times by < 3 ms, comparable to the spike jitter observed when a visual stimulus is repeated under in vivo conditions. These results suggest that cholinergic modulation may preserve information encoded in precise spike timing, but not in interspike intervals, and that cholinergic mechanisms other than those involving adaptation may contribute significantly to cholinergic modulation of learning and memory.
影响因子：
2.5
作者：
Reich, DS;Victor, JD;Kaplan, E
通讯作者：
Kaplan, E
影响因子：
2.5
作者：
HASSELMO, ME;BOWER, JM
通讯作者：
BOWER, JM
影响因子：
2.5
作者：
Victor, JD;Purpura, KP
通讯作者：
Purpura, KP