Dendritic attenuation of synaptic potentials in the CA1 region of rat hippocampal slices detected with an optical method
Dendritic attenuation of synaptic potentials in the CA1 region of rat hippocampal slices detected with an optical method
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光学法检测大鼠海马切片CA1区突触电位树突状衰减
DOI：
10.1046/j.0953-816x.2001.01550.x
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发表时间：
2001
影响因子：
3.4
通讯作者：
H. Miyakawa
中科院分区：
文献类型：
--
作者：
M. Inoue;Y. Hashimoto;Y. Kudo;H. Miyakawa
我们采用光学方法直接测量海马CA1锥体神经元树突上的快速兴奋性突触后电位（epsp），研究突触电位沿树突传播的方式。用电压敏感荧光染料JPW1114对大鼠海马切片进行染色，用16 × 16光电二极管阵列系统监测光信号。将刺激电极放置在空隙层分子处以激活穿孔纤维，使其与远端根尖树突形成突触接触，或将刺激电极放置在取向层处以诱导CA1锥体细胞基底树突的epsp。光信号的CNQX敏感成分被认为是群体epsp，被分离出来。用光学方法成功地观察了CNQX组分的传输和衰减。在细胞体层，CNQX敏感组分的峰值比输入位点延迟了17.08±1.64 ms。此外，我们还进行了模拟研究，以估计顶端树突的被动膜参数。孔隙层分子刺激后的表观比内轴电阻（Ri）为76.0±4.2 Ω·cm，表观比膜电阻（Rm）为27.8±2.1 kΩ·cm2（假设树突比膜电容cm = 1.6µF/cm2）。这些值与以前报告的值相当。当突触输入施加于取向层时，这些表面被动膜参数不同（高Ri和低Rm），这表明树突膜的不均匀电导或在静息电位附近活跃的电压依赖性电导可能有助于测量到的被动膜特性。
We directly measured fast excitatory postsynaptic potentials (EPSPs) along the dendrites of hippocampal CA1 pyramidal neurons by employing an optical method to study how synaptic potentials spread along the dendrites. Rat hippocampal slices were stained with a fluorescent voltage‐sensitive dye JPW1114 and optical signals were monitored with a 16 × 16 photodiode array system. A stimulating electrode was placed either at stratum lacunosum moleculare to activate perforant fibers that make synaptic contacts to the distal apical dendrites or at stratum oriens to induce EPSPs at the basal dendrites of CA1 pyramidal cells. CNQX‐sensitive components of the optical signals, which were assumed to be population EPSPs, were isolated. Propagation and attenuation of the CNQX components were successfully observed with the optical method. At the cell body layer, the peak of the CNQX‐sensitive component was delayed by 17.08 ± 1.64 ms from the input sites. Additionally we performed a simulation study to estimate the passive membrane parameters of the apical dendrites. Estimated apparent specific internal axial resistance (Ri) following stratum lacunosum moleculare stimulation was 76.0 ± 4.2 Ω·cm and apparent specific membrane resistance (Rm) was 27.8 ± 2.1 kΩ·cm2 (assuming the specific membrane capacitance of dendrites Cm = 1.6 µF/cm2). These values are comparable to those previously reported. When synaptic inputs were applied at stratum oriens, these apparent passive membrane parameters were different (high Ri and low Rm), suggesting that nonuniform dendritic membrane conductance or voltage‐dependent conductances which are active near the resting potential may contribute to the measured passive membrane properties.
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通过阻断大鼠新皮质锥体神经元的电压和 Ca2 依赖性电导来改变从顶端树突传输到体细胞的电流。
DOI：
10.1152/jn.1997.78.1.187
发表时间：
1997
期刊：
Journal of neurophysiology.
影响因子：
--
作者：
Schwindt,PC;Crill,WE
通讯作者：
Crill,WE
影响因子：
56.9
作者：
MAGEE, JC;JOHNSTON, D
通讯作者：
JOHNSTON, D
影响因子：
2.5
作者：
Cook, EP;Johnston, D
通讯作者：
Johnston, D
影响因子：
2.5
作者：
Magee, JC;Carruth, M
通讯作者：
Carruth, M
影响因子：
2.5
作者：
SPRUSTON, N;JAFFE, DB;JOHNSTON, D
通讯作者：
JOHNSTON, D