Differential response dynamics of corticothalamic glutamatergic synapses in the lateral geniculate nucleus and thalamic reticular nucleus
Differential response dynamics of corticothalamic glutamatergic synapses in the lateral geniculate nucleus and thalamic reticular nucleus
复制标题
DOI：
10.1016/j.neuroscience.2005.11.012
复制
发表时间：
2006-01-01
期刊：
影响因子：
3.3
通讯作者：
Godwin, DW
中科院分区：
文献类型：
--
作者：
Alexander, GM;Fisher, TL;Godwin, DW
皮质丘脑反馈通路向丘脑网状核和外侧膝状体核提供兴奋性突触输入。我们研究了兴奋性突触后电流引起的皮质丘脑刺激丘脑网状核和外侧膝状体核的视觉部门，比较这些神经元的反应，刺激他们共同的输入途径。使用全细胞膜片钳记录在雪貂丘脑切片，我们比较了单个兴奋性突触后电流衰减动力学，突触前谷氨酸释放动力学通过配对脉冲易化和响应皮质丘脑串刺激。我们发现单个丘脑网状核的兴奋性突触后电流明显比外侧膝状体反应更尖锐。平均丘脑网状核兴奋性突触后电流衰减常数（tau）为4.9 +/- 0.5 ms，而平均外侧膝状体核兴奋性突触后电流T值为11.8 +/- 0.8 ms。突触前释放动力学作为测量成对刺激的反应是保守的丘脑网状核和外侧膝状体核之间。然而，促进反应列车刺激显着不同的核团。外侧膝状体反应比丘脑网状核反应（达到兴奋性突触后电流I振幅的223.1 ± 44.0%）显示出更大的易化作用（达到兴奋性突触后电流I振幅的842.9 ± 76.4%）。这些数据表明，虽然皮质丘脑通路产生兴奋性突触后电流在丘脑网状核和外侧膝状体核，其他因素独特地影响在每个核的输入功能整合。(c)2005由Elsevier Ltd代表IBRO出版。
The corticothalamic feedback pathway provides excitatory synaptic input to both the thalamic reticular nucleus and the lateral geniculate nucleus. We studied excitatory postsynaptic currents elicited from corticothalamic stimulation in the visual sector of the thalamic reticular nucleus and the lateral geniculate nucleus to compare the response of these neurons to stimulation of their common input pathway. Using whole cell patch clamp recordings in ferret thalamic slices, we compared single excitatory postsynaptic current decay kinetics, presynaptic glutamate release dynamics through paired pulse facilitation and responses to corticothalamic train stimulation. We found that single thalamic reticular nucleus excitatory postsynaptic currents were significantly sharper than lateral geniculate nucleus responses. The mean thalamic reticular nucleus excitatory postsynaptic current decay constant (tau) was 4.9 +/- 0.5 ms, while the mean lateral geniculate nucleus excitatory postsynaptic current T value was 11.8 +/- 0.8 ms. Presynaptic release dynamics as measured by responses to paired stimuli were conserved between the thalamic reticular nucleus and lateral geniculate nucleus. However, facilitating responses to train stimulation were markedly different between nuclei. Lateral geniculate nucleus responses showed proportionately larger facilitation (reaching 842.9 +/- 76.4% of excitatory postsynaptic current I amplitude) than thalamic reticular nucleus responses (reaching 223.1 +/- 44.0% of excitatory postsynaptic current I amplitude). These data indicate that while the corticothalamic pathway produces excitatory postsynaptic currents in both the thalamic reticular nucleus and lateral geniculate nucleus, other factors uniquely affect the functional integration of the inputs in each nucleus. (c) 2005 Published by Elsevier Ltd on behalf of IBRO.