THALAMOCORTICAL RESPONSES OF MOUSE SOMATOSENSORY (BARREL) CORTEX INVITRO
THALAMOCORTICAL RESPONSES OF MOUSE SOMATOSENSORY (BARREL) CORTEX INVITRO
复制标题
DOI：
10.1016/0306-4522(91)90333-j
复制
发表时间：
1991-01-01
期刊：
影响因子：
3.3
通讯作者：
CONNORS, BW
中科院分区：
文献类型：
--
作者：
AGMON, A;CONNORS, BW
我们开发了一种新型的小鼠体感前脑切片制剂。 该制剂的独特之处在于，将丘脑腹基底核和感觉运动“桶”皮层包含在 400 μm 厚的切片中，并保留了它们之间的功能连接，并且允许在未染色的活体组织中直接可视化桶系统的各个组件。 通过记录由腹基底核电诱发的皮质场电位的层状分布来证明丘脑皮质连接性。 该剖面的电流源密度分析表明，最大和最早的汇与丘脑皮质末梢的两个已知位点（第四层以及第五层和第六层的交界处）共同延伸。 第四层中的汇可以通过实验分离成突触前起源的一个小的、早期的汇（最有可能是丘脑皮质末端的突触前尖峰齐射）和突触后产生的后来的、更大的汇。 通过绘制在不同第四层记录位点引起反应的皮质下刺激位点，我们得出结论，丘脑到皮质的投射保留了传入神经的一般背腹关系。 细胞内记录的丘脑刺激引起的反应包括（但不限于）单突触兴奋性和双突触抑制性突触后电位。 丘脑到皮质的连接也用轴突荧光示踪剂双十八烷基四甲基吲哚羰花青高氯酸盐进行了绘制。丘脑皮质切片是一个非常适合研究丘脑皮质突触的生理学和药理学以及探索体感皮质突触回路的系统。
We have developed a novel slice preparation of the mouse somatosensory forebrain. This preparation is unique in including both the ventrobasal nucleus of the thalamus and the sensorimotor "barrel" cortex in a 400-mu-m-thick slice with the functional connectivity between them preserved, and in allowing direct visualization of the various components of the barrel system in unstained living tissue. Thalamocortical connectivity was demonstrated by recording the laminar profile of cortical field potentials evoked electrically from the ventrobasal nucleus. Current-source density analysis of this profile showed that the largest and earliest sinks were coextensive with the two known sites of thalamocortical terminals, layer IV and the junction of layers V and VI. The sink in layer IV could be dissociated experimentally into a small, early sink of presynaptic orgin (most probably a presynaptic spike volley in the thalamocortical terminals) and a later, larger sink generated postsynaptically. By mapping the subcortical stimulation sites that elicited a response at different layer IV recording sites we concluded that the thalamus-to-cortex projection preserves the general dorsoventral relationship of the afferents. Intracellularly recorded responses elicited by thalamic stimulation included (but were not limited to) monosynaptic excitatory and disynaptic inhibitory postsynaptic potentials. The thalamus-to-cortex connections were also mapped with the axonal fluorescent tracer dioctadecyl-tetramethylindocarbocyanine perchlorate.The thalamocortical slice is a very suitable system for studying the physiology and pharmacology of the thalamocortical synapse and for exploring the synaptic circuitry of the somatosensory cortex.