Recurrent connection patterns of corticostriatal pyramidal cells in frontal cortex
Recurrent connection patterns of corticostriatal pyramidal cells in frontal cortex
复制标题
DOI：
10.1523/jneurosci.0252-06.2006
复制
发表时间：
2006-04-19
影响因子：
5.3
通讯作者：
Kawaguchi, Y
中科院分区：
文献类型：
--
作者：
Morishima, M;Kawaguchi, Y
皮质纹状体锥体细胞在额叶皮质中是异质性的。在这里，我们展示了大鼠额叶皮质中的皮质纹状体神经元亚群根据它们的皮质下靶点选择性地相互联系。利用成对的逆行标记细胞记录，我们研究了两种投射细胞类型之间的突触连接：投射到桥脑[皮质桥(CPN)细胞]的投射细胞，通常有侧支投射到纹状体；投射到纹状体两侧但不投射到桥脑[交叉皮质纹状体(CCS)细胞]的投射细胞。这两种类型在形态上是不同的，就其顶端簇状结构而言。CCS细胞的树突形态与其在皮质内的体细胞深度相关。CCS细胞之间有相互的突触联系，也向CPN细胞提供突触输入。然而，很少发现从CPN到CCS细胞的连接，即使成对地显示CCS到CPN的连接。此外，CCS细胞优先支配其他CCS细胞的基底树突，但同时接触CPN细胞的基底和顶端树突。突触反应的幅度与接触部位的数目有一定的相关性。在CCS-CCS连接中，EPSC波幅与联系次数的比率趋于较大。因此，我们的数据表明，这两种不同树突形态的皮质纹状体细胞在突触连接中表现出方向性和区域依赖性的偏好。
Corticostriatal pyramidal cells are heterogeneous in the frontal cortex. Here, we show that subpopulations of corticostriatal neurons in the rat frontal cortex are selectively connected with each other based on their subcortical targets. Using paired recordings of retrogradely labeled cells, we investigated the synaptic connectivity between two projection cell types: those projecting to the pons [corticopontine (CPn) cell], often with collaterals to the striatum, and those projecting to both sides of the striatum but not to the pons [ crossed corticostriatal (CCS) cell]. The two types were morphologically differentiated in regard to their apical tufts. The dendritic morphologies of CCS cells were correlated with their somatic depth within the cortex. CCS cells had reciprocal synaptic connections with each other and also provided synaptic input to CPn cells. However, connections from CPn to CCS cells were rarely found, even in pairs showing CCS to CPn connectivity. Additionally, CCS cells preferentially innervated the basal dendrites of other CCS cells but made contacts onto both the basal and apical dendrites of CPn cells. The amplitude of synaptic responses was to some extent correlated with the contact site number. Ratios of the EPSC amplitude to the contact number tended to be larger in the CCS to CCS connection. Therefore, our data demonstrate that these two types of corticostriatal cells distinct in their dendritic morphologies show directional and domain-dependent preferences in their synaptic connectivity.