Kavli Institute for Systems Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway.
Neuron. 2010 Oct 6;68(1):127-37. doi: 10.1016/j.neuron.2010.08.042.
CA1 cells receive direct input from space-responsive cells in medial entorhinal cortex (MEC), such as grid cells, as well as more nonspatial cells in lateral entorhinal cortex (LEC). Because MEC projects preferentially to the proximal part of the CA1, bordering CA2, whereas LEC innervates only the distal part, bordering subiculum, we asked if spatial tuning is graded along the transverse axis of CA1. Tetrodes were implanted along the entire proximodistal axis of dorsal CA1 in rats. Data were recorded in cylinders large enough to elicit firing at more than one location in many neurons. Distal CA1 cells showed more dispersed firing and had a larger number of firing fields than proximal cells. Phase-locking of spikes to MEC theta oscillations was weaker in distal CA1 than in proximal CA1. The findings suggest that spatial firing in CA1 is organized transversally, with the strongest spatial modulation occurring in the MEC-associated proximal part.
CA1 细胞接收来自内嗅皮层（MEC）中空间响应细胞的直接输入，例如网格细胞，以及来自外侧内嗅皮层（LEC）中的更多非空间细胞。由于 MEC 优先投射到 CA1 的近端，毗邻 CA2，而 LEC 仅支配远端，毗邻下托，因此我们想知道空间调谐是否沿着 CA1 的横轴逐渐变化。在大鼠的背侧 CA1 的整个近-远轴线上植入四极管。在足够大的圆柱体中记录数据，以便在许多神经元中的多个位置引发放电。与近端细胞相比，远端 CA1 细胞的放电更加分散，并且具有更多的放电场。与 MECθ 振荡的尖峰相位锁定在远端 CA1 中比在近端 CA1 中弱。这些发现表明 CA1 中的空间放电是横向组织的，最强的空间调制发生在与 MEC 相关的近端部分。
