Dacheux R F, Raviola E
J Neurosci. 1982 Oct;2(10):1486-93. doi: 10.1523/JNEUROSCI.02-10-01486.1982.
The light responses, morphology, and connections of horizontal cells (HCs) were studied in the retina of the rabbit using intracellular recordings and the injection of visible markers. Two types of HCs were identified, axonless and axon-bearing HCs. Axonless HCs and the somatic end of axon-bearing HCs respond to white light of varying intensity with graded hyperpolarizations; both display a transient superimposed on the sustained hyperpolarization at stimulus initiation and a small rod aftereffect at the cessation of high intensity stimuli. Anatomically, both are connected to cones, but their responses also suggest rod influence. Both summate stimuli from a retinal area which is much larger than their respective fields. However, only axonless HCs transfer a fluorescent, low molecular weight dye to adjoining, homologous cells. The axon terminal of axon-bearing HCs has response properties different from those of the cell body: the transient at stimulus initiation is absent; furthermore, at high levels of illumination, the rod aftereffect becomes equal in amplitude to the primary hyperpolarization. Anatomically, it is connected to rods, but its responses also suggest cone influence. Its receptive field approximates in diameter its anatomical spread and it does not transfer fluorescent dye to its neighbors.
利用细胞内记录和可见标记物注射技术，对兔视网膜中的水平细胞（HCs）的光反应、形态和连接进行了研究。鉴定出了两种类型的水平细胞，即无轴突水平细胞和有轴突水平细胞。无轴突水平细胞和有轴突水平细胞的胞体末端对不同强度的白光产生分级超极化反应；两者在刺激开始时均表现出叠加在持续超极化上的瞬态反应，在高强度刺激停止时表现出小的视杆细胞后效应。在解剖学上，两者均与视锥细胞相连，但其反应也表明受视杆细胞影响。两者都对来自比各自视野大得多的视网膜区域的刺激进行总和。然而，只有无轴突水平细胞能将一种荧光低分子量染料转移到相邻的同源细胞。有轴突水平细胞的轴突终末具有与胞体不同的反应特性：刺激开始时没有瞬态反应；此外，在高光照水平下，视杆细胞后效应的幅度与初级超极化相等。在解剖学上，它与视杆细胞相连，但其反应也表明受视锥细胞影响。其感受野直径与其解剖学分布相近，且不将荧光染料转移到其相邻细胞。
