低等脊椎动物视网膜中水平细胞上不同的光感受器信号之间的相互作用(英文)

NEURAL INTERACTION OF PHOTORECEPTOR SIGNALS FED FORWARD ONTO HORIZONTAL CELLS IN LOWER VERTEBRATE RETINAS

许多实验证据表明在低等脊椎动物视网膜中 ,水平细胞上不同的光感受器信号之间存在着广泛的相互作用。这种相互作用 ,依赖于光感受器和水平细胞之间的突触连接以及突触前和突触后神经元活动的过程及相对状态 ,可以导致信号之间的相互增强或者相互抑制。此外 ,水平细胞上的光感受器信号之间的相互作用似乎受到包括来自视网膜近端及远端的多个突触回路的调控。谷氨酸、γ-氨基丁酸、甘氨酸和多巴胺等多种神经递质及它们的类似物也都参与此过程的调节。

In lower vertebrate retinas, the neural interactions of various photoreceptor inputs fed forward onto horizontal cells (HCs) have been the subject of intensive study. It has been shown that the interactions can be either positive or negative, which is dependent on specific wiring between photoreceptors and HCs, as well as the status and history of pre and post synaptic neuron activities. Additionally, it appeared that the interactions of photoreceptor signals on horizontal cells involved polysynaptic pathways, which consisted of both distal and proximal retinal neurons. The neurotransmitters (glutamate, γ aminobutyric acid (GABA), glycine, dopamine) and their analogues were found effective in modulating the processes. The present article aims to review the basic phenomena of signal interactions and the possible underlying mechanisms involved.