The cone pedicle, a complex synapse in the retina
The cone pedicle, a complex synapse in the retina
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DOI：
10.1016/s0896-6273(00)00011-8
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发表时间：
2000-07-01
期刊：
影响因子：
16.2
通讯作者：
Wässle, H
中科院分区：
文献类型：
--
作者：
Haverkamp, S;Grünert, U;Wässle, H
猕猴视网膜中的视锥蒂是视锥光感受器的突触末梢，与数百个突触后树突相连。利用光镜和电子显微镜，我们发现在每个锥体蒂下有双极细胞和水平细胞的树突层状分布。叠加的是三层谷氨酸受体（GluR）聚集体，包括在桥粒样连接处聚集的谷氨酸受体的新层。它们很可能是水平细胞树突上的突触后密度。GABAA和GABA受体聚集在双极细胞树突上，呈窄带状分布在锥体蒂下方。锥体蒂释放的谷氨酸和水平细胞树突释放的GABA不仅通过直接突触接触起作用，而且通过扩散到适当的受体。
Cone pedicles, the synaptic terminals of cone photoreceptors, are connected in the macaque monkey retina to several hundred postsynaptic dendrites. Using light and electron microscopy, we found underneath each cone pedicle a laminated distribution of dendritic processes of bipolar and horizontal cells. Superimposed were three strata of glutamate receptor (GluR) aggregates, including a novel layer of glutamate receptors clustered at desmosome-like junctions. They are, most likely, postsynaptic densities on horizontal cell dendrites. GABAA and GABA, receptors are aggregated on bipolar cell dendrites in a narrow band underneath the cone pedicle. Glutamate released from cone pedicles and GABA released from horizontal cell dendrites act not only through direct synaptic contacts but also (more so) through diffusion to the appropriate receptors.