Haverkamp Silke, Ghosh Krishna K, Hirano Arlene A, Wässle Heinz
Max-Planck-Institut für Hirnforschung, D-60528 Frankfurt/Main, Germany.
J Comp Neurol. 2003 Jan 20;455(4):463-76. doi: 10.1002/cne.10491.
With the ever-growing number of transgenic mice being used in vision research, a precise knowledge of the cellular organization of the mouse retina is required. As with the cat, rabbit, rat, and primate retinae, as many as 10 cone bipolar types and one rod bipolar type can be expected to exist in the mouse retina; however, they still have to be defined. In the current study, several immunocytochemical markers were applied to sections of mouse retina, and the labeling of bipolar cells was studied using confocal microscopy and electron microscopy. By using antibodies against the neurokinin-3 receptor NK3R; the plasma membrane calcium ATPase1 (PMCA1); and the calcium (Ca)-binding proteins CaB1, CaB5, caldendrin, and recoverin, three different OFF-cone bipolar cells could be identified. One type of ON-cone bipolar cell was identified through its immunoreactivity for CaB5 and PMCA1. Rod bipolar cells, comparable in morphology to those of other mammalian retinae, expressed protein kinase Calpha and CaB5. It was also shown that putative OFF-cone bipolar cells receive light signals through flat contacts at the cone pedicle base, whereas ON-cone bipolar signaling involves invaginating contacts. The distribution of the kainate receptor subunit GluR5 was studied by confocal and electron microscopy. GluR5 was expressed at flat bipolar cell contacts; however, it appears to be involved with only certain types of OFF-cone bipolar cells. This suggests that different bipolar cell types receive their light signals through different sets of glutamate receptors.
随着用于视觉研究的转基因小鼠数量不断增加，需要精确了解小鼠视网膜的细胞组织。与猫、兔、大鼠和灵长类动物的视网膜一样，预计小鼠视网膜中存在多达10种视锥双极细胞类型和1种视杆双极细胞类型；然而，它们仍有待确定。在本研究中，将几种免疫细胞化学标记物应用于小鼠视网膜切片，并使用共聚焦显微镜和电子显微镜研究双极细胞的标记。通过使用抗神经激肽-3受体NK3R、质膜钙ATP酶1（PMCA1）以及钙（Ca）结合蛋白CaB1、CaB5、钙树突蛋白和恢复蛋白的抗体，可以识别出三种不同的视锥OFF双极细胞。通过其对CaB5和PMCA1的免疫反应性鉴定出一种视锥ON双极细胞。视杆双极细胞在形态上与其他哺乳动物视网膜的视杆双极细胞相似，表达蛋白激酶Cα和CaB5。还表明，假定的视锥OFF双极细胞通过视锥小足基部的扁平接触接收光信号，而视锥ON双极信号传导涉及内陷接触。通过共聚焦显微镜和电子显微镜研究了海人藻酸受体亚基GluR5的分布。GluR5在扁平双极细胞接触处表达；然而，它似乎仅与某些类型的视锥OFF双极细胞有关。这表明不同类型的双极细胞通过不同组的谷氨酸受体接收光信号。
