The topography of cone photoreceptors in the retina of a diurnal rodent, the agouti (Dasyprocta aguti)
The topography of cone photoreceptors in the retina of a diurnal rodent, the agouti (Dasyprocta aguti)
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DOI：
10.1017/s095252380808098x
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发表时间：
2009-03-01
影响因子：
1.9
通讯作者：
De Lima, Silene Maria A.
中科院分区：
文献类型：
--
作者：
de Farias Rocha, Fernando Allan;Ahnelt, Peter K.;De Lima, Silene Maria A.
密度分布。本文研究了昼夜活动无节毛蚤Dasyprocta aguti视网膜的视锥类型和镶嵌规律。长波敏感的（L-）和短波敏感的（S-）锥检测抗体对各自的锥视蛋白。L-和S-锥被发现代表约90和10%的锥人口，分别。没有证据表明，L-和S-视蛋白的共同表达在agrectones。L锥密度最高，Lip为14，000/mm（2），沿着水平视条纹位于视神经背侧约2-3 mm处，L锥分布显示背腹不对称，腹侧（约10，000/mm（2））密度高于背侧（约4000/mm（2））视网膜区域。这种L-锥拓扑结构与小脑的神经节细胞拓扑结构相似。在视网膜中央区域，S-视锥细胞的峰值密度为1500-2000/mm 2，但不形成视觉条纹。它们的分布也显示出背腹不对称性，在视网膜背侧区域的密度约为600/mm（2），腹侧区域的密度约为1000/mm（2）。通过密度恢复轮廓分析来评估锥阵列的图案化。在评价的所有偏心率下，S-锥镶嵌的填充效率低于L-锥镶嵌。视杆细胞密度从周边的47，000个/mm 2到中央视网膜的64，000个/mm 2不等，视杆细胞与视锥细胞的比例为4：1-9：1。相对较低的杆密度和高锥比例出现很好地适应了昼夜的生活方式的agglomerus。
The presence, density distribution. and mosaic regularity of cone types were studied in the retina of the diurnal agouti, Dasyprocta aguti. Longwave-sensitive (L-) and shortwave-sensitive (S-) cones were detected by antibodies against the respective cone opsins. L- and S-cones were found to represent around 90 and 10% of the cone population, respectively. There was no evidence for L- and S-opsin coexpression in agouti cones. L-cone densities were highest, Lip to 14,000/mm(2), along a horizontal Visual streak located about 2-3 mm dorsal to the optic nerve, and the L-cone distribution showed a dorsoventral asymmetry with higher densities in ventral (about 10,000/mm(2)) than in dorsal (about 4000/mm(2)) retinal regions. This L-cone topography parallels the agouti's ganglion cell topography. S-cones had a peak density of 1500-2000/mm(2) in the central retinal region but did not form a visual streak. Their distribution also showed a dorsoventral asymmetry with densities around 600/mm(2) in dorsal and around 1000/mm(2) in ventral retinal regions. The patterning of cone arrays was assessed by the density recovery profile analysis. At all eccentricities evaluated, the S-cone mosaic less efficiently packed than the L-cone mosaic. Rod densities ranged from 47,000/mm(2) in peripheral to 64,000/mm(2) in central retina,and rod:cone ratios were 4:1-9:1. The comparatively low rod density and high cone proportion appear well adapted to the diurnal lifestyle of the agouti.