Valiente-Soriano Francisco J, García-Ayuso Diego, Ortín-Martínez Arturo, Jiménez-López Manuel, Galindo-Romero Caridad, Villegas-Pérez Maria Paz, Agudo-Barriuso Marta, Vugler Anthony A, Vidal-Sanz Manuel
Departamento de Oftalmología, Facultad de Medicina, Campus de Espinardo, Universidad de Murcia, e Instituto Murciano de Investigación Biosanitaria-Hospital Clínico Universitario Virgen de la Arrixaca (IMIB-ARRIXACA) Murcia, Spain.
Department of Ocular Biology and Therapeutics, UCL-Institute of Ophthalmology London, UK.
Front Neuroanat. 2014 Nov 20;8:131. doi: 10.3389/fnana.2014.00131. eCollection 2014.
Here we have studied the population of intrinsically photosensitive retinal ganglion cells (ipRGCs) in adult pigmented and albino mice. Our data show that although pigmented (C57Bl/6) and albino (Swiss) mice have a similar total number of ipRGCs, their distribution is slightly different: while in pigmented mice ipRGCs are more abundant in the temporal retina, in albinos the ipRGCs are more abundant in superior retina. In both strains, ipRGCs are located in the retinal periphery, in the areas of lower Brn3a(+)RGC density. Both strains also contain displaced ipRGCs (d-ipRGCs) in the inner nuclear layer (INL) that account for 14% of total ipRGCs in pigmented mice and 5% in albinos. Tracing from both superior colliculli shows that 98% (pigmented) and 97% (albino) of the total ipRGCs, become retrogradely labeled, while double immunodetection of melanopsin and Brn3a confirms that few ipRGCs express this transcription factor in mice. Rather surprisingly, application of a retrograde tracer to the optic nerve (ON) labels all ipRGCs, except for a sub-population of the d-ipRGCs (14% in pigmented and 28% in albino, respectively) and melanopsin positive cells residing in the ciliary marginal zone (CMZ) of the retina. In the CMZ, between 20% (pigmented) and 24% (albino) of the melanopsin positive cells are unlabeled by the tracer and we suggest that this may be because they fail to send an axon into the ON. As such, this study provides the first evidence for a population of melanopsin interneurons in the mammalian retina.
在此，我们研究了成年有色和白化小鼠中内在光敏性视网膜神经节细胞（ipRGCs）的数量。我们的数据表明，尽管有色（C57Bl/6）和白化（瑞士）小鼠的ipRGCs总数相似，但其分布略有不同：在有色小鼠中，ipRGCs在颞侧视网膜更为丰富，而在白化小鼠中，ipRGCs在上侧视网膜更为丰富。在这两种品系中，ipRGCs都位于视网膜周边，在Brn3a(+)RGC密度较低的区域。这两种品系在内核层（INL）中也都含有移位的ipRGCs（d-ipRGCs），在有色小鼠中占ipRGCs总数的14%，在白化小鼠中占5%。从双侧上丘进行追踪显示，ipRGCs总数的98%（有色）和97%（白化）被逆行标记，而黑视蛋白和Brn3a的双重免疫检测证实，在小鼠中很少有ipRGCs表达这种转录因子。相当令人惊讶的是，将逆行示踪剂应用于视神经（ON）可标记所有ipRGCs，但不包括d-ipRGCs的一个亚群（分别在有色小鼠中占14%，在白化小鼠中占28%）以及位于视网膜睫状缘区（CMZ）的黑视蛋白阳性细胞。在CMZ中，20%（有色）至24%（白化）的黑视蛋白阳性细胞未被示踪剂标记，我们认为这可能是因为它们未能将轴突发送到ON中。因此，本研究为哺乳动物视网膜中存在一群黑视蛋白中间神经元提供了首个证据。
