title: Retino-retinal projection in juvenile and young adult rats and mice.
abstract: Identification of retino-retinal projecting RGCs (ret-ret RGCs) has been accomplished by tracing RGCs in one retina after intravitreal injection of different tracers in the other eye. In mammals, rabbit and rat, ret-ret RGCs are scarce and more abundant in newborn than in adult animals. To our knowledge, ret-ret RGCs have not been studied in mice. Here we purpose to revisit the presence of ret-ret RGCs in juvenile and young adult rats and mice by using retrograde tracers applied to the contralateral optic nerve instead of intravitreally. In P20 (juvenile) and P60 (young adult) animals, the left optic nerve was intraorbitally transected and Fluorogold (rats) or its analogue OHSt (mice) were applied onto its distal stump. P20 animals were sacrificed 3 (mice) or 5 (rats) days later and adult animals at 5 (mice) or 7 (rats) days. Right retinas were dissected as flat-mounts and double immunodetected for Brn3a and melanopsin. Ret-ret RGCs were those with tracer accumulation in their somas. Out of them some expressed Brn3a and/or melanopsin, while other were negative for both markers. In young adult rats, we found 2 ret-ret RGCs displaced to the inner nuclear layer. In both species, ret-ret RGCs are quite scarce and found predominantly in the nasal retina. In juvenile animals there are significantly more ret-ret RGCs (9 ± 3, rats, 13 ± 3 mice) than in young adult ones (5 ± 6 rats, 7 ± 3 mice). Finally, juvenile and young adult mice have more ret-ret RGCs than rats.
authors: Instituto Murciano de Investigación Biosanitaria Hospital Virgen de la Arrixaca (IMIB-Virgen de la Arrixaca), Murcia, Spain; Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia, Murcia, Spain.
authors: F M
authors: FM
authors: Nadal-Nicolás
authors: Instituto Murciano de Investigación Biosanitaria Hospital Virgen de la Arrixaca (IMIB-Virgen de la Arrixaca), Murcia, Spain; Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia, Murcia, Spain.
authors: F J
authors: FJ
authors: Valiente-Soriano
authors: Instituto Murciano de Investigación Biosanitaria Hospital Virgen de la Arrixaca (IMIB-Virgen de la Arrixaca), Murcia, Spain; Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia, Murcia, Spain.
authors: M
authors: M
authors: Salinas-Navarro
authors: Instituto Murciano de Investigación Biosanitaria Hospital Virgen de la Arrixaca (IMIB-Virgen de la Arrixaca), Murcia, Spain; Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia, Murcia, Spain.
authors: M
authors: M
authors: Jiménez-López
authors: Instituto Murciano de Investigación Biosanitaria Hospital Virgen de la Arrixaca (IMIB-Virgen de la Arrixaca), Murcia, Spain; Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia, Murcia, Spain. Electronic address: manuel.vidal@um.es.
authors: M
authors: M
authors: Vidal-Sanz
authors: Instituto Murciano de Investigación Biosanitaria Hospital Virgen de la Arrixaca (IMIB-Virgen de la Arrixaca), Murcia, Spain; Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia, Murcia, Spain. Electronic address: martabar@um.es.
authors: M
authors: M
authors: Agudo-Barriuso
mesh_terms: D000818:Animals; D001369:Axons / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D020221:Optic Nerve Injuries / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D012160:Retina / Q000166:cytology* / Q000378:metabolism; D012165:Retinal Ganglion Cells / Q000166:cytology* / Q000378:metabolism; D017299:Rod Opsins / Q000378:metabolism; D050819:Transcription Factor Brn-3A / Q000378:metabolism; D000099210:Melanopsin
chemical_list: D015415:Biomarkers; D017299:Rod Opsins; D050819:Transcription Factor Brn-3A; D000099210:Melanopsin; C494189:Pou4f1 protein, mouse
keywords: Brn3a; Displaced; Intrinsically photosensitive RGC; Melanopsin; Retino-retinal ganglion cells; Tracing