title: Retinofugal projections in the mouse.
abstract: The laboratory mouse is increasingly a subject for visual system investigation, but there has been no comprehensive evaluation of this species' visual projections. Here, projections were visualized and mapped following intraocular injection of cholera toxin B subunit. Tissue was processed using standard procedures applied to 30 μm free-floating sections with diaminobenzidine as the chromogen. The mouse retina projects to ~46 brain regions, including 14 not previously described in this species. These include two amygdaloid nuclei, the horizontal limb of the diagonal band, the paraventricular hypothalamic nucleus, several visual thalamic nuclei, the paranigral nucleus, several pretectal nuclei, and the dorsal cortex of the inferior colliculus. Dense retinal patches were also observed in a narrow portion of the ipsilateral intermediate layer of the superior colliculus. The superior fasciculus of the accessory optic tract, which innervates the medial terminal nucleus, was also determined to be a terminal zone throughout its length. The results are compared with previous descriptions of projections from mouse intrinsically photoreceptive retinal ganglion cells, and with data from the hamster, Nile grass rat, and laboratory rat. The retinal projection patterns are similar in all four species, although there are many differences with respect to the details. The specific visual functions of most retinorecipient areas are unknown, but there is substantial convergence of retinal projections onto regions concerned with olfaction and audition.
authors.affiliation: Department of Psychiatry, Stony Brook University Medical Center, Stony Brook, NY, 11794-8101; Graduate Program in Neuroscience, Stony Brook University Medical Center, Stony Brook, NY, 11794-8101.
authors.forename: Lawrence P
authors.initials: LP
authors.lastname: Morin
authors.forename: Keith M
authors.initials: KM
authors.lastname: Studholme
mesh_terms: D000818:Animals; D001931:Brain Mapping; D002772:Cholera Toxin / Q000378:metabolism; D007839:Functional Laterality; D020646:Intralaminar Thalamic Nuclei / Q000378:metabolism / Q000502:physiology*; D051379:Mice / Q000033:anatomy & histology*; D008810:Mice, Inbred C57BL; D012160:Retina / Q000033:anatomy & histology* / Q000378:metabolism; D012165:Retinal Ganglion Cells / Q000378:metabolism; D017299:Rod Opsins / Q000378:metabolism; D014795:Visual Pathways / Q000378:metabolism / Q000502:physiology*; D000099210:Melanopsin
chemical_list: D002772:Cholera Toxin; D017299:Rod Opsins; D000099210:Melanopsin
keywords: JAX:000664; auditory; melanopsin; nonimage forming; olfactory; retinorecipient; subcortical; visual system