Purpose: A retinal projection into the dorsal raphe nucleus (DRN), namely, the retino-raphe projection, exists in many species. The @entity35 is one of several species in which a retino-raphe projection has been described; however, the retinal ganglion cell (RGC) types that contribute to this pathway are unknown. Methods: Retrograde tracing via @entity34981 ( @entity34981 ) was used to reveal DRN-projecting RGCs in @entity35 , combined with intracellular injection in vitro, melanopsin immunostaining in whole-mounted retinas, and @entity750 immunostaining to define the DRN. We modified methods of @entity34981 injection into DRN used previously in order to avoid possible contamination with other retinorecipient regions, particularly the superior colliculus (SC). Results: The majority of DRN-projecting RGCs showed alpha-like morphology, and some @entity34981 -positive RGCs were colabeled with melanopsin. Approximately 80% of the total population of @entity34981 -labeled DRN-projecting RGCs was alpha-like cells including ON alpha cells and OFF alpha cells; these alpha-like cells were melanopsin immunonegative. Approximately 10% of the remaining DRN-projecting RGCs were melanopsin immunopositive, in which the M1 subtype of intrinsically photosensitive retinal ganglion cell (ipRGC) provided the dominant projection of ipRGCs into DRN, with only few non-M1 ipRGCs involved. The DRN-projecting ipRGCs could be retrogradely labeled following tracer injection into all rostrocaudal aspects of the DRN. Conclusions: Both conventional RGCs with alpha-like morphology and melanopsin-expressing ipRGCs project into the @entity35 DRN. Approximately 10% of DRN-projecting RGCs were colabeled with melanopsin, and the majority of these were the M1 subtype of ipRGCs. An ipRGC component of the retino-raphe projection may contribute to a sustained light-mediated modulation of DRN @entity750 release.

The Dorsal Raphe Nucleus Receives Afferents From Alpha-Like Retinal Ganglion Cells and Intrinsically Photosensitive Retinal Ganglion Cells in the XXXX .

@entity35 :: ('10116', 'Species') :: ['rat', 'rats'] @entity34981 :: ('286936(Tax:10116)', 'Gene') :: ['CTB', 'cholera toxin subunit B'] @entity750 :: ('MESH:D012701', 'Chemical') :: ['serotonin']
@entity35 :: (10116,Species) :: ['Rat']
