title: Overexpression of melanopsin in the retina restores visual function in Royal College of Surgeons rats.
abstract: Retinitis pigmentosa (RP) is a pathological condition leading to progressive visual decline resulting from continual loss of photoreceptor cells and outer nuclear layers of the retina. The aim of the present study was to explore whether melanopsin was able to restore retinal function and inhibit its degeneration by acting in a similar manner to channel rhodopsins. Royal College of Surgeons rats, which were used as an animal model of inherited retinal degeneration, were subjected to sub-retinal injection with melanopsin overexpression vector (AV‑OPN4‑GFP). Immunohistochemical and western blot analyses were used to detect the distribution and protein expression of melanopsin in the retina, revealing that melanopsin was gradually reduced with increasing age of the rats, which was due to loss of dendritic axons of intrinsically photosensitive retinal ganglion cells. Animals injected into both eyes were subjected to a behavioral open-field test, revealing that melanopsin overexpression reduced the loss of light sensitivity of the rats. In a flash electroretinography experiment, the b‑wave and response to light flash stimuli at three and five weeks following injection with AV‑OPN4‑GFP were higher compared to those in eyes injected with AV‑GFP (P<0.05). In conclusion, the present study showed that during retinal degeneration, the expression of melanopsin was significantly decreased, while vector-mediated overexpression of melanopsin delayed the loss of visual function in rats.
authors.affiliation: Southwest Hospital/Southwest Eye Hospital, Third Military Medical University, Chongqing 400038, P.R. China.
authors.forename: Mingming
authors.initials: M
authors.lastname: Liu
authors.affiliation: Southwest Hospital/Southwest Eye Hospital, Third Military Medical University, Chongqing 400038, P.R. China.
authors.forename: Jiaman
authors.initials: J
authors.lastname: Dai
authors.affiliation: Southwest Hospital/Southwest Eye Hospital, Third Military Medical University, Chongqing 400038, P.R. China.
authors.forename: Wenyi
authors.initials: W
authors.lastname: Liu
authors.affiliation: Southwest Hospital/Southwest Eye Hospital, Third Military Medical University, Chongqing 400038, P.R. China.
authors.forename: Chongjian
authors.initials: C
authors.lastname: Zhao
authors.affiliation: Southwest Hospital/Southwest Eye Hospital, Third Military Medical University, Chongqing 400038, P.R. China.
authors.forename: Zheng Qin
authors.initials: ZQ
authors.lastname: Yin
mesh_terms: D000818:Animals; D001369:Axons / Q000473:pathology / Q000528:radiation effects; D003712:Dendrites / Q000473:pathology / Q000528:radiation effects; D004596:Electroretinography; D005822:Genetic Vectors / Q000378:metabolism; D008027:Light; D010775:Photic Stimulation; D051381:Rats; D012160:Retina / Q000378:metabolism* / Q000503:physiopathology* / Q000528:radiation effects; D012162:Retinal Degeneration / Q000378:metabolism / Q000503:physiopathology; D012165:Retinal Ganglion Cells / Q000473:pathology / Q000528:radiation effects; D017299:Rod Opsins / Q000378:metabolism*; D014785:Vision, Ocular / Q000528:radiation effects; D000099210:Melanopsin
chemical_list: D017299:Rod Opsins; D000099210:Melanopsin