Susceptibility to N-methyl-N-nitrosourea-induced retinal degeneration in different rat strains

• Published in: Journal of Toxicologic Pathology Vol. 29; no. 1; pp. 67 - 71
• Main Authors: Emoto, Yuko, Yoshizawa, Katsuhiko, Kinoshita, Yuichi, Yuki, Michiko, Yuri, Takashi, Tsubura, Airo
• Format: Journal Article
• Language: English
• Published: Japan JAPANESE SOCIETY OF TOXICOLOGIC PATHOLOGY 01.01.2016; The Japanese Society of Toxicologic Pathology; Japan Science and Technology Agency; Japanese Society of Toxicologic Pathology
• Subjects: Atrophy; Cell death; Degeneration; Melanin; Morphometry; N-Methyl-N-nitrosourea; Photoreceptors; Rats; Retina; Retinal degeneration; Rodents; Short Communication; strain difference; N-methyl-N-nitrosourea; retinal degeneration; rats; strain difference
• ISSN: 0914-9198; 1881-915X; 1347-7404
• DOI: 10.1293/tox.2015-0062

To evaluate the potential role of genetic background in the susceptibility to retinal degeneration induced by N-methyl-N-nitrosourea (MNU), female rats of the Sprague-Dawley (SD), Long-Evans (LE) and Copenhagen (CH) strains were administered 50 mg/kg MNU or saline at 7 weeks of age. Retina morphology and morphometric analysis of all rats was performed 7 days after MNU administration. Atrophy of both the peripheral and central outer retina occurred in all rat strains exposed to MNU. Decreased photoreceptor cell ratio and increased retinal damage ratio were observed. The severities of the retinal atrophy were similar among all three rat strains. In conclusion, MNU-induced photoreceptor degeneration developed consistently in all three strains regardless of the absence (SD rats) or presence (LE and CH rats) of melanin in the retina, suggesting that genetic and melanin factors did not affect photoreceptor cell death after MNU.