[High myopia and retinal ultrastructure of albino guinea-pigs].
OBJECTIVE
To explore the relationship between melanin synthesis and the congenital high myopia of albino guinea-pigs.


METHODS
Twelve albino guinea-pigs and 12 pigmented guinea-pigs of 220~250 grams (aged 5~6 weeks) were chosen at random. The eyes were examined with retinoscopy, A-scan ultrasonography and vernier caliper. The retinal structures were examined with light and electronic microscope.


RESULTS
The diopter was -19.17 D in albino guinea-pigs and +0.63 D in pigmented guinea-pigs on average. Compared with the pigmented guinea-pigs, the axial dimensions of the albino guinea-pigs were elongated. There was significant difference between the albino guinea-pigs and the pigmented guinea-pigs. The retinal thickness, pigment granules and membrane disc of the outer segment of the visual cells decreased in the albino guinea-pigs, and the membrane disc space became narrow. The normal retinal thickness, plenty of pigment granules , membrane disc and wide membrane disc space could be observed in the pigmented guinea-pigs.


CONCLUSIONS
Albino guinea-pigs have high myopia, and pigmented guinea pigs have light hyperopia. There are structural differences in the retina between albino guinea-pigs and pigmented guinea-pigs. The abnormity of albino guinea-pigs provides optical foundation for its high myopia.
Wang
Jie-Yue
JY
Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China.
Liu
Shuang-Zhen
SZ
Wei
Xin
X
Wu
Xiao-Ying
XY
Tan
Xing-Ping
XP
D000417:Albinism / Q000150:complications*; D000818:Animals; D006168:Guinea Pigs; D008543:Melanins / Q000096:biosynthesis*; D008855:Microscopy, Electron, Scanning; D009216:Myopia / Q000151:congenital / Q000209:etiology / Q000378:metabolism*; D011897:Random Allocation; D012160:Retina / Q000378:metabolism* / Q000473:pathology / Q000648:ultrastructure; D012880:Skin Pigmentation
D008543:Melanins