Harazny Joanna, Scholz Michael, Buder Thomas, Lausen Berthold, Kremers Jan
Department of Ophthalmology, University Hospital Erlangen, University of Erlangen-Nuremberg, 91054, Erlangen, Germany.
Doc Ophthalmol. 2009 Dec;119(3):181-97. doi: 10.1007/s10633-009-9194-5. Epub 2009 Sep 17.
The DBA/2J (D2J) is a genetic mouse model for glaucomatous neurodegeneration because the animals develop anatomical and functional retinal deficits that partially can be correlated with elevated intraocular pressure (IOP). The IOP starts to increase at an age of about 6 months as a result of morphological changes within the anterior eye segment, e.g., pigment dispersion and iris synechiae. The purpose of the present study was to investigate how ERG responses change in individuals at different ages in D2J mice and to compare these changes with normal aging effects in pigmented C57/B6 (B6) mice. IOP was measured in awake, non-sedated D2J and B6 mice with a rebound tonometer. At ages between 2-3 and 10 months, scotopic flash ERGs were measured five times with about 2 months' intervals. In addition, light adapted flicker ERGs were recorded. Our data show that the D2J shows lower flicker ERG responses than the B6 mice already at an age of 2-3 months. Dark adapted flash ERG responses are not decreased at this age. In both mouse strains the ERG responses decrease as a function of age, but there is a stronger decrease in the D2J mice. The data of flicker ERGs suggest the presence of early functional deficits in the D2J retina that possibly have a post-receptoral origin. The scotopic flash ERG reveals a functional deficit that occurs at a later stage and that possibly is IOP dependent. But, the deficits appear at an age at which the IOP is still lower than in the B6 mouse, indicating that other factors play an additional role.
DBA/2J（D2J）小鼠是青光眼性神经退行性变的基因小鼠模型，因为这些动物会出现解剖学和功能性视网膜缺陷，部分缺陷与眼内压（IOP）升高有关。由于眼前节形态学变化，如色素播散和虹膜粘连，IOP在约6个月龄时开始升高。本研究的目的是调查D2J小鼠不同年龄个体的视网膜电图（ERG）反应如何变化，并将这些变化与色素沉着的C57/B6（B6）小鼠的正常衰老效应进行比较。使用回弹眼压计在清醒、未镇静的D2J和B6小鼠中测量IOP。在2 - 3个月至10个月龄之间，每隔约2个月测量5次暗视闪光ERG。此外，还记录了明适应闪烁ERG。我们的数据表明，D2J小鼠在2 - 3个月龄时闪烁ERG反应就比B6小鼠低。在此年龄暗适应闪光ERG反应并未降低。在两种小鼠品系中，ERG反应均随年龄增长而降低，但D2J小鼠的降低更为明显。闪烁ERG数据表明D2J视网膜存在早期功能缺陷，可能起源于感受器后。暗视闪光ERG显示出后期出现的功能缺陷，可能与IOP有关。但是，这些缺陷出现在IOP仍低于B6小鼠的年龄，表明其他因素起了额外作用。
