Jacobson S G, Kemp C M, Narfström K, Nilsson S E
Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami School of Medicine, FL 33101.
Exp Eye Res. 1989 Nov;49(5):843-52. doi: 10.1016/s0014-4835(89)80043-0.
Abyssinian cats with different stages of a slowly progressive autosomal recessively-inherited retinal degeneration were studied with imaging fundus reflectometry (IFR) and electroretinography (ERG). Maps of the visual pigment distribution were made in an area of retina extending from the posterior pole to the midperiphery. Rhodopsin levels in the midperipheral retina of a 6-month-old affected cat (stage of suspected disease) were reduced about 20% relative to the mean normal value. The same cat, tested at 2.5 yr of age (now moderately advanced stage), showed a 60% reduction. A 3-yr-old affected cat (also moderately advanced) had a reduction in rhodopsin of about 60%. There was no measurable rhodopsin in a 7-yr-old affected cat (advanced stage). Rhodopsin regeneration kinetics at the different stages of disease were found to be similar to those of normal cats. The rod ERG b-wave threshold in the 6-month-old cat was elevated by 0.26 log units; at 2.5 yr of age, the threshold was elevated by 0.48 log units. A 0.34 log units threshold elevation was found in the 3-yr-old cat. There was no detectable ERG in the 7-yr-old cat. The relationship between the rod ERG threshold elevations and the rhodopsin levels was close to that expected if the dysfunction was caused by decreased quantal absorption.
利用眼底反射成像（IFR）和视网膜电图（ERG）对患有缓慢进行性常染色体隐性遗传视网膜变性不同阶段的阿比西尼亚猫进行了研究。在从后极延伸至中周部的视网膜区域绘制了视觉色素分布图。一只6个月大的患病猫（疑似疾病阶段）中周部视网膜的视紫红质水平相对于正常平均值降低了约20%。同一只猫在2.5岁时（现为中度进展期）进行测试，视紫红质水平降低了60%。一只3岁的患病猫（也是中度进展期）视紫红质降低了约60%。在一只7岁的患病猫（晚期）中未检测到视紫红质。发现疾病不同阶段的视紫红质再生动力学与正常猫相似。6个月大的猫的视杆细胞ERG b波阈值升高了0.26对数单位；在2.5岁时，阈值升高了0.48对数单位。在3岁的猫中发现阈值升高了0.34对数单位。7岁的猫未检测到ERG。如果功能障碍是由量子吸收减少引起的，视杆细胞ERG阈值升高与视紫红质水平之间的关系接近预期。
