Kern T S, Engerman R L
Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison 53706-1532.
Invest Ophthalmol Vis Sci. 1995 Feb;36(2):490-6.
The suitability of the galactose-fed rat as a model of diabetic retinopathy was examined in nondiabetic rats fed diets enriched with either 30% or 50% galactose for up to 2 years.
Retinal capillaries were examined by light and electron microscopy, and the prevalence or severity of diabetic-like lesions was quantitated.
Histologic evaluation of trypsin digests of retina revealed significantly greater than normal frequencies of pericyte ghosts and acellular capillaries at both 15 and 23 months receiving a 50% galactose diet. Similar lesions were observed in rats receiving a 30% galactose diet for 23 months. Capillary basement membrane thickening, dilated hypercellular capillaries (or intra-retinal microvascular abnormalities), and foci of vascular cells appeared in rats fed 50% galactose, but saccular microaneurysms characteristic of retinopathy in diabetic patients, diabetic dogs, and experimentally galactosemic dogs were not observed. Administration of the aldose reductase inhibitor, Sorbinil, to rats fed 50% galactose resulted in a significant inhibition of cataract and of galactitol accumulation in nerve and blood (by more that 90%) and retina (by 62%), but did not inhibit development of the retinal microvascular lesions.
Two years of galactosemia in rats seems to reproduce only a portion of the lesions characteristic of diabetic retinopathy in patients or dogs. Nevertheless, lesions characteristic of at least the early stages of retinopathy clearly do develop in this galactosemic rat model, and are not restrained by inhibition of retinal polyol accumulation by 62%.
通过给非糖尿病大鼠喂食富含30%或50%半乳糖的饮食长达2年，来检验半乳糖喂养大鼠作为糖尿病视网膜病变模型的适用性。
通过光学显微镜和电子显微镜检查视网膜毛细血管，并对糖尿病样病变的发生率或严重程度进行定量分析。
对视网膜胰蛋白酶消化物的组织学评估显示，在接受50%半乳糖饮食的15个月和23个月时，周细胞鬼影和无细胞毛细血管的频率明显高于正常水平。在接受30%半乳糖饮食23个月的大鼠中也观察到了类似病变。喂食50%半乳糖的大鼠出现了毛细血管基底膜增厚、扩张的高细胞毛细血管（或视网膜内微血管异常）以及血管细胞灶，但未观察到糖尿病患者、糖尿病犬和实验性半乳糖血症犬视网膜病变特有的囊状微动脉瘤。给喂食50%半乳糖的大鼠服用醛糖还原酶抑制剂索比尼尔，可显著抑制白内障以及神经和血液（超过90%）和视网膜（62%）中半乳糖醇的积累，但不能抑制视网膜微血管病变的发展。
大鼠两年的半乳糖血症似乎仅重现了患者或犬糖尿病视网膜病变特征性病变的一部分。然而，在这种半乳糖血症大鼠模型中确实会出现至少视网膜病变早期阶段的特征性病变，并且视网膜多元醇积累62%的抑制作用并不能抑制这些病变的发展。
