方法：将40只雄性C57BL/6小鼠(取右眼为实验眼)用随机数字表法将小鼠分为4组：对照组10只，每次腹腔注射生理盐水0.2mL； 低剂量组、中剂量组、高剂量组各10只为模型组，每次分别腹腔注射浓度为12.5、25、50mg/mL的右旋糖酐铁溶液0.2mL。每3d注射1次，共注射28d。注药后第7、14、28d观察各组小鼠眼表炎症指数、角膜荧光素染色、泪膜破裂时间(BUT)及泪液分泌量(SⅠt)，评估干眼及眼表炎症程度。28d后处死小鼠，取角膜、结膜及泪腺组织，进行HE染色、普鲁士蓝染色以及组织铁检测，评估小鼠炎症反应及铁过载情况； 采用酶联免疫吸附试验(ELISA)检测炎症因子白细胞介素-1β(IL-1β)、肿瘤坏死因子-α(TNF-α)、基质金属蛋白酶-9(MMP-9)的表达情况。

结果：与对照组相比，模型组小鼠出现一系列干眼症状，小鼠眼表炎症指数增高，角膜荧光素染色评分增加，BUT缩短，泪液分泌量减少(均P<0.05)； 模型组小鼠角膜、结膜及泪腺组织均受到不同程度的损伤，各组织眼表铁沉积情况较对照组加重，组织铁含量明显增加(均P<0.01)； 模型组小鼠角膜、结膜及泪腺组织中炎症因子(IL-1β、TNF-α、MMP-9)的含量均高于对照组(均P<0.01)，随着右旋糖酐铁注药时间及浓度增加，小鼠干眼及眼表炎症程度逐渐加重。

结论：腹腔注射右旋糖酐铁可成功建立小鼠铁过载干眼模型，其机制可能与铁过载加重眼表炎症反应有关。

METHODS: A total of 40 male C57BL/6 mice(taking the right eye as the experimental eye)were divided into 4 groups by random number table method: There were 10 mice in the control group, each time by intraperitoneal injection of 0.2mL of normal saline; Low-dose group, middle-dose group and high-dose iron group with 10 mice in each group were the model group. Each time, 0.2mL of iron dextran solution with concentrations of 12.5, 25, and 50 mg/mL was injected intraperitoneally. One injection 3d for a total of 28d. We observed the ocular surface inflammation index, corneal fluorescein staining, tear break-up time(BUT)and Schimer I test(SIt)on the 7, 14 and 28d after injection and evaluated the degree of dry eye and ocular surface inflammation. After 28d, the mice were sacrificed for cornea, conjunctiva and lacrimal glands tissue for HE staining, Prussian blue staining and tissue iron detection, to evaluate the inflammatory reaction and iron overload. The expression of inflammatory factors interleukin-1β(IL-1β), tumor necrosis factor-α(TNF-α)and matrix metallo proteinase-9(MMP-9)were detected by enzyme-linked immunosorbent assay(ELISA).

RESULTS: Compared with the control group, the mice in the model group showed a series of dry eye symptoms, the inflammation index of ocular surface in mice were increased, the score of corneal fluorescein staining increased, the BUT shortened and the amount of tear secretion decreased(all P<0.05). The cornea, conjunctiva and lacrimal gland tissues of the mice were damaged to varying degrees, the iron deposition on the eye surface of the model group was more serious than that of the control group, and the iron content of the tissue was significantly increased than the control group(all P<0.01). The contents of inflammatory factors(IL-1β, TNF-α, MMP-9)in the cornea, conjunctiva and lacrimal gland tissue of the mice in the model group were significantly higher than those of the control group(all P<0.01). With the increase of injection time and concentration of iron dextran, the degree of dry eye and ocular surface inflammation in mice gradually increased.

CONCLUSION: The mouse iron overload dry eye model was successfully established by intraperitoneal injection of iron dextran, the mechanism may be related to the ocular surface inflammation aggravated by iron overload.