ABSTRACT
@#【Objective】To provide a rabbit model for dry eye using a dry environment induced by Controlled Drying System.【Methods】Twenty-four male New Zealand rabbits were used in the experiment. They were randomly divided into control group and dry group，each one with 12 rabbits. The dry group was randomly housed in Controlled Drying System（CDS）for 14 days. The relative humidity，airflow and temperature were kept at（22±4）%，3~4 m/s and（23~25）℃， respectively. The control group were fed in a normal environment where relative humidity，airflow and temperature were kept at 60%~70%，0.2 m/s and（23~25）℃. The Schirmer test，corneal fluorescein staining，conjunctival lissamine green staining were performed during the experimental process on days 0，3，7，and 14. On the last day，the rabbits were euthanized and the eye tissues were made into paraffin-cut sections. After staining，we evaluated the corneal epithelial thickness and goblet cell number in the conjunctiva using light microscopy. MUC5AC in the conjunctival epithelium was detected by immunofluorescence. The apoptosis level changes on the ocular surface were evaluated using Caspase- 3 by immunohistochemistry. 【Results】 Decreased tear production ，increased corneal fluorescein staining and increased conjunctival lissamine green staining were found on days 3，7，and 14 in the dry group compared with the control group（P < 0.001）. Corneal epithelial thickness of control group and dry group were （58.0±7.2）μ m and（47.8±7.6）μ m ，which showed corneal epithelial thickness of dry group was decreased（P＜0.05）. Goblet cells in the conjunctiva of control group and dry group were 15 ± 4 and 10 ± 2，which showed goblet cells of dry group was decreased（P＜0.01）. The expression of MUC5AC（consistent with goblet cells deficiency） was also reduced. Caspase- 3 was highly expressed on the corneal epithelium in the dry group. IOD/field of control group and dry group were（17±2）% and（20±2）%（P＜0.01）.【Conclusions】 Dry environment can make rabbits have pathological changes of dry eye on ocular surface epithelium. This dry eye model of rabbit caused by Controlled Drying System would be an effective tool to study the pathogenesis of dry eye.