Expression Of Matrix Metalloproteinase In Rabbit Dry Eye Model

Objective: To investigate the expression patterns of collagenase MMP-1 and gelatinase MMP-9 in the rabbit corneal tissues of dry eye model of at different periods and to elucidate the functions of MMPs in the pathological progresses of the dry eye.Methods: The dry eye model was established on the right eyes of 30 rabbits, after ablating the corresponding lacrimal gland, the tertiary eyelid and the Harder's gland. The SIT test and corneal fluorescein staining were used to evaluate the inner situations of the eyes at different time points (Day 0, 3, 5, 7, 14, 21 and 28) of the model. The pathological changes of corneal tissues of 15 rabbits on day 14 and day 28 were observed with HE staining,and the expression of MMP-1 and MMP-9 were analysised with immunohistochemistry respectively.Results: The mean ShirmerⅠtest value of untreated rabbit eyes was (16.4±3.8) mm. However the Shirmer l test value was keeping decreasing after the surgery and became stable within 10 mm after 7 days of operation. It is significant different when comparing the Shrimer 1 test value between day 3, 5, 7, 14, 21, 28 days and untreated control eyes. The corneal fluorescein staining was significantly higher in the treated rabbit eyes than that of the untreated control eyes. Optical observation revealed apparent abnormal change of corneal tissue in the established model at day 14 and 28. Interestingly, there was a high degree of correlation between the expression of MMP-1 and MMP-9, which increased significantly with the progression of dry eye and positively correlated with the severity of it.Conclusions: MMP-1 and MMP-9 are involved in the pathological progresses of dry eye model.