Dry eye syndrome model established in rabbits via mitomycin C injection in the lacrimal gland

PURPOSE: To develop a new dry eye syndrome (DES) animal model by injecting mitomycin C (MMC) into the lacrimal glands (LGs) of rabbits evaluated by clinical examinations. MATERIALS AND METHODS: A volume of 0.1 mL of MMC solution was injected in the LG and the infraorbital lobe of the accessory LG of rabbits for DES induction. Twenty male rabbits were separated into three groups, the control group, and different concentration of MMC, (MMC 0.25: 0.25 mg/mL or MMC 0.50: 0.5 mg/mL) were tested. Both MMC-treated groups received MMC twice injection on day 0 and day 7. Assessment of DES included changes in tear production (Schirmer's test), fluorescein staining pattern, conjunctival impression cytology, and corneal histological examination. RESULTS: After MMC injection, no obvious changes in the rabbit's eyes were noted by slit-lamp examination. Both the MMC 0.25 and the MMC 0.5 groups revealed decreased tear secretion after injection, and the MMC 0.25 group showed a continuous decrease in tear secretion up to 14 days. Fluorescent staining showed punctate keratopathy in both MMC-treated groups. In addition, both MMC-treated groups demonstrated decreased numbers of conjunctival goblet cells after injection. CONCLUSION: This model induced decreased tear production, punctate keratopathy, and decreased numbers of goblet cells, which are consistent with the current understanding of DES. Therefore, injecting MMC (0.25 mg/mL) into the LGs is an easy and reliable method to establish a rabbit DES model which can apply in new drug screening.