Related Experiment Video
Updated: Jan 6, 2026
Ex Vivo and In Vivo Animal Models for Mechanical and Chemical Injuries of Corneal Epithelium
Published on: April 6, 2022
Effect of silver nitrate solution on corneal epithelial barrier function in rabbits
Masamichi Fukuda1, Takeshi Kiyoi2, Shun Takeda1
1Department of Ophthalmology, Kanazawa Medical University, Ishikawa, Japan.
Purpose:
Some preservatives in eye drops induce corneal epithelial damage. Diquafosol sodium, a dry eye treatment drug released in 2022, contains silver nitrate as a preservative. This study examined the effects of diquafosol sodium ophthalmic solution and silver nitrate solution on the barrier function of corneal epithelial cells in rabbit eyes.
Patients And Methods:
The 14 rabbits included in the study were divided into 7 eye drop treatment groups (4 eyes per group): (1) 3% diquafosol (Diquas) without silver nitrate; (2) 3% Diquas LX containing silver nitrate; (3) 3% Diquas LX without silver nitrate; (4) 0.01% silver nitrate; (5) 0.1% silver nitrate; (6) 1% silver nitrate; and (7) saline. Electrical corneal resistance (CR) was measured using a CR-measuring device (CRD) at 30, 60, and 120 minutes after the final instillation, and CR% was calculated. Corneal epithelial damage was evaluated using fluorescein staining 120 minutes after the final instillation.Corneal tissue obtained 120 minutes post-instillation was fixed in 4% paraformaldehyde, permeabilized, and blocked. Zonula occludens-1 protein, which constitutes tight junctions between epithelial cells, was visualized using whole-mount immunohistochemical staining. To examine the expression of ZO-1 in corneal epithelial cells, photographs of the outermost layer of the cornea were taken.
Results:
CR in the Diquas LX group 1 (containing silver nitrate) reached its peak value (114.2 ± 7.1%) 60 minutes after the final instillation, which was comparable to that in the 0.1% silver nitrate group (117.2 ± 17.6%) and significantly higher than that in the Diquas group 3 (without silver nitrate) (98.8 ± 5.8%; P < 0.05). Zonular occludens-1 protein was localized in a continuous linear pattern at the boundary between epithelial cells in all three Diquas groups.
Conclusions:
Diquas LX eye drops containing silver nitrate significantly increased CR compared to Diquas eye drops without silver nitrate and improved corneal barrier function. Silver nitrate as a preservative may have contributed to this effect.
