Effect of rebamipide ophthalmic suspension on the success of lacrimal stent intubation

Rebamipide promotes lacrimal duct epithelial cell survival via protecting barrier function

Nasolacrimal duct obstruction (NLDO) is thought to be due to inflammation and fibrosis of lacrimal duct epithelial cells (LDECs). Here we investigated the effect of rebamipide, a drug that is used for the protection of the mucosa and the treatment of gastritis and gastroduodenal ulcers, on LDECs, both in vitro and in vivo. In this study, LDECs were cultured from rabbit lacrimal duct tissues, and the barrier function of LEDCs was examined in vitro via transepithelial electrical resistance (TER) measurement, with or without interleukin (IL)-6 and/or rebamipide. For the in vivo examination, benzalkonium chloride (BAC) was injected into the rabbit lacrimal ducts, followed by the application of rebamipide or a placebo vehicle alone. The results of the in vitro examination revealed a significant decrease in TER in the group treated with IL-6 alone compared with the placebo-vehicle group (p < 0.05) and the group treated with IL-6 and rebamipide (p < 0.01). The results of the in vivo examination revealed that the infiltration of neutrophils under the basement membrane and the disruption of tight junction proteins with BAC injection and rebamipide attenuates the disturbance of tissue construction. These results suggest that rebamipide protects LDECs via an anti-inflammatory effect and preserves the barrier function of those cells.

Pathological changes of the nasolacrimal duct in rabbit models of chronic dacryocystitis: correlation with lacrimal endoscopic findings

PURPOSE

The aim of this study was to explore the pathological changes of the nasolacrimal duct in rabbits with experimentally induced obstructive dacryocystitis in correlation with lacrimal endoscopic findings.

METHODS

The rabbit model of obstructive dacryocystitis was created by injecting 0.15 ml of self-curing resin into the lacrimal duct. The control group received 0.15 ml of normal saline. Within 16 weeks after the obstructive, lacrimal endoscopy and pathological examination of the nasolacrimal duct were conducted at different time points of 1, 2, 4, 8, and 16 weeks.

RESULTS

In the control group, lacrimal endoscopy revealed pink and smooth mucosa; and the pathological analysis revealed an epithelial layer that was composed of superficial columnar cells and a deep basal epithelial layer. The experimental rabbits showed clinical manifestations of obstructive dacryocystitis a week after the injection of self-curing resin. At weeks 1 and 2, the lacrimal endoscopy showed mucosal hyperemia and hemorrhagic spots on the nasolacrimal duct; and the pathological features included epithelial cell swelling and inflammatory cell infiltration. At weeks 4 and 8, the experimental group showed alternatively red and white mucosa under the lacrimal endoscopy, and the pathological features included proliferative epithelium accompanied by papillary hyperplasia. At week 16, the experimental group showed pale and coarse mucosa and white membrane-like layer covering the mucosal surface, and the pathological features included epithelial necrosis, squamous metaplasia, and sub-epithelial fibrosis.

CONCLUSION

The mucosa of the nasolacrimal duct showed different pathological features at different time points after lacrimal duct obstruction, which was well correlated with the endoscopic findings. It is possible to predict the pathological stages by the endoscopic observation in NLOD patients.