Abstract
Purpose: :
The lacrimal gland is the target of injuries that are ultimately related to dry eye syndrome. The regenerative mechanisms or potentiality of tissue grafting are poorly understood. The aim of the present study was to evaluate the histologic and functional response to lacrimal gland ablation and allogenic transplantation.
Methods: :
Eight-week-old male Wistar rats were divided into three groups submitted to the following operations (n=5/group). In all groups the left eye was the control eye. Group 1 was submitted to partial ablation of the right lacrimal gland, group 2 was submitted to ablation and transplantation of an allogenic lacrimal gland immediately after the gland was removed from age- and sex-matched controls. Group 3 was submitted to right lacrimal gland denervation. After 1 month the animals were anesthetized and evaluated by slit-lamp examination and by the phenol red thread test and tissues were removed and processed for analysis.
Results: :
Direct slit-lamp observation revealed inflammation and corneal vascularization in group 2 and mild to moderate ocular surface damage in groups 1 and 3. In Groups 1 and 3 there was no punctate keratitis or signs of inflammation. Impression cytology did not reveal significant cornea metaplasia in the experimental groups. The mean levels of phenol red thread test did not differ significantly between groups 1 (6.8±1.7 mm), 2 (6.2±1.4 mm), 3 (8.3±1.9 mm) or the controls (7.2± 1.4 mm) (p=0.082). The lacrimal gland weight was 50.3 ± 18.3 mg in group 1, 60.7 ± 8.5 mg in group 2, 107.0 ± 21.38 mg in group 3, and 132.6 ± 15.3mg in the control group (P=0.0023).
Conclusions: :
The present findings indicate that exorbital lacrimal gland removal and lacrimal gland transplantation induce ocular surface inflammation in rats which may result in tears secretion. Overall, our findings offer a model for further studies of lacrimal gland injury and repair.
Keywords: regeneration • lacrimal gland • keratitis