To evaluate the immediate effects of 3% diquafosol ophthalmic solution on tear MUC5AC concentration and corneal wetting property in rabbit eyes.

Six New Zealand white rabbits were used in the present study. Fifteen minutes after instilling 50 µL of 3% diquafosol into the right eye of each rabbit and 50 µL of saline into the left eye, corneal wetting property, tear MUC5AC concentrations and the area of periodic acid-Schiff (PAS)-stained conjunctival goblet cells were evaluated under general anesthesia using conjunctival impression cytology. Corneal wetting property was evaluated by measuring the duration from when the image of the microscopic light beam was clear on the corneal surface immediately after blinking to when the image began to blur.

The mean time of corneal wetting property was 86.40 (± 17.90) seconds in the diquafosol group and 49.00 (± 6.35) seconds in the control group. There was a significant difference between the two groups ( p = 0.043). The mean concentration of tear MUC5AC was significantly higher in the diquafosol group (18.21 ± 1.52 ng/mL) than the control group (12.75 ± 1.82 ng/mL; p = 0.028). Conjunctival impression cytology showed the area of PAS-stained conjunctival goblet cells was significantly lower in the diquafosol group (23.17 ± 0.05%) than the control group (32.49 ± 0.08%; p = 0.028).

Immediately after instilling 3% diquafosol, corneal wetting property improved significantly. Also tear MUC5AC concentration, which was released from conjunctival goblet cells increased compared to saline.