Pupil diameter in normal cats during the pre-treatment (A), treatment (C) and post-treatment (E) phases, and in glaucomatous cats during the pre-treatment (B), treatment (D) and post-treatment (F) phases. Application of latanoprost 0.005% led to significant miosis in the treated eyes of normal cats, with peak effect at 1h. Glaucomatous cats also demonstrated significant miosis in the treated eyes after administration, with peak effect at 2h. Statistically significant differences are indicated as follows: *p<0.05 latanoprost-treated (OD) vs. vehicle-treated control (OS); **p<0.01, treated vs. control; ***p <0.0001, treated vs. control (Paired t-test); ††p<0.01 post- vs. pre-treatment value; ‡p<0.001 post- vs. pre-treatment value (Repeated Measures ANOVA).