Figure 5. Effect of timolol (0.5%, 30 μl) on IOP of conscious Tibetan monkeys. The drug was administered topically at 9 AM (Time 0) onto a randomly assigned eye of each animal, while the contralateral eye received vehicle as control. IOP was monitored at 3, 6, and 24 h later. Error bars represent SEM (n=6). Top Panel: IOP values of both groups. *p<0.05 between the two treatment groups by two-tailed paired Student's t-test. Bottom panel: % IOP change of the timolol group relative to the vehicle control group.