The Effect of Bromocriptine on the Inhibition of Eyeball Growth at Various Concentration in Myopic Chicken Model

ABSTRACT

The authors examined the effect and concentration dependency of bromocriptine on the inhibition of axial length elongation in the experimentally induced myopic chicken. Two day-old white Leghorn chicken was monocularly deprived of form vision by lid suture. We measured the axial length of chicken's eye by ultrasonography at 2 day, 2 week, 4 week, and 6 week following repeated ophthalmic dosing beginning at 2 day. The first group was instilled with 0.1 cc of Tris buffer solution, whereas the second, third, and fourth groups were instilled with 0.1cc of 0.01 %, 0.02%, 0.04% bromocriptine solution respectively. All solutions were instilled twice daily for 6 weeks. In the inhibition of axial length elongation, the third group (0.02% bromocriptine) was most effective at 2 week (p<0.05), whereas the second group (0.01% bromocriptine) was most effective at 4 and 6 week (p<0.05). In summary, the axial length elongation of eyeball was effectively retarded by bromocriptine with the best efficacy at 0.02% in short-term dosing while at 0.01% in long-term dosing.