Effects of prostaglandins on form deprivation myopia in the chick

Purpose: To investigate the possible role of endogenous prostaglandins in t he development of form deprivation myopia, as well as the effects of exogen ous prostaglandins using atropine as a positive control. Methods: Monocular form deprivation was accomplished by mounting a transluc ent occluder on one eye of 2-3 day old chicks for 1-4 weeks. Ocular occlusi on for 1-2 weeks was used for pharmacological blocking experiments. The axi al length of the eye was measured by ultrasonography, Results: Indomethacin, administered intramuscularly, subconjunctivally or i ntravitreally had no significant effect on myopia development. Exogenous PG E(2), PGF(2 alpha) and latanoprost acid administered subconjunctivally, or topically as isopropyl ester eyedrops had no statistically significant effe ct on the myopia development. However, PGF(2 alpha) significantly (p < 0.01 ) attenuated the development of myopia after intravitreal injection. The ot her two prostaglandins had no statistically significant effect. Conclusions: Endogenous prostaglandins are unlikely to play a significant r ole in the development of form deprivation myopia in time chick. However, P GF(2 alpha) suprisingly seems to retard the development of form deprivation myopia, but only when administered intravitreally. Whether the mechanism o f the myopia retardation is direct or indirect remains unknown.