DECREASED AQUEOUS-FLARE REACTION TO REPEATED APPLICATIONS OF PROSTAGLANDIN E(2) TO THE CORNEA IN PIGMENTED RABBITS

To evaluate the effect of single or repeated topical applications of p rostaglandin E(2) (PGE(2)) to the cornea on the blood-aqueous barrier, we have measured the extent of flare in the anterior chamber of rabbi t eyes at various time intervals. PGE(2) was applied to the cornea for 4 min with the use of a glass cylinder in pigmented rabbits. Aqueous flare was measured by a laser flare cell meter. The flare intensity fo llowing the second application of 25 or 50 mu g/ml of PGE(2) was small er than that following the first application. When 50 mu g/ml of PGE(2 ) was applied every day for 6 days, the flare intensity decreased sign ificantly day by day. After consecutive applications of 10 mu g/ml of PGE(2) at hourly intervals, flare intensity increased up to 3 h, remai ned elevated from 3 to 5 h, and decreased thereafter. Repeated applica tions of 10 mu g/ml of PGE(2), every hour for 14 h every Monday, signi ficantly decreased flare intensity week by week. Weekly applications o f 50 mu g/ml of PGE(2) did not change flare intensity. This study indi cates that the extent of the breakdown of the blood-aqueous barrier in the rabbit eye, as measured by the development of flare in the anteri or chamber, is reduced with repeated PGE(2) application.