[The effects of transcorneal administration of prostaglandin E2 on rabbit eyes]

The pharmacologic effects of prostaglandin E2 (PGE2) on the anterior ocular segment were investigated. PGE2 was administered with a glass cylinder attached to the cornea in concentrations ranging from 0.05 to 500 micrograms/ml. The intraocular inflammatory reaction was assessed according to the changes in the anterior chamber flare, ocular tension, and components of the aqueous humor. We also performed experiments designed to inhibit the reactions induced by PGE2 using anti-inflammatory agents. The PGE2 elicited a single peak reaction in the anterior chamber flare, which recovered after several hours, and a transient elevation in the ocular tension in the early stage after PGE2 administration. Quantitative analysis of these two reactions revealed that both were dependent on the dose of PGE2 administered. The concentrations of ascorbic acid and glutathione, particularly that of the reduced form of the latter, were transiently reduced in the aqueous humor. The anterior chamber flares were suppressed by agents that inhibit arachdonic acid metabolism. These findings suggest that the metabolism of arachdonic acid becomes newly activated as a result of stimulation by PGE2 of extrinsic origin.