Inflammatory responses of the rabbit eye to prostaglandins

A modified Draize scoring procedure has been used to quantify the vascular effects of prostaglandins on the rabbit eye. Topical application of 100 microgram of PGE1 caused conjunctival redness (erythema due to vasodilatation), swelling (oedema due to increased capillary permeability), discharge, lids closure (decrease in palpebral aperture) and occasionally miosis, though no corneal or iridial damage was detected up to three hours. PGE1 and GE2 produced practically identical dose-related increases in scores for most of the inflammation parameters, though oedema responses were consistently lower after PGE2. The neutral, triethanolamine salt of PGE1 was as inflammatory as PG1 itself. PGF2alpha was 10-50 times less inflammatory than PGE1. It produced relatively greater erythema responses than oedema responses, when compared to PGE1. The novel prostaglandins, 19-OH PGE1 and 19-OH PGE2, recently identified as major prostaglandin constituents of human semen, were respectively 71 and 78 times inflammatory than PGE1. The 19-OH PGEs produced much greater erythema responses, relative to oedema, lids closure or discharge responses.