S 872419 A, a specific receptor antagonist of peptide leukotrienes, was tested in the early-phase treatment of chemically burned eye (0.25 mol/l sodium hydroxide) of the rabbit. The drug was topically applied 5 times a day in a 1% solution, controls were the untreated opposite eye. Gross and microscopic investigations indicated that S 872419 A inhibits the inflammatory response of the chemically burned anterior eye segment. The parameters of healing considered (epithelial regeneration, corneal clouding and swelling, infiltration with polymorphonuclear leukocytes) suggest inhibition of lipoxygenase-mediated reactions in the tissue. PGF2 alpha levels were the same in aqueous humour of treated and untreated eyes. Further experiments with S 872419 A and other nonsteroidal drugs should improve the anti-inflammatory therapy of the chemically burned eye.

BN 52 021, a specific antagonist of PAF receptors, was tested in the early-phase treatment of chemically burned eyes in 30 rabbits. The local application of BN 52 021 eyedrops-1% (water-soluble preparation, 5 times daily, in comparison with the other eye as a control) led to a visible anti-inflammatory effect (microscopically and macroscopically) of the chemically burned anterior eye segment. There was only a moderate increase of the concentration of PGF2 alpha after the chemical burn. The use of specific PAF antagonists seems to have a real chance for treatment of inflammatory reactions of the anterior eye segment. A combination with other mediator antagonists should be tested in further experiments.