Endotoxin-induced ocular inflammation increases prostaglandin E2 synthesis by rabbit lens

Twenty-four hours after the intravitreal injection of 0.1-100 ng of Escherichia coli endotoxin into one eye of the New Zealand white rabbit, lenses from the inflamed eyes synthesized significantly more prostaglandin E2 (PGE2) than their contralateral, control lenses at all doses of endotoxin greater than 0.1 ng. PGE2 elevations were also seen in the aqueous and vitreous humors from inflamed eyes. Lenses did not synthesize 6-keto-PGF1alpha (a stable metabolite of PGI2). Incubation of untreated lenses with 1 microgram ml-1 of endotoxin for 24 h did not increase PGE2 production. These results indicate that rabbit lens can synthesize PGE2, that this synthesis is significantly increased 24 hr after the intravitreal infusion of E. coli endotoxin, and that this increased PGE2 synthesis is most likely not due to a direct action of endotoxin on the lens.