Time course for prostaglandin synthesis by rabbit lens during endotoxin-induced ocular inflammation

Three hours to 14 days following the intravitreal injection of 10 ng of E. coli endotoxin into the vitreal chamber of one eye of the New Zealand white rabbit, ocular inflammation was evaluated by clinical and biochemical criteria and prostaglandins were measured in the intraocular fluids and in the incubation medium of the intact lens. Increased synthesis of PGE2 was detected for lenses from inflamed eyes beginning at 18 h post-endotoxin injection. Lenticular PGE2 synthesis remained above control levels for the duration of the time course. Lenses also exhibited increased PGF2 alpha synthesis, which began at 18 h and returned to control levels by day 7. At the times of peak production, aqueous humor PGE2 concentration correlated with lenticular PGE2 synthesis and with aqueous humor leukocyte number. No correlations were found for lenticular PGE2 vs. cell number, or vitreous humor PGE2 vs. aqueous humor PGE2. These results suggest that during ocular inflammation, aqueous humor PGE2 may be derived, at least in part, from the lens and leukocytes.