Prostaglandin biosynthesis in the rat lens

Abstract

Rat lens microsomal preparations possess the capability of converting exogenous arachidonic acid into prostaglandins (PG) E2 and F2 alpha. The low, yet measurable prostaglandin biosynthetic capacity of the lens microsomes was demonstrated by radioimmunoassay (RIA) and by separation of radiolabeled products after incubation with high specific activity U-14 [C]-arachidonic acid. Maximal formation of radioimmunoassayable PGE2 and PGF2 alpha was measured after a 15-min incubation at 37 degrees C with approximately 0.5 mg protein. Prostaglandin biosynthesis was inhibited by the nonsteroidal anti-inflammatory agents aspirin (IC50 = 52 microM) and indomethacin (IC50 = 20 microM). These results unequivocally demonstrate prostaglandin biosynthesis in rat lens.