Abstract
The effects of intravitreally injected prostaglandins (PGs) and arachidonic acid (AA) on the electrical activity of the retina were studied by monitoring the electroretinogram (ERG) of rabbits. In normal rabbits, intravitreal injection of PGE, PGE2 or AA caused a gradual depression of b-wave amplitude as measured either in low (2 lux) or normal (300 lux) background illumination: up to 15% depression was observed within 1 hr and no recovery was noted during 4 hr of monitoring. The depression of the b-wave amplitude after the intravitreal injection of AA and PGs was similar in time course. Bromcresol green, an inhibitor of PG transport, significantly potentiated the effects of low doses of PGE1 and PGE2 and, to a lesser extent, that of AA. Indomethacin, a known inhibitor of cyclooxygenase activity, prevented the AA-induced, but not the PG-induced depression of the b-wave amplitude. It is concluded that PGs can have a direct effect on the retina and that this region of the eye contains sufficient cyclooxygenase activity to produce pathophysiologically significant amounts of PGs and/or related autacoids.