EARLY DECREASE IN NO-RELEASE BY THE RETIN A AFTER EXPERIMENTAL BRANCH-VENOUS OCCLUSION

Purpose We present hereby some results indicating that there is a sign ificant decrease in the release of NO by the retina immediately after branch-venous occlusion (BVO). Methods Using an NO microprobe we measu red (NO) in the preretinal vitreous of miniature pigs before and two h ours aRer bvo. Conventional and electronic microscopy were performed o n the affected retina. Results At the retinal surface (NO) was reduced to 25% of the previous value two hours after BVO, at the same time si gnificative oedema of the inner retina was observed. Conclusions Immed iately after BVO there is a significative decrease in the amount of NO released by the affected retina, parallel to the first evidences of a n oedema of the inner retinal layers.