The role of platelets in blood-aqueous barrier breakdown induced by anterior chamber paracentesis in the rabbit.

Anterior chamber paracentesis of the rabbit eye causes disruption of the blood-aqueous barrier, which is characterized by a rapid increase in the albumin and total protein content of the aqueous humor. Prostaglandins appear to be implicated as major mediators in this reaction, since a cyclooxygenase inhibitor, indomethacin, very efficiently prevents protein leakage. When paracentesis was performed in platelet-depleted rabbits (either by transfusion or by treatment with an antiplatelet plasma), the protein content in the aqueous humor did not rise to values observed in normal animals. These data suggest that platelets play some role in the response to paracentesis, a fact in accordance with histological results. In contrast to cyclooxygenase inhibitors, dexamethasone inhibits neither the blood-aqueous barrier breakdown nor prostanoid release from platelets. These data also indirectly indicate the possible role of platelets in triggering the paracentesis reaction in the rabbit.