Endothelin-1 and intraocular inflammation in pigmented rabbit eyes

Abstract

We assessed the function of Endothelin-1 (ET-1) in the development of anterior chamber inflammation in pigmented rabbit eyes. After the injection of ET-1 solution (10−13, 10−11, 10−9, or 10−7 M, diluted with 300 μL of artificial aqueous humor) into the anterior chamber, the aqueous protein concentration (APC) increased significantly in a dose-dependent fashion. Peak effects were observed 1–2 hours posttreatment. The APC returned to normal 12 hours after the injection. Pretreatment with antiprostaglandin agents, topical indomethacin, or intravenous diclofenac sodium suppressed the increase in APC. In an endotoxin-induced experimental uveitis model, the ET-1 concentration in the aqueous humor was significantly higher than in normal controls, as was the plasma ET-1 level. These results suggest that ET-1 is an important mediator in ocular inflammatory reactions via arachidonic acid cascade.