Background Interleukin （IL）-1β may effectively decrease introcular pressure （IOP） when administered by subconjunctival injection in normal rabbit. However, IL-1β is a large molecular agent and an inflammation factor. The aim of this study was to evaluate the penetrability of IL-1β, and the concentrations of both tumor necrosis factor （TNF）-α and IL-6 in the aqueous humor of normal rabbits treated with IL-1β. Methods A total of 170 rabbits were used in the study and were assigned to several different treatment groups as follows： 125 of the rabbits were assigned to two groups. In one group, 33 rabbits were injected subconjunctivally with IL-1β and 39 were injected with saline alone. In the other group, 27 rabbits were given eye drops containing IL-1β （400 ng/ml） and 26 were given saline alone. Aqueous humor （AH） was drawn and the concentration of IL-1β within the fluid measured. The lOP was measured in another six rabbits after administration of eye drops containing IL-1β （400 ng/ml）. A further 20 rabbits were assigned to 3 groups as follows： eight untreated normal controls; six injected subconjunctivally with IL-1β; and six injected subconjunctivally with saline alone. AH was drawn and the concentration of TNF-a in the fluid was measured. Another 19 rabbits were assigned to 3 groups as follows： seven untreated normal controls; and six injected subconjunctivally with IL-1β; and six injected subconjunctivally with saline alone. AH was drawn and the concentration of IL-6 in the fluid measured. Measurement of cytokine concentration was by radio-immunoassay in all cases. Results The IL-1β concentration in the AH was higher in those animals in which it had been administered subconjunctivally （P 〈0.01）. The IL-1β concentration in the AH of the animals given eye drops was almost the same as that in the controls （P 〉0.05）. The administration of IL-1β in the form of eye drops had little effect upon lOP reduction. Lower TNF-α concentrations were seen in the AH after th
PENG Xiao-yanCHEN Feng-huaWANG Ning-liMA Jian-minPing-yu LeeLIU Ke-gaoSteven M Podos
