PREDNISOLONE, PLATELET-ACTIVATING-FACTOR RECEPTOR ANTAGONIST, OR SUPEROXIDE-DISMUTASE REDUCED LEUKOCYTE ENTRAPMENT INDUCED BY INTERFERON-ALPHA IN RETINAL MICROCIRCULATION

Purpose. Interferon (IFN) alpha has been suggested as a possible treat ment fur choroidal neovascularization. However, the pathogenesis of re tinal complications after IFN therapy still is unknown. Previously, we have shown that IFN alpha induced leukocyte entrapment in retinal mic rocirculation. The current study was designed to determine if leukocyt e entrapment can be reduced by the agents that modulate leukocyte-endo thelial adherence. Methods. Interferon alpha was administered intraven ously in rats. Simultaneously, prednisolone (PSL), platelet-activating factor receptor antagonist (CV-6209), or superoxide dismutase (SOD) w as given to the rats. Leukocyte dynamics were observed with acridine o range (AO) digital fluorography, which uses a nuclear fluorescent dye of AO and scanning laser ophthalmoscopy. The number of trapped leukocy tes in each group was assessed with a personal computer-based image an alysis. Results. Interferon alpha induced leukocyte entrapment in reti nal microcirculation and increased leukocyte adherence to the vessel w alls. The simultaneous administration of PSL, CV-6209, or SOD inhibite d leukocyte adherence to the venous walls and significantly reduced th e number of trapped leukocytes. Conclusions. Acridine orange digital f luorography was helpful to quantitate leukocyte-endothelial interactio ns in retinal microcirculation. The results suggested that increased l eukocyte adherence after IFN alpha administration was reduced signific antly by PSL, CV-6209, or SOD. These agents may be useful to prevent I FN-induced microcirculatory disturbances.