RESUMO
Cultured porcine retinal pigment epithelial cells release superoxide, measured as superoxide dismutase (SOD)-suppressible reduction of cytochrome C, and SOD-suppressible luminol-dependent chemiluminescence. Latex beads stimulated a significant release of superoxide that reached 82 nmol/mg protein in the first 15 min and declined thereafter. Formation of an insoluble blue formazan following reduction of nitroblue tetrazolium histochemically demonstrated that superoxide was released over the region of the cell vicinal to the bead. Dioctanoylglycerol, a synthetic, cell-permeating activator of protein kinase C, also elicited a rapid release of superoxide from RPE cells. This study emphasizes the need to characterize the mechanisms by which superoxide is generated, whether its release is regulated, and how toxicity is prevented in vivo.
Assuntos
Epitélio Pigmentado Ocular/metabolismo , Superóxidos/biossíntese , Animais , Ácidos Araquidônicos/farmacologia , Células Cultivadas , Diglicerídeos/farmacologia , Microesferas , Nitroazul de Tetrazólio , Epitélio Pigmentado Ocular/citologia , Superóxido Dismutase/farmacologia , Suínos , Acetato de Tetradecanoilforbol/farmacologia , Fatores de TempoRESUMO
Multiple myeloma is a serious and fatal condition with various ocular manifestations. In two of these cases, pathologic findings included opaque ciliary body cysts, a ciliochoroidal effusion, retinal microaneurysms and hemorrhages, and detachment of both the sensory retina and the retinal pigment epithelium. In one case, a recanalized thrombus within a retrolaminar vein and direct continuity of a superonasal retinal detachment with a large pars plana cyst was observed. The proteinaceous material in the anterior chamber, ciliary body cysts, choroid and ciliary body, subretinal, and subretinal pigment epithelial areas was identified as immunoprotein using an immunoperoxidase technique.