Permeability of abnormal blood-retinal barriers in rat phototoxic retinopathy: a clinicopathologic correlation study using fluorescent markers.
Phototoxic retinopathic rats were studied by vitreous fluorophotometry (VF) and histofluorescence microscopy using NaFl and FITC-Dextran molecules of selected molecular sizes as blood-retinal barrier permeability determinants. Retinopathic rats had significantly higher VF values than normal rats at a 35 mg/kg NaFl dosage; detectable levels were not obtained with 3.5 mg/kg NaFL nor with FITC-Dextrans. However, as demonstrated by histofluorescence microscopy, NaFl and FITC-Dex 3 molecules readily passed the abnormal BRB tissues to enter neural retina and vitreous space whereas FITC-Dex 20, 40, 70 and 150 molecules did not, except under certain circumstances. These studies indicate a barrier defect of both the retinal vessels and RPE is responsible for the in vivo demonstrated permeability abnormality.
D000818:Animals; D002199:Capillary Permeability; D003911:Dextrans; D016650:Fluorescein-5-isothiocyanate / Q000031:analogs & derivatives*; D005452:Fluoresceins; D008856:Microscopy, Fluorescence; D010783:Photometry / Q000379:methods; D051381:Rats; D012160:Retina / Q000032:analysis; D012164:Retinal Diseases / Q000503:physiopathology*; D012969:Sodium Fluoride; D014822:Vitreous Body / Q000032:analysis
D003911:Dextrans; D005452:Fluoresceins; C015219:fluorescein isothiocyanate dextran; D012969:Sodium Fluoride; D016650:Fluorescein-5-isothiocyanate