In vivo passage of albumin from the aqueous humor into the lens

[摘要] Purpose: To determine if albumin, the major protein component of theaqueous humor, passes into the lens in vivo.Methods: Rat albumin was covalently-labeled with Alexa 488fluorophore, purified by gel permeation chromatography, then injectedinto the aqueous chamber of living rats. At 5 min postinjection, lenseswere removed and analyzed by HPLC gel permeation chromatography,confocal microscopy, and immunogold electron microscopy.Results: At 5 min postinjection, HPLC analysis detected measurableamounts of Alexa-labeled albumin in the lens. The results were confirmedby confocal microscopy, which showed passage into epithelial andcortical fiber cells. Immunogold electron microscopy using antibody tothe Alexa fluorophore demonstrated intracellular location of theAlexa-albumin complex.Conclusions: In vivo, significant amounts of albumin pass from theaqueous chamber into cells of the lens, consistent with a possiblephysiological role for this process involving passage of metabolitesinto the lens.

[学科分类] 生物化学/生物物理