Abstract
We investigated age-related changes of aqueous humor protein in male, W istar-strain and Ihara cataract f-strain (ICR) rats, using two dimensional electrophoresis with silver staining. In this study we took a system using capillary isoelectric focusing for first dimension separation and polyacrylamide gradient slab gel for second dimension electrophoresis. A 5pl sample of aqueous humor was analyzed. The staining patterns of aqueous humor proteins were almost the same in the two strains. Albumin and Immunoglobulin G (IgG) in aqueous humor were detected by immunoblotting and transferrin (TF) was separated by electrophoresis with purified TF. Albumin was the major aqueous humor protein. Albumin and IgG levels increased with aging, but no increase of TF was observed. In ICR rats, protein concentration in aqueous humor was greater than in W istar strain rats, and larger molecular weight proteins, such as IgG and TF, appeared earlier. This suggests that IgG and TF are actively transported into the aqueous humor and may also be produced around the anterior chamber. It seems likely that IgG and TF are important to changes of the blood-aqueous barrier with aging and cataractogenesis.
