Differential metabolism and leakage of protein in an inherited cataract and a normal lens cultured with ouabain

Ocular lenses in Nakano mice showed marked changes in synthesis, degradation and leakage of protein during cataractogenesis. The cataract-associated changes included the differential lowering of crystalline synthesis, the cleavage of crystallin polypeptides to lower molecular weight forms and the leakage of crystallins from cultured lenses. Ouabain treatment of normal lenses induced these alterations, suggesting that changes in the intracellular levels of Na+ and K+ affect the anabolism and catabolism of protein during cataract formation. 35S-methionine was used during the course of the experiments as a method of protein identification. (author)