Changes in lens membrane major intrinsic polypeptide during cataractogenesis in aged Hannover Wistar rats.

Cataracts previously have been shown to occur spontaneously in aged Hannover Wistar rats. The morphology and time course of opacification of these cataracts are very similar to those appearing in the human lens, where it has been previously shown that the major intrinsic polypeptide (MIP26K) of the fiber cell membrane undergoes covalent modification during cataractogenesis. To ascertain possible biochemical similarities between the two cataract systems, antisera were made against synthetic peptides corresponding to the sequence of MIP26K to probe Western blots of lens proteins from transparent versus opaque lenses from normal aged rats. The results of this analysis showed that these antisera can detect the presence of covalent changes occurring in the MIP26K molecule during the development of cortical opacities in the normal aged rat.