The Emory mouse cataract: increased accumulation of calcium during cataractogenesis

Total calcium and total protein contents have been determined in Emory mouse cataracts from 6 to 19 months of age and also in age-matched Cataract-resistant control lenses. The normal lens calcium is about 0.006 micrograms/mg fresh lens weight; in cataracts the value increases from about 0.02 in beginning cataracts to 0.4 in severe cataracts. Calcium does not increase with age in control lenses. Elevation of calcium levels never precedes initial cataractous changes and is most probably a secondary change. This mouse cataract, unlike human senile cataracts, invariably accumulates calcium and the magnitude is roughly proportional to the severity of cataract. It appears to be a simpler and more homogenous type than human cataract and is therefore more suitable for biochemical studies.