Cataract formation following limited amino acid intake during gestation and lactation

Female rats were fed defined diets limiting in one or more of certain amino acids and with or without vitamin E throughout gestation and lactation. Deficits of tryptophan, phenylalanine/tyrosine, or methionine/cystine reduced the body weight of progeny to about 50% or less of normal but only low tryptophan was cataractogenic. When total dietary amino acids were 12.4%, a low (65 mg%) level of tryptophan resulted in 34% incidence of cataract if vitamin E was simultaneously withheld. Elevation of total amino acids to 24.8% while maintaining tryptophan at 65 mg% caused 70 or 90% incidence of nuclear lens opacities in the presence or absence, respectively, of vitamin E. Maternal dietary amino acid imbalance was also associated with a 50% decrease in lens insoluble (membrane) proteins in the progeny independent of dietary vitamin E or the occurrence of opacities.