Effects of Maternal Protein Restriction on the Kidney of the Newborn Young of Rats

Abstract

The effect of maternal protein restriction on the kidney of the young rat was studied. Kidneys were taken from newborn young of rats fed semipurified diets containing 24% or 6% unsupplemented casein as the sole source of protein throughout pregnancy. There are definite morphological and histochemical differences between kidneys from the animals in the control and protein-deficient groups. Kidneys from the protein-restricted animals have fewer and less well-differentiated glomeruli, a greater proportion of connective tissue, and relatively fewer collecting tubules. PAS-stained sections indicate that proximal convoluted tubules are shorter and have fewer convolutions. Acid and alkaline phosphatase activities were reduced in kidneys of protein-deficient young, but no differences were found in the activities of ATPase, nonspecific esterase, or leucine aminopeptidase. Some changes also resemble those reported in kidneys of protein-deficient weanling rats. It is suggested that maternal protein restriction results in both immaturity in development in the kidneys of the young and in pathological changes symptomatic of protein deficiency.