The effect of prenatal protein-calorie malnutrition on kidney development in the rat.

Our studies show that prenatal protein deprivation has a long-term (if not permanent) effect on kidney morphology in the young and effects on renal function that persist at least to the end of weaning. Since animals are still alive and growing, we might ask whether this has any real physiological significance. At this point, it is important to mention that 50% of the young born of protein-deprived dams in these studies did not survive more than 3 d. Those animals that were the subject of the study of postnatal kidneys were presumably less affected. We do not know the extent to which compromised renal function contributed to neonatal death in the others. These results can be extrapolated to other species only with great caution, since the rat kidney is relatively immature at birth. It is probable that increased postnatal feeding has a more beneficial effect on these rapidly developing tissues than it would have in species in which the kidneys are more mature at birth. Yet, kidney function did not reach the control level in spite of improved postnatal nutrition. Compromised renal function in the more mature kidneys of other species may be less amenable to postnatal recovery and--at the very least--leave the kidneys less able to respond to postnatal stress factors.