Malnutrition studies in Macaca mulatta. V. Effect on biochemical and cytochemical composition of major organs

The effects of control, dilute, and low-protein duets on organ development were evaluated in infant rhesus monkeys. Both experimental duets resulted in growth failure of the cerebral hemisphere, lung, liver, kidney, and muscle and, with few exceptions, in their total organ contents of water, protein, lipid, glycogen, DNA, and RNA. Calculation of the various ratios for biochemical indices per mg of DNA indicates that with the exception of increased glycogen:DNA ratios in lung of animals fed the dilute diet, increased lipid:DNA ratios in liver, and reduced glycogen:DNA ratios in muscle of animals fed the low-protein diet, all other biochemical profiles of the cellular populations of organs were comparable to control values. Accordingly, the small organ size and reduced organ content of the various biochemical indices of growth appear primarily due to the reduced cellular populations of these organs. The reduced cellular populations reflect failure of the normal miotic processes of infancy to occur, with or without loss of cells already present at the onset of the malnutrition phase. If no cell loss is involved, it is speculated that normal indices of organ growth may still be possible through the processes of "catch up" growth which accompany nutritional rehabilitation.