Metabolic changes in the skin of rats of various ages. Oxygen consumption and uptake of glucose.

1. Parallel determinations of the oxygen consumption by skin slices with glucose or galactose as substrate and of the concentration of DNA of the skin of various ages of rats were carried out to study the metabolic changes of the skin with age. 2. Both the oxygen consumption and the DNA content of the skin decreased rapidly till the attainment of maturity; thereafter the rate of decrease in oxygen consumption was lower whereas the concentration of DNA was constant. The decrease in the oxygen consumption during the early developmental period is thus due to the loss of cells, but the decrease in the older rats may be due to a decline in the activity of the cells of the skin as a result of aging. 3. The uptake of glucose by the skin decreased with increasing age.