PREMATURE infants excrete much less creatine in the urine than young full-term infants, whose urinary creatine may amount to approximately 40% of the total creatinine.1
The present investigation was planned to clarify some of the mechanisms accounting for this difference. Studies were made on the effect of feeding creatine or its precursors on the excretion of creatine, creatinine, and guanidoacetic acid by these infants. In other observations, blood levels of creatine and creatinine were determined in relation to urinary excretion. Analyses were also made of the creatine content of muscle at various stages of fetal development. The results suggest that the premature infant stores or utilizes creatine to a greater extent than does the full-term infant.
Observations were made on boy babies who were given partially skimmed cow's milk-carbohydrate feeding mixtures of approximately 110 to 130 calories per kilogram of body weight per day with added vitamins A,