Uptake of beta-hydroxybutyrate, acetoacetate and glucose by the forearm of the newborn infant.

Forearm muscle metabolism was studied in twelve appropriate for gestational age premature infants suffering from respiratory distress. Arterial blood was obtained by puncture of the radial artery as clinically indicated for measuring oxygen tension, and venous blood samples were taken from the same arm's deep brachial vein. This arrangement allowed to study the arterial-deep venous differences of beta-hydroxybutyrate, acetoacetate and glucose in simultaneously taken blood samples. Net muscular uptakes of beta-hydroxybutyrate and glucose were observed, however, in four studies a virtual net production of acetoacetate was found. The arterial-deep venous concentration differences of both ketone bodies correlated positively with their arterial concentration within the 20 to 120 nanomol/ml range. Such a correlation was not observed in glucose utilization. It is concluded that forearm muscles in the neonate take up ketone bodies and this is in part concentration regulated.