Oxygen consumption in platelets of newborn infants before and after stimulation by thrombin.

The authors compared the oxygen consumption in platelets from the umbilical cord blood of 36 healthy newborn infants with that of 27 adult subjects, before and after thrombin addition (1.67 U/ml). Oxygen consumption at rest was 6 mumol/10(9)/min in adult control platelets and 5.26 in newborn infants. The burst in oxygen consumption after thrombin addition was 26.30 mumol/10(9)/min in adults and 24.90 in infants. Dinitrophenol did not inhibit the burst of O2 consumption in platelets in 8 out of 10 newborn infants, while the same concentration caused a decrease in 9 out of 10 adult subjects. Deoxyglucose inhibited the burst in O2 consumption in newborn infant and adult platelets by about 50%. KCN at the concentration of 10(-4) M completely inhibited basal oxygen consumption but did not completely inhibit the burst after thrombin. At the concentration of 10(-3) M, it inhibited both basal O2 consumption and the burst in infants and adult subjects.