IN-VITRO EFFECT OF FUROSEMIDE ON THE CHEMILUMINESCENCE OF POLYMORPHONUCLEAR NEUTROPHILS IN PRETERM INFANTS

We tested the hypothesis that the phagocytic activity of polymorphonuc lear neutrophils (PMNs) of neonates is more sensitive to furosemide (F U) in vitro than that of adults. Phagocytosis was monitored by chemilu minescence of PMNs in cord blood of full-term (n = 10) and preterm (n = 8) neonates in the presence of 0, 6, 9, and 13 mu g/ml of FU. Venous blood from adults (n = 10) was used for comparison. Random motility a nd chemotaxis were also determined in the three groups. The peak chemi luminescence of PMNs in preterm neonates was significantly decreased a t a FU concentration of either 6, 9, or 12 mu g/ml when compared to fu ll-term infants. In contrast, no difference was observed between full- term infants and adults. Random motility and chemotaxis were comparabl e in all groups, regardless of the FU concentration. The results of th is study suggest that preterm infants may be more sensitive to FU, as indicated by the adverse effect of this drug on chemiluminescence acti vity of their PMNs, in vitro.