Renal effects of anoxia and nephrotoxic drugs assessed by urinaryα-1-microglobulin (α1m) and N-acetyl-glucosaminidase (NAG) in premature infants † 839

Room-Air Resuscitation Causes Less Damage to Heart and Kidney than 100% Oxygen

“…Moreover, the intensity of the asphyctic insult correlated with the urinary excretion of NAG (7,8). Although it has been postulated that immature renal cells are more resistant to hypoxia than mature cells and recover more rapidly after reoxygenation (36), our asphyctic subjects showed significantly higher levels of NAG in urine in the first 2 d as compared with nonasphyxiated infants in the control group.…”

“…In previous studies, newborn infants presented elevated urinary concentrations of NAG after birth anoxia (8). Moreover, the intensity of the asphyctic insult correlated with the urinary excretion of NAG (7,8).…”

“…Thus, urine samples collected during the first 48 h after birth revealed elevated concentrations of NAG in asphyxiated newborns. NAG is a specific enzyme present in the proximal tubular cells of the kidney, and its appearance in urine is a highly sensitive marker of tubular cell necrosis (6)(7)(8).…”

“…dase (NAG), an enzyme present in the lysosomes of the proximal tubular cells, not filtered through the glomerulus but rapidly cleared from the circulation by the liver (6) and especially reliable for detecting tubular damage after neonatal anoxia (7,8).…”