Urinary biogenic amines in idiopathic apnea of prematurity.

Urinary biogenic amines were measured in 22 preterm infants of less than 36 weeks' gestational age. Fifteen of these infants had idiopathic apnea. Although levels of urinary dopa were not significantly different, dopamine, norepinephrine and epinephrine were all significantly lower in the infants with apena. It is proposed that apnea of prematurity may be related to an immaturity of catecholamine-producing pathways, leading to inadequate physiologic responses to hypoxia, with resulting accentuation of central respiratory depression. Alternatively, urinary biogenic amines may be a reflection of some unrelated process occurring elsewhere in the body or a depletion of catechol stores resulting from the apnea itself.