Effects of theophylline on adenosine-induced respiratory depression in the preterm rabbit.

The adenosine agonist N6-phenylisopropyladenosine (PIA) was given intraperitoneally to preterm rabbit neonates (29 days gestational age). 1 mg i.p. induced a marked respiratory depression and irregular breathing which could be prevented or antagonized by administration of theophylline. The results indicated a central nervous site of action and it is hypothesized that central adenosine overactivity may have a pathophysiological significance for the irregular breathing or apnea of prematurity sometimes seen in the human neonate.