Effect of aminophylline on the respiratory depressant action of intravenous adenosine in neonatal rabbits.

We administered intravenous adenosine to 11 neonatal rabbits. Adenosine depressed respiration in 10 of 11 rabbits. For the group as a whole the adenosine-induced respiratory depression was highly significant (p less than 0.001). After aminophylline administration to the same animals the respiratory effect of intravenous adenosine was abolished in 3 animals. In 7 animals the effect of adenosine was reversed and respiratory stimulation was observed. After aminophylline adenosine produced a significant (p less than 0.001) increase in respiration in the group studied. The alteration of responses to intravenous adenosine by aminophylline in neonatal rabbits is similar to the effect of aminophylline on respiratory responses to hypoxia in neonates. Such an effect of aminophylline and other methylxanthines on adenosine actions, possibly central in site may explain their beneficial effect in the treatment of apnoea in the human neonate.