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Developmental differences in myocardial ATP metabolism.

J W de Jong·P W Achterberg
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Abstract

Little is known about postnatal changes in myocardial purine metabolism. We therefore studied how ATP catabolism was affected by hypothermia and ischaemia in neonatal and adult hearts. Hypothermia during ischaemia protected isolated adult and newborn hearts against ATP decline. Reperfusion after normothermic ischaemia resulted in higher ATP levels in newborn hearts with less release of ATP-catabolites. During normoxia adult hearts released mainly urate (80% of total purine release), while newborns released mainly hypoxanthine (64%). During early reperfusion adult and newborn hearts released mainly inosine (50-60%). The very low xanthine oxidase activity in the neonatal heart could be an important factor in the observed ATP preservation during reperfusion.

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Adenosine TriphosphateAgingAnimalsAnimals, NewbornHeartIn Vitro TechniquesKineticsMyocardiumPurinesRatsJournal ArticleResearch Support, Non-U.S. Gov't

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J W de Jong, P W Achterberg. 1987. Developmental differences in myocardial ATP metabolism.. https://doi.org/10.1007/978-3-662-11289-2_12

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