Do catecholamines contribute to the effects of neonatal hypoxia on development of brain and heart? Influence of concurrent alpha-adrenergic blockade on ornithine decarboxylase activity.

Published

Journal Article

Hypoxia in the neonate releases catecholamines from the adrenal medulla, a response which is necessary to survive. This study examines whether a similar dependence exists for the ability of brain and heart tissue to recover from hypoxia-induced damage, as assessed by measurements of ornithine decarboxylase (ODC) activity. Hypoxia at either 1 day or 8 days of age produced a subsequent elevation of brain ODC which persisted for 1 week, a pattern known to be associated with recovery from tissue damage and delayed cellular maturation. Pretreatment of the rats with phenoxybenzamine, an alpha-receptor blocking agent, resulted in attenuation of the long-term ODC response, but did not interfere with effects on the enzyme during the hypoxia itself. In the heart, hypoxia at 8 days of age displayed similar effects, with long-term ODC elevations which were attenuated by phenoxybenzamine. Hypoxia at 1 day of age also produced long-term heart ODC stimulation, but in this case the effect was exacerbated by phenoxybenzamine, an effect consistent with the greater dependence of cardiac tissue on alpha-receptor-mediated responses to hypoxia at that age. These results suggest that alpha-receptor stimulation by catecholamines released during neonatal hypoxia play a role in the metabolic adjustment of brain and heart tissue to damage and may aid in subsequent recovery.

Full Text

Duke Authors

Cited Authors

  • Slotkin, TA; Orband-Miller, L; Queen, KL

Published Date

  • 1987

Published In

Volume / Issue

  • 5 / 2

Start / End Page

  • 135 - 143

PubMed ID

  • 2845716

Pubmed Central ID

  • 2845716

International Standard Serial Number (ISSN)

  • 0736-5748

Language

  • eng

Conference Location

  • England