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.
Journal Article (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
International Standard Serial Number (ISSN)
- 0736-5748
Digital Object Identifier (DOI)
- 10.1016/0736-5748(87)90059-1
Language
- eng
Conference Location
- United States