Document Detail


Perinatal history of hypoxia leads to lower vascular pressures and hyporeactivity to angiotensin II in isolated lungs of adult rats.
MedLine Citation:
PMID:  11191361     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The most dramatic changes in pulmonary circulation occur at the time of birth. We hypothesized that some of the effects of perinatal hypoxia on pulmonary vessels are permanent. We studied the consequences of perinatal exposure to hypoxia (12 % O2 one week before and one week after birth) in isolated lungs of adult male rats (approximately 12 weeks old) perfused with homologous blood. Perfusion pressure-flow relationship was tilted towards lower pressures in the perinatally hypoxic as compared to the control, perinatally normoxic rats. A non-linear, distensible vessel model analysis revealed that this was due to increased vascular distensibility in perinatally hypoxic rats (4.1 +/- 0.6 %/mm Hg vs. 2.3 +/- 0.4 %/mm Hg in controls, P = 0.03). Vascular occlusion techniques showed that lungs of the perinatally hypoxic rats had lower pressures at both the pre-capillary and post-capillary level. To assess its role, basal vascular tone was eliminated by a high dose of sodium nitroprusside (20 microM). This reduced perfusion pressures only in the lungs of rats born in hypoxia, indicating that perinatal hypoxia leads to a permanent increase in the basal tone of the pulmonary vessels. Pulmonary vasoconstrictor reactivity to angiotensin II (0.1-0.5 microg) was reduced in rats with the history of perinatal-hypoxia. These data show that perinatal hypoxia has permanent effects on the pulmonary circulation that may be beneficial and perhaps serve to offset the previously described adverse consequences.
Authors:
V Hampl; J Bíbová; J Herget
Publication Detail:
Type:  In Vitro; Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Physiological research / Academia Scientiarum Bohemoslovaca     Volume:  49     ISSN:  0862-8408     ISO Abbreviation:  Physiol Res     Publication Date:  2000  
Date Detail:
Created Date:  2001-01-17     Completed Date:  2001-03-22     Revised Date:  2008-04-02    
Medline Journal Info:
Nlm Unique ID:  9112413     Medline TA:  Physiol Res     Country:  Czech Republic    
Other Details:
Languages:  eng     Pagination:  567-75     Citation Subset:  IM    
Affiliation:
Department of Physiology, Second Faculty of Medicine, Charles University, Prague, Czech Republic. vaclav.hampl@lfmotol.cuni.cz
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MeSH Terms
Descriptor/Qualifier:
Angiotensin II / pharmacology*
Animals
Animals, Newborn / physiology*
Anoxia / physiopathology*
Blood Pressure / drug effects*
Blood Vessels / drug effects
Fetal Hypoxia / physiopathology*
Male
Nitroprusside / pharmacology
Pulmonary Circulation / drug effects*
Rats
Vasoconstrictor Agents / pharmacology*
Vasodilator Agents / pharmacology*
Chemical
Reg. No./Substance:
0/Vasoconstrictor Agents; 0/Vasodilator Agents; 11128-99-7/Angiotensin II; 15078-28-1/Nitroprusside

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


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