Journal of Applied Physiology Fuel your research with LabChart
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

J Appl Physiol 70: 323-330, 1991;
8750-7587/91 $5.00
This Article
Right arrow Full Text (PDF)
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Gordon, J. B.
Right arrow Articles by Chu, K.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Gordon, J. B.
Right arrow Articles by Chu, K.

Journal of Applied Physiology, Vol 70, Issue 1 323-330, Copyright © 1991 by American Physiological Society

ARTICLES

Developmental changes in vascular responses to histamine in normoxic and hypoxic lamb lungs

J. B. Gordon, S. Clement de Clety and K. Chu
Department of Pediatrics, Montreal Children's Hospital, Quebec, Canada.

This study of newborn (3-10 day old) and juvenile (6-8 mo old) in situ isolated lamb lungs was undertaken to determine whether 1) histamine receptor blockade accentuates hypoxic pulmonary vasoconstriction more in newborns than in juveniles, 2) histamine infusion causes a decrease in both normoxic pulmonary vascular resistance and hypoxic pulmonary vasoconstriction in newborns, and 3) the H1-mediated dilator response to infused histamine in newborns is due to enhanced dilator prostaglandin release. Pulmonary arterial pressure (Ppa) was determined at baseline and in response to histamine (infusion rates of 0.1-10.0 micrograms.kg-1 min-1) in control, H1-blocked, H2-blocked, combined H1- and H2-blocked, and cyclooxygenase-inhibited H2-blocked lungs under "normoxic" (inspired O2 fraction 0.28) and hypoxic (inspired O2 fraction 0.04) conditions. In newborns, H1-receptor blockade markedly accentuated baseline hypoxic Ppa, and H2-receptor blockade caused an increase in baseline normoxic Ppa. In juveniles, neither H1 nor H2 blockade altered baseline normoxic or hypoxic Ppa. Histamine infusion caused both H1- and H2-mediated decreases in Ppa in normoxic and hypoxic newborn lungs. In juvenile lungs, histamine infusion also caused H2-mediated decreases in Ppa during both normoxia and hypoxia. During normoxia, histamine infusion caused an H1-mediated increase in normoxic Ppa in juveniles as previously seen in mature animals; however, during hypoxia there was an H1-mediated decrease in Ppa at low doses of histamine followed by an increase in Ppa. Combined histamine-receptor blockade markedly reduced both dilator and pressor responses to histamine infusion. Indomethacin failed to alter the H1-mediated dilator response to histamine in newborns.(ABSTRACT TRUNCATED AT 250 WORDS)


This article has been cited by other articles:


Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
V. Houfflin-Debarge, A. Delelis, S. Jaillard, B. Larrue, P. Deruelle, A. S. Ducloy, F. Puech, and L. Storme
Effects of nociceptive stimuli on the pulmonary circulation in the ovine fetus
Am J Physiol Regulatory Integrative Comp Physiol, February 1, 2005; 288(2): R547 - R553.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Lung Cell. Mol. Physiol.Home page
J. Belik, J. Pan, R. P. Jankov, and A. K. Tanswell
Bronchial epithelium-associated pulmonary arterial muscle relaxation in the rat is absent in the fetus and suppressed by postnatal hypoxia
Am J Physiol Lung Cell Mol Physiol, February 1, 2005; 288(2): L384 - L389.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online