AJP - Endo Fuel your research with LabChart
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Am J Physiol Endocrinol Metab 263: E526-E533, 1992;
0193-1849/92 $5.00
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
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 Rosenfeld, C. R.
Right arrow Articles by Magness, R. R.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Rosenfeld, C. R.
Right arrow Articles by Magness, R. R.

AJP - Endocrinology and Metabolism, Vol 263, Issue 3 E526-E533, Copyright © 1992 by American Physiological Society

ARTICLES

Vasoconstrictor-induced secretion of ANP in fetal sheep

C. R. Rosenfeld, W. K. Samson, T. A. Roy, D. J. Faucher and R. R. Magness
Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas 75235.

Fetal secretion of atrial natriuretic peptide (ANP) increases during volume expansion and hypoxia. It is unknown whether this is associated with alterations in right atrial pressure (RAP) or distension and whether increases in ANP secretion reflect effects of specific vasopressors. To address this we studied fetal sheep (n = 13) at 125-140 days gestation, infusing either angiotensin II (ANG II; 0.023-5.73 micrograms/min) or the alpha-agonist phenylephrine (Phen; 0.031-7.64 micrograms/min) while monitoring mean arterial pressure (MAP), RAP, heart rate, and amniotic sac pressure. Arterial blood was obtained before and at 5 min of infusion to measure ANP, blood gases, and pH; umbilical venous blood was collected to determine placental clearance of ANP. ANG II caused dose-dependent increases in MAP and plasma ANP (P less than 0.05), whereas Phen caused dose-dependent increases in MAP, but ANP rose only with the highest dose (40 +/- 12%). delta MAP and delta RAP were highly correlated for Phen (r = 0.74, P = 0.002) and ANG II (r = 0.90, P less than 0.001), but for both agents the increase in delta RAP was proportionately greater than delta MAP, and increases in plasma ANP were greater per millimeter mercury rise in RAP than that observed with MAP. Increases in ANP were associated with a dose-dependent rise in hematocrit, suggesting decreases in intravascular volume. There was no fetal placental clearance of ANP. As in adults, ANG II- and alpha-agonist-induced fetal ANP secretion appears to primarily reflect increases in RAP and thus right atrial distension.


This article has been cited by other articles:


Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
H. Itoh, J. Zheng, I. M. Bird, K. Nakao, and R. R. Magness
Basic FGF decreases clearance receptor of natriuretic peptides in fetoplacental artery endothelium
Am J Physiol Regulatory Integrative Comp Physiol, August 1, 1999; 277(2): R541 - R547.
[Abstract] [Full Text] [PDF]


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