Faculty Collaboration Database

Effect of age and blood pressure on the heart rate, vasopressin, and renin response to hypoxia in fetal sheep. Am J Physiol 1992 Oct;263(4 Pt 2):R880-4

Date

10/01/1992

Pubmed ID

1415801

DOI

10.1152/ajpregu.1992.263.4.R880

Scopus ID

2-s2.0-0026787621 (requires institutional sign-in at Scopus site)   18 Citations

Abstract

The purpose of these studies was to determine whether attenuating the increase in arterial and central venous pressure (CVP) during acute hypoxia can augment the renin and arginine vasopressin (AVP) responses to isocapnic hypoxia in chronically instrumented sheep fetuses. Young (122 +/- 2 days; n = 7) and old (133 +/- 1 days, n = 7) fetuses were exposed to hypoxemia (arterial PO2 = approximately 12-13 Torr) without and with attenuation of the increase in mean arterial pressure (MAP) and CVP with the simultaneous infusion of sodium nitroprusside (NP). NP did not attenuate the bradycardia induced by hypoxia. Plasma renin activity did not increase with hypoxia even when the potentially inhibitory effect of increased MAP and CVP was attenuated with NP. The AVP response to hypoxia was greater in the old fetuses. Furthermore, NP did augment the AVP response to hypoxia in the young but not old fetuses. We conclude that increases in MAP and CVP (i.e., baroreceptor input) do not influence the decrease in heart rate and lack of renin responses to acute hypoxia in the sheep fetus and that increased MAP and CVP seems to restrain the AVP response to hypoxia in younger sheep fetuses.

Author List

Raff H, Wood CE

Author

Hershel Raff PhD Professor in the Academic Affairs department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Arginine Vasopressin
Blood Pressure
Central Venous Pressure
Female
Fetal Blood
Fetal Diseases
Fetus
Gestational Age
Heart Rate, Fetal
Hypoxia
Pregnancy
Renin
Sheep