Affordable Access

24-hour rhythms in uterine and umbilical blood flows of conscious pregnant sheep.

Authors
  • Walker, A M
  • Oakes, G K
  • McLaughlin, M K
  • Ehrenkranz, R A
  • Alling, D W
  • Chez, R A
Type
Published Article
Journal
Gynecologic investigation
Publication Date
Jan 01, 1977
Volume
8
Issue
5-6
Pages
288–298
Identifiers
PMID: 25831
Source
Medline
License
Unknown

Abstract

The possibility that 24-hour rhythms exist in uterine blood flow (UtBF) and umbilical blood (UmBF) was investigated in 5 days postoperative chronically instrumented near-term pregnant sheep acclimated to a controlled environment. UtBF, UmBF and pressure measurements were made at 15-min intervals over 24 h beginning at 0800 h. Each data series was examined for the presence of significant rhythms of a 24-hour period using a method of Fourier analysis. UtBF 24-hour rhythms were found in all ewes; UmBF 24-hour rhythms were found in 4 of 5 lambs. A consistent reciprocal phase relationship between UtBF and UmBF was evident within animals. There were no associated rhythms in maternal arterial, fetal arterial, or amniotic fluid pressures. These results indicate that the presence of circadian rhythms must be considered as a possible variable when long-term uteroplacental hemodynamic studies are planned.

Report this publication

Statistics

Seen <100 times