AJP - Regulatory, Integrative and Comparative Physiology, Vol 262, Issue 6 1117-R1120, Copyright © 1992 by American Physiological Society
Effects of intravenous saline infusion on fetal ovine lung liquid secretion
T. A. Davis, G. Gause, A. M. Perks and S. Cassin
Department of Physiology, College of Medicine, University of Florida, Gainesville 32610.
These studies were designed to investigate the relationship between body
fluid volume expansion and secretion of lung liquid in fetal sheep. Twelve
fetal animals were used for saline infusion studies after providing them
with indwelling vascular catheters and an exteriorized tracheal loop. An
additional 10 animals were used as controls. Lung liquid production was
measured using an impermeant tracer technique (Blue Dye Dextran). Saline
infusion at 1.6, 4.0, 15.6, and 19.2 ml.kg-1.h-1 did not alter
significantly lung liquid secretion rates. These results demonstrate that
1) intravenous infusion of saline at relatively high rates in the ovine
fetus does not affect net fetal lung liquid formation rate, and 2) the
lungs of chronically catheterized, unanesthetized fetal sheep probably do
not participate in regulation of excess fluid and electrolytes.
