Atrial natriuretic factor and sympathetic nervous output in response to volume shifts in the immature canine circulation.
This study evaluated the immature circulation's response to acute shifts in intravascular volume with respect to atrial natriuretic factor and plasma catecholamines. Serial measurements were performed on thirteen beagle puppies during volume expansion with a saline and albumin solution followed by volume contraction with furosemide. Atrial natriuretic factor correlated with right (r = .73, p less than 0.001) and left (r = .62, p less than 0.001) atrial pressures and increased to much greater levels than previously reported for mature animals. Simultaneously, 10 puppies had a progressive decrease in plasma norepinephrine over the 60-minute infusion (p less than 0.05) while two puppies demonstrated a marked increase between the 30- and 60-minute samples. Furosemide increased urine output and reversed the hormonal changes caused by volume expansion. Thus a greatly augmented output of atrial natriuretic factor occurs in the immature canine circulation in response to increased atrial and pulmonary pressures, while sympathetic output remains unchanged or falls with increasing intravascular volume until a critical decrease in cardiac output triggers a catecholamine surge.
Ross
R D
RD
Division of Pediatric Cardiology, Children's Hospital of Michigan Wayne State University School of Medicine, Detroit 48201.
Womack
S J
SJ
Gunther
S
S
Karpawich
P P
PP
Justice
C
C
Pinsky
W W
WW
D000375:Aging / Q000502:physiology; D000818:Animals; D009320:Atrial Natriuretic Factor / Q000502:physiology*; D002395:Catecholamines / Q000097:blood*; D004285:Dogs; D005665:Furosemide / Q000494:pharmacology; D006439:Hemodynamics / Q000187:drug effects / Q000502:physiology; D010953:Plasma Volume / Q000187:drug effects / Q000502:physiology*; D013564:Sympathetic Nervous System / Q000502:physiology*
D002395:Catecholamines; D005665:Furosemide; D009320:Atrial Natriuretic Factor