Hypertension, Vol 9, 144-149, Copyright © 1987 by American Heart Association
R Garcia, M Cantin, J Gutkowska and G Thibault
Atrial natriuretic factor (ANF) was studied in rat plasma and atria 1, 2,
4, 6, and 8 weeks after constriction of the left renal artery and removal
of the contralateral kidney. Plasma ANF was elevated at all periods of
investigation. A positive correlation was observed between plasma ANF and
blood pressure (r = 0.56, p less than 0.001). The total atrial ANF content
(microgram/atrium) in one-kidney, one clip (1K1C) rats was lower during
Weeks 1 and 2, but only in the left atrium. Lower ANF concentrations
(microgram/mg protein) were also evident in the left atrium at Weeks 1, 2,
and 8, and in the right atrium at Week 8. A negative correlation between
ANF in plasma and in the left atrium was discerned (r = 0.43, p less than
0.01). Blood pressure (184 +/- 4 vs 114 +/- 4 mm Hg), body weight, and
plasma ANF were also examined in 1K1C rats and their normotensive controls
before and after unclipping. Blood pressure was normalized 6 hours after
unclipping. Plasma ANF declined in 1K1C rats within 6 hours after clip
removal, but it was still higher than in the controls. Plasma ANF was
similar in both groups on Days 9 and 13 after unclipping. There were no
differences in atrial ANF between hypertensive and normotensive animals 13
days after unclipping. The high levels of plasma ANF observed in 1K1C rats
probably are secondary to increased intra-atrial pressure caused by the
dual mechanism of expanded plasma volume and high blood pressure.
ARTICLES
Atrial natriuretic factor during development and reversal of one- kidney, one clip hypertension