Acute alveolar hypoxia increases blood-to-tissue albumin transport:
role of atrial natriuretic peptide.
Albert, T. S. E., V. L. Tucker, and E. M. Renkin.
Department of Human Physiology, Davis, CA 95616
APStracts 3:0436A, 1996.
Plasma immunoreactive atrial natriuretic peptide (irANP) and blood-to
-tissue clearance of 131I-labeled rat serum albumin (CRSA) were
examined in anesthetized rats during hypoxic ventilation (n=5
-7/group). Hypoxia (10 min) increased irANP from 211+/-29 pg/ml (room
air) to 229+/-28 (15% O2, n.s.), 911+/-205 (10% O2), and 4374+/-961
(8% O2). Graded increases in CRSA were significant at 8% O2 in fat
(3.6-fold), ileum (2.2-fold), abdominal muscles (2.0-fold) kidney
(1.8-fold) and jejunum (1.4-fold). CRSA was decreased in back skin
and testes; heart, brain and lungs were unaffected. The increases in
CRSA were related to irANP and not PaO2. Circulating plasma volume
was negatively correlated with whole-body CRSA. Graded increases in
extravascular water content (EVW) were found in the kidney, left
heart and cerebrum; and were positively related to CRSA in the
kidney. EVW decreased in gastrointestinal tissues; the magnitude was
inversely related to CRSA. We conclude that ANP-induced protein
extravasation contributes to plasma volume contraction during acute
hypoxia.
Received 1 February 1996; accepted in final form September 1996.
APS Manuscript Number A115-6.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 7 October 1996