Amiloride inhibits arginine vasopressin-induced decrease in fetal lung liquid secretion.
The effects of arginine vasopressin (AVP) and amiloride were studied in 16 unanesthetized fetal sheep (129-135 days of age) with indwelling catheters. Secretion was measured by an impermeant tracer technique. Control fetuses showed no change in lung liquid secretion over a 5-h period with an average secretion rate of 3.6 +/- 0.31 ml.kg-1.h-1. Infusion of AVP (23.4 +/- 2.23 mU.kg-1.min-1) in seven fetuses (134-140 days of age) produced significant decreases (from control) in the secretion rate over a 5-h period: the secretion rate decreased by 68% in the last hour. Amiloride placed in the lung liquid during infusion of AVP, but after AVP effects had taken place, reversed the AVP-induced decrease in lung liquid secretion. AVP in conjunction with other hormones that are elevated during the stress of birth (epinephrine and cortisol) may be important in the removal of lung fluid at birth.
Cassin
S
S
Department of Physiology, College of Medicine, University of Florida, Gainesville 32610.
Perks
A M
AM
D000262:Adenylyl Cyclases / Q000378:metabolism; D000584:Amiloride / Q000494:pharmacology*; D000818:Animals; D001127:Arginine Vasopressin / Q000008:administration & dosage / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects; D000242:Cyclic AMP / Q000378:metabolism; D004837:Epinephrine / Q000502:physiology; D004848:Epithelium / Q000378:metabolism; D015633:Extravascular Lung Water / Q000378:metabolism*; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D008168:Lung / Q000187:drug effects / Q000196:embryology*; D011247:Pregnancy; D012711:Serum Albumin, Radio-Iodinated; D012756:Sheep; D015222:Sodium Channels / Q000378:metabolism
D012711:Serum Albumin, Radio-Iodinated; D015222:Sodium Channels; D001127:Arginine Vasopressin; D000584:Amiloride; D000242:Cyclic AMP; D000262:Adenylyl Cyclases; D004837:Epinephrine